"Even our encrypted military GPS receivers can be spoofed," Harrison says.
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Utilities and cellular networks also use GPs receivers for timing and controlling certain functions.
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The Zipline drones will use GPS receivers to navigate and communicate via the Rwandan cellular network.
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Besides their microprocessors, smartphones contain tiny versions of other components such as accelerometers, GPS receivers, radios and cameras.
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A key GPS vulnerability is the constant contact required between satellites in space and GPS receivers down on Earth.
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The authors also claimed that Ligado's plan would undermine first-responder helicopter operations and disrupt high-precision GPS receivers.
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Jaffe decided to deploy three to ideally five cylindrical moorings, which have GPS receivers and send out pings to the M-AUEs every 12 seconds.
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The bug, which some has described as the Y2K of GPS, will cause problems in some GPS receivers such as resetting the time and corrupting location data.
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A yacht's onboard network could have a vessel traffic service device, automatic identification system, autopilot, GPS receivers, radar, cameras, depth sounders, engine control and monitoring, and more.
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Geocaching is a global, multiplayer game that was born in 12017, when GPS technology became good enough for people to pinpoint specific locations with their GPS receivers.
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That should produce an effect that can be detected by GPS receivers as far away as South America — a prediction that will be tested during the upcoming eclipse.
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Bhatta is also planning to get reputed geological groups like the International Association of Geodesy on board, and Sherpas will be trained to plant GPS receivers atop Everest.
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For one, McKinlay notes, signals from these satellites are relatively faint, and can be bounced around by buildings or other structures, messing up the information gathered by GPS receivers.
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" And an official memorandum from the Department of Homeland Security says any GPS receivers running the latest IS-GPS-200 standard and connected to UTC "should not be adversely affected.
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A 2015 study using data from GPS receivers found that parts of south-central Iceland were rising by about 3.5 cm (1.4 inches) a year due to accelerated ice loss.
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All this is why some have compared the issue to a sort of mini Millennium, or, Y2K Bug for GPS receivers that will come into affect from April 6th this year. Bug.
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Uber CEO Travis Kalanick revealed that the company plans to soon add driverless cars—complete with "dozens of sensors that use cameras, lasers, radar, and GPS receivers"—to its fleet in Pittsburgh.
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Auto-steer systems, which use GPS receivers to keep rows straight and avoid gaps or overlap, are available for equipment ranging from tractors to harvest combines to sprayers with 100-foot-wide booms.
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In 2013 a team of researchers from the University of Texas at Austin successfully led astray an $80 million yacht in the Mediterranean, overpowering its GPS receivers and sending it onto a new course.
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Much like driving past a powerful radio station's antenna in your car and getting static on the radio, Ligado's high-power signals would bleed over and disrupt GPS receivers, sometimes within miles of their antennas.
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Read More: Space Wars Will Be Fought With Hacks, Not Missiles Since the US began developing its GPS satellite constellation in the late 70s, it has had two separate signal bands that were used by GPS receivers on the ground.
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If so, now is probably a good time to check whether or not those products are protected against the GPS Week Number Rollover issue — a sort of mini Y2K Bug for GPS receivers that will come into effect from April 6th this year.
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"As a combined software/hardware solution that includes atomic clocks and GPS receivers across Google's global network, Cloud Spanner also offers additional accuracy, reliability and performance in the form of a fully-managed cloud database service," Google claims in its blog post today.
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On a destroyer, the information flows into the Electronic Chart Display and Information System, which interfaces with the ship's GPS receivers and navigation sensors, such as speed and wind indicators, to give watchstanders a computerized real-time view of position and movement.
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Pulling in signals from one or more of these systems, along with a base station at a known position for reference, today's civilian GPS receivers can now pinpoint your location within 227 meters (it had been within an area about the size of a football field in the 2000s).
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The satellites, which are about the size of small suitcase and weigh about 64 pounds (30 kg) apiece, are basically GPS receivers that have been modified so they can not only detect radio waves coming from the spacecraft, but also the radio signals that bounce back off the surface of the ocean.
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DGPS would render it ineffective over the US, where it was considered most needed. Additionally, during the Gulf War of 1990-1991 SA had been temporarily turned off because Allied troops were using commercial GPS receivers. This showed that leaving SA turned off could be useful to the United States.GPS for Dummies, stating that there weren't enough military GPS receivers, so "Selective Availability was temporarily turned off in 1990 during the Persian Gulf War" so that Coalition troops could use civilian GPS receivers.
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Other specialized GPS devices offered by TeleType include GPS receivers, vehicle-mountable GPS trackers and other specialty items.
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This funding was used to add 15 Global Positioning System (GPS) receivers to the existing network of GPS receivers and radars of the Canadian High Arctic Ionospheric Network (CHAIN). The data will contribute significantly to the progress of space research by providing a better understanding of the processes in the Sun-Earth system.
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Manufacturers now integrate more advanced features, such as video recording, GPS receivers, data storage, and security mechanisms into the traditional cellphone.
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When using GPS receivers in street canyons with tall buildings, the shadowing and multipath effects may contribute to poor GPS signal reception.
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The company also produces proprietary road maps (DirectRoute), topographic maps (Topo), and marine charts (BlueNav) for use with its consumer GPS receivers.
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In Argentina, the brand was acquired by Gularo S.A., a manufacturer of MP3/MP4 players, DVDs, phones, GPS receivers, televisions and speakers.
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If the equipment exists, man overboard alerts are to be triggered on whatever electronic gear is available including GPS receivers and DSC radio transmitters.
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GVN 52, GVN 53 VIB 10 and VIB 11 were remotely mounted GPS receivers for integration with in-dash display units and car stereo systems.
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At midnight, the receivers with this firmware reported November 29, 2003 for one second and then reverted to November 28, 2003. Older Trimble GPS receivers had a software flaw that would insert a leap second immediately after the GPS constellation started broadcasting the next leap second insertion time (some months in advance of the actual leap second), rather than waiting for the next leap second to happen. This left the receiver's time off by a second in the interim. Older Datum Tymeserve 2100 GPS receivers and Symmetricom Tymeserve 2100 receivers also have a similar flaw to that of the older Trimble GPS receivers, with the time being off by one second.
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Asha series phones did not have GPS receivers; positioning was done by Cell ID of the cellular network or by using the Wi-Fi positioning system.
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Several GPS receivers are compatible with the RICOH Caplio 500SE. These devices deliver different accuracies, belong to various price levels and are available from different distributors.
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In the context of external land surveying, a base station is a GPS receiver at an accurately-known fixed location which is used to derive correction information for nearby portable GPS receivers. This correction data allows propagation and other effects to be corrected out of the position data obtained by the mobile stations, which gives greatly increased location precision and accuracy over the results obtained by uncorrected GPS receivers.
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Speech output is supported if Festival software is running. GpsDrive is designed to work with all Garmin GPS receivers having a serial port, as well as other GPS receivers with NMEA protocol support. GpsDrive is written in C, with use of the GTK+ graphical widget toolkit, and runs on Linux, FreeBSD and other Unix-like systems. It has interface support for different languages, such as English, German and French.
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Ham::Locator CPAN module Many commercially available general purpose (civil) Global Positioning System (GPS) receivers (e.g. Garmin GPS-12) have the option to display positions in Maidenhead Locator format.
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Post-processing is used in Differential GPS to obtain precise positions of unknown points by relating them to known points such as survey markers. The GPS measurements are usually stored in computer memory in the GPS receivers, and are subsequently transferred to a computer running the GPS post-processing software. The software computes baselines using simultaneous measurement data from two or more GPS receivers. The baselines represent a three-dimensional line drawn between the two points occupied by each pair of GPS antennas.
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Conventional GPS receivers integrate the received GPS signals for the same amount of time as the duration of a complete C/A code cycle which is 1 ms. This results in the ability to acquire and track signals down to around the −160 dBW level. High Sensitivity GPS receivers are able to integrate the incoming signals for up to 1,000 times longer than this and therefore acquire signals up to 1,000 times weaker, resulting in an integration gain of 30 dB.
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The interface to the User Segment (GPS receivers) is described in the Interface Control Documents (ICD). The format of civilian signals is described in the Interface Specification (IS) which is a subset of the ICD.
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GPS satellite clocks are synchronized to UTC (to within a published offset of a few seconds) as well as with each other. This enables GPS receivers to provide UTC time in addition to their position.
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As of 2005, AFSRs are still in research. AFSR techniques could make spread-spectrum receivers (such as GPS receivers and cell phones and Wi-Fi receivers and RFIDs) cost less and have longer battery lifetimes.
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External GPS-Receivers Non differential GPS devices have a significantly lower price than differential ones and deliver an accuracy of 2 to 10 m. They are used in car navigation devices and outdoor GPS receivers like the Garmin eTrex or the Fortuna Slim GPS. The precondition for any connection to the GPS device is that the GPS device is capable of sending NMEA data via Bluetooth and that it takes the slave role in the communication process with the camera. The camera will always take the master role.
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The United States National Spatial Reference System NAD 83(2011/MA11/PA11) epoch 2010.00, is a refinement of the NAD 83 datum using data from a network of very accurate GPS receivers at Continuously Operating Reference Stations (CORS).
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External GPS receivers are usually connected via Bluetooth. More and more mobile phones with integrated GPS are expected to come. Several other Location-based mobile games, such as BotFighters, are in the stage of research prototypes rather than being commercial successes.
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GPS technology enables individuals to observe relatively fine- scale movement or migratory patterns in a free-ranging wild animal using the Global Positioning System. After fitting animals with a GPS receiver, their position is determined by precisely timing the signals sent by GPS satellites high above the Earth, and the location of satellites sending the signals. As soon as GPS became available for civilian use in the 1990s, biologists started to attach GPS receivers to animals. Although the first civilian GPS receivers were developed by Magellan in 1989, they were very large and therefore impractical for animal applications.
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GPS receivers using two or more antennae mounted separately and blending the data with an inertial motion unit (IMU) can now achieve 0.02° in heading accuracy and have startup times in seconds rather than hours for gyrocompass systems. The devices accurately determine the positions (latitudes, longitudes and altitude) of the antennae on the Earth, from which the cardinal directions can be calculated. Manufactured primarily for maritime and aviation applications, they can also detect pitch and roll of ships. Small, portable GPS receivers with only a single antenna can also determine directions if they are being moved, even if only at walking pace.
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When selective availability was lifted in 2000, GPS had about a accuracy. The latest stage of accuracy enhancement uses the L5 band and is now fully deployed. GPS receivers released in 2018 that use the L5 band can have much higher accuracy, pinpointing to within .
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GPS receivers come in a variety of formats, from devices integrated into cars, phones, and watches, to dedicated devices such as these. The first portable GPS unit, Leica WM 101 displayed at the Irish National Science Museum at Maynooth. The user segment (US) is composed of hundreds of thousands of U.S. and allied military users of the secure GPS Precise Positioning Service, and tens of millions of civil, commercial and scientific users of the Standard Positioning Service (see GPS navigation devices). In general, GPS receivers are composed of an antenna, tuned to the frequencies transmitted by the satellites, receiver-processors, and a highly stable clock (often a crystal oscillator).
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RADARSAT-2 was constructed with several improvements over the RADARSAT-1 project, making it one of the most advanced radar imaging satellites in the world. Some of the improvements over RADARSAT-1 include increased spatial resolution, multiple polarization filters, solid state recorders, and GPS receivers on board.
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The design of distress beacons as a whole has evolved significantly since 1982. The newest 406-MHz beacons incorporate GPS receivers. Such beacons transmit in their distress message highly accurate position reports. The distress alert and location are forwarded almost instantly to SAR agencies via Cospas-Sarsat satellites.
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National Security." marines.mil, Retrieved: 1 November 2015. In 2005, work was completed on a series of upgrades to 11 of the Mexican Navy's Bo 105s, having received Forward looking infrared (FLIR) sensors, Global Positioning System (GPS) receivers, search radars, new rotor blades, armament pylons, and other changes."Procument, Mexico.
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The U.S. government controls the export of some civilian receivers. All GPS receivers capable of functioning above above sea level and , or designed or modified for use with unmanned missiles and aircraft, are classified as munitions (weapons)—which means they require State Department export licenses.Arms Control Association.Missile Technology Control Regime .
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Most modern PDAs have Bluetooth, a popular wireless protocol for mobile devices. Bluetooth can be used to connect keyboards, headsets, GPS receivers, and other nearby accessories. It's also possible to transfer files between PDAs that have Bluetooth. Many modern PDAs have Wi-Fi wireless network connectivity and can connect to Wi-Fi hotspots.
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Some PDAs include Global Positioning System (GPS) receivers; this is particularly true of smartphones. Other PDAs are compatible with external GPS-receiver add-ons that use the PDA's processor and screen to display location information. PDAs with GPS functionality can be used for automotive navigation. PDAs are increasingly being fitted as standard on new cars.
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To remove the effect of external, non-gravitational forces (e.g., drag, solar radiation pressure), the vehicles use sensitive Super STAR electrostatic accelerometers located near their respective centers of mass. GPS receivers are used to establish the precise positions of each satellite along the baseline between the satellites. The satellites use star cameras and magnetometers to establish attitude.
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Strategic Mapping was sold to Claritas in 1996, with the GIS mapping software being sold to ESRI. In 1995, Poizner founded SnapTrack, Inc., which pioneered technology that put GPS receivers into cell phones. Poizner served as its chief executive officer until he sold the privately held company to Qualcomm in 2000 for a reported $1.0 billion in Qualcomm stock.
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In 2003, Garmin launched the iQue line of integrated PDA-GPS receivers. On 31 October 2005, the iQue M4 became the first PDA that did not require a PC to preload the maps. The American version came with built-in maps of North America, while the UK version was supplied pre-loaded with maps of Western Europe.
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TeleType Co., Inc. is a privately held company in the United States, specialized in developing software for GPS devices. It was founded in 1981, under the name TeleTypesetting Company and it is based in Boston, Massachusetts. The company's product line includes automotive and commercial GPS navigation systems and other products including GPS receivers and tracking units.
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OpenStreetMap home page. OpenStreetMap (OSM), a citizen-led spatial data collection website, was founded by Steve Coast in 2004. Data are collected from diverse public domain sources; of which GPS tracks are the most important, collected by volunteers with GPS receivers. there were 340,522 registered OSM users, who had uploaded 2.121 billion GPS points onto the website.
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Fieldwork began in August 1998 and has continued since, though after about four years there was a funding cut-off as well as a deadline for book publication purposes late in 2002.Barrett et al., p.15. Methodology was based on that of the first Atlas but improved by the use of GPS receivers and scannable survey sheets.
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Lastly a cassette deck which was typically installed under the drivers seat with the digital maps used to interact with the system. This system worked very much like those of sailors before the existence of GPS receivers. The system required 3 tapes to cover the Northern California's Bay Area. Etak was sold to Rupert Murdoch in the 1980s.
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Kwangmyŏngsŏng- class satellites were launched from the former site by means of Paektusan and Unha rockets. So far, a total of three launch attempts were made, although none of them was successful.DPRK Satellite Missions, Globalsecurity.org, 10-22-2009 North Korea is also researching and deploying various military technologies, such as GPS jammers,North Korea Appears Capable of Jamming GPS Receivers, globalsecurity.
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Such a situation could be dangerous, as stopping distance increases with fewer functioning brakes. Dumping the brake line pressure from both the front and rear of the train simultaneously ensures that the entire train applies all of its brakes in emergency. Other electronics within the ETD were also enhanced, and many now include GPS receivers as well as the two-way radio communications.
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Generally, error in GPS elevation readings is specified to be 1.5 times the error in horizontal position readings. This means that the user of standard consumer GPS receivers should calculate for ±23 meters (75ft) of error with a Geometric DOP of 1. See: gpsinformation.net. This would account for the difference experienced by GPS users on the summit of Cima Tosa.
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Calculating the undulation is mathematically challenging. This is why many handheld GPS receivers have built-in undulation lookup tables to determine the height above sea level. The precise geoid solution by Vaníček and co-workers improved on the Stokesian approach to geoid computation. Their solution enables millimetre-to-centimetre accuracy in geoid computation, an order-of- magnitude improvement from previous classical solutions.
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Global Positioning System (GPS) receivers can also determine altitude by trilateration with four or more satellites. In aircraft, altitude determined using autonomous GPS is not reliable enough to supersede the pressure altimeter without using some method of augmentation. In hiking and climbing, it is common to find that the altitude measured by GPS is off by as much as depending on satellite orientation.
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Improvements in electronics allowed GPS receivers to effectively take several fixes at once, greatly reducing the complexity of deducing a position. GPS uses many more satellites than were used with Transit, allowing the system to be used continuously, while Transit provided a fix only every hour or more. After 1996, the satellites were kept in use for the Navy Ionospheric Monitoring System (NIMS).
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The Ricoh 500SE digital compact camera is suitable for outdoor photography and networkability. Capability includes external information such as GPS position or barcode numbers within the image headers. External vendors sell hardware and software for workflows involving GPS positioning or barcode scanning. Most NMEA compliant bluetooth GPS receivers can be used with this camera through its built in bluetooth communication capability.
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Professional External GPS-Receivers Professional, differential GPS devices come from the surveying sector and are significantly more expensive than non- differential ones. Due to additional correction signals they can reach accuracies in the range of centimeters. The same Bluetooth preconditions apply as with non differential receivers. The mobile, Bluetooth enabled GPS device MobileMapper CE from Thales provides submeter GPS positions.
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In the United States, GPS receivers are regulated under the Federal Communications Commission's (FCC) Part 15 rules. As indicated in the manuals of GPS-enabled devices sold in the United States, as a Part 15 device, it "must accept any interference received, including interference that may cause undesired operation." With respect to GPS devices in particular, the FCC states that GPS receiver manufacturers, "must use receivers that reasonably discriminate against reception of signals outside their allocated spectrum." For the last 30 years, GPS receivers have operated next to the Mobile Satellite Service band, and have discriminated against reception of mobile satellite services, such as Inmarsat, without any issue. The spectrum allocated for GPS L1 use by the FCC is 1559 to 1610 MHz, while the spectrum allocated for satellite-to-ground use owned by Lightsquared is the Mobile Satellite Service band.
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OEM GPS receiver module measuring GPS receivers may include an input for differential corrections, using the RTCM SC-104 format. This is typically in the form of an RS-232 port at 4,800 bit/s speed. Data is actually sent at a much lower rate, which limits the accuracy of the signal sent using RTCM. Receivers with internal DGPS receivers can outperform those using external RTCM data.
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Geotagging is gaining popularity with photographers to produce geotagged photographs. A few cameras have built- in geolocation capability. Most, apart from smartphones, do not, so many photographers rely on external GPS receivers to determine location. Location may be inserted immediately into the picture file by tethering with Bluetooth or suitable wired connection, which are about as rare in cameras as the built- in autogeotagging feature.
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Namsung (; ) is a South Korean multinational company headquartered in Seoul. Namsung was founded by Yoon Bong-Soo in 1965 as an OEM electronics manufacturing company. Namsung's subsidiaries include Namsung Telecom, Dreamer, Namsung International, and Namsung America. Namsung America ( Dual Electronics Corp) produces and sells a wide selection of mobile electronics, marine electronics, home audio, and GPS receivers under the Dual, Axxera, and Jensen brands.
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Newer Nextel radios have embedded GPS receivers which are polled if 9-1-1 is dialed. The 9-1-1 center is provided with latitude and longitude from the radio's GPS receiver. In centers with computer-aided dispatch, the system may assign an address to the call based on these coordinates or may project an icon depicting the caller's location onto a map of the area.
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Aebi did not have a GPS receiver because civilian GPS receivers were unavailable. Instead, Aebi had a sextant for celestial navigation and a radio direction finder. She used the first leg of her trip from New Jersey to Bermuda as a sea trial of her boat and was plagued by factory defects that might easily have been corrected before departure had they been exposed.
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Many mobile devices feature a dock connector. Dock connectors can be used to interface with accessories such as external speakers, including stereo systems and clock radios. Automotive accessories for mobile devices include charging cradles, FM transmitters for playing audio through the car's speakers, and GPS receivers. There are dock connector cables that offer additional capabilities such as direct integration with the car's audio system and controls.
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In parallel to the actual voice call, the ALI database gets periodically updated with more precise and recent location information. Cellular networks can determine a more precise location of the caller's device by using triangulation from the cell towers (radiolocation). In addition to triangulation, a second source of location information may be the caller's phone itself (or other cellular device). Many phones manufactured after 2005 have GPS receivers built in.
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Artist's conception of GPS Block II-F satellite in Earth orbit. Civilian GPS receiver ("GPS navigation device") in a marine application. Global Positioning System (GPS) satellites broadcast microwave signals to enable GPS receivers on or near the Earth's surface to determine location and time, and to derive velocity. The system is operated by the U.S. Department of Defense (DoD) for use by both the military and the general public.
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Geodashing is an outdoor sport in which teams of players use GPS receivers to find and visit randomly selected "dashpoints" (also called "waypoints") around the world and report what they find. The objective is to visit as many dashpoints as possible. Unlike geocaching, nothing is to be left at the dashpoints; the sole objective is to visit them within the time limit. The first game, organized by gpsgames.
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IRIG timecodes are standard formats for transferring timing information. Atomic frequency standards and GPS receivers designed for precision timing are often equipped with an IRIG output. The standards were created by the Telecommunications Working Group of the United States military's Inter-Range Instrumentation Group (IRIG), the standards body of the Range Commanders Council. Work on these standards started in October 1956, and the original standards were accepted in 1960.
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The GPS position and attitude determination system was designed and built by student researchers at The University of Texas' GPS Research Lab. The system utilizes GPS code measurements, as well as antenna signal-to-noise ratio (SNR) and 3-axis magnetometer measurements to provide estimates of position, velocity, and attitude. Each satellite will have redundant ORION GPS receivers, dual cross-strapped antennas with RF switching and splitting hardware.
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The GAGE Facility provides geodetic support to NSF-OPP (National Science Foundation Office of Polar Programs) funded researchers working in the Arctic and Antarctic. Survey-grade GPS receivers, Terrestrial Laser Scanners, and supporting power and communications systems for continuous data collection and campaign surveying are available. Operation and maintenance services are also provided for long term data collection, with on-line data distribution from the UNAVCO community archive.
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The goal is to provide models of time- dependent strain associated with a number of recent earthquakes and other geologic events as constrained by GPS data. With the use of InSAR (Interferometric Synthetic Aperture Radar), a remote-sensing technique, and PBO (Plate Boundary Observatory), a fixed array of GPS receivers and strainmeters, the EarthScope project will provide spatially continuous strain measurements over wide geographic areas with decimeter to centimeter resolution.
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While internal hardware varies, most have an electronic visual display, either backlit LCD or OLED. Some use transflective or electronic paper, to consume less power. They are generally powered by a rechargeable lithium-ion battery. Peripheral devices may include digital cameras, thermometers, accelerometers, pedometers, heart rate monitors, altimeters, barometers, compasses, GPS receivers, tiny speakers, and microSD cards, which are recognized as storage devices by many other kinds of computers.
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Since the advent of GPS, highly precise, yet affordable timing is available from many commercial GPS receivers. Its initial system design expected general timing precision better than 340 nanoseconds using low-grade "coarse mode" and 200 ns in precision mode. A GPS receiver functions by precisely measuring the transit time of signals received from several satellites. These distances combined geometrically with precise orbital information identify the location of the receiver.
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Integrated Multifunction Sight Device Night Vision Equipment, Thermal Imager, a Laser Range-Finder, Colour Charge-Coupled-Device (CCD) Camera, an Indian Regional Navigation Satellite System (IRNSS) device and a Digital Magnetic Compass, Compact Laser-Based Instruments, Integrated Electro-Optical Surveillance and Fire Control Systems, Advanced IRNSS/GPS receivers, Infrared sensors, Thermal sensors, Electro optical sensors, Spectroscopic sensors, Electromagnetic and Radio frequency sensors and many other sensors, radars and jammers would also be carried.
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This allows one display unit to show many different types of information. It also allows the instruments to work together, since they share data. NMEA 2000 is meant to be "plug and play" to allow devices made by different manufacturers to communicate with each other. Examples of marine electronics devices to include in a network are GPS receivers, auto pilots, wind instruments, depth sounders, navigation instruments, engine instruments, and nautical chart plotters.
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The Trinetra project aims to develop cost- effective, independence-enhancing technologies to benefit blind people. One such system addresses accessibility concerns of blind people using public transportation systems. Using GPS receivers and staggered Infrared sensors, information is relayed to a centralized fleet management server via a cellular modem. Blind people, using common text-to-speech enabled cell phones can query estimated time of arrival, locality, and current bus capacity using a web browser.
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GPS units, internal or external, require a lock from at least three satellites (for position), which usually requires up to 60 seconds. However, acquisition time is decreasing rapidly with hardware improvements. Some 21st-century GPS receivers use cell tower location and one global positioning satellite to obtain a faster lock on location. This technology known as assisted GPS (aGPS) is becoming more popular in cellular phones, since it leverages cell tower locations.
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At the same time, it began offering downloadable satellite and USGS 7.5-minute quads that could be overlaid on its maps using a new NetLink feature. Earlier models of Earthmate were among the first GPS receivers tethered to laptops. In 2006/2007, the firm introduced its first full-featured GPS standalone receiver, the Earthmate GPS PN-20. During 2008, the company continued expanding its handheld GPS line with the Earthmate GPS PN-40 model.
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Samsung Galaxy Note phablets include a stylus, called "S-Pen". Pen computing refers to any computer user-interface using a pen or stylus and tablet, over input devices such as a keyboard or a mouse. Pen computing is also used to refer to the usage of mobile devices such as tablet computers, PDAs and GPS receivers. The term has been used to refer to the usage of any product allowing for mobile communication.
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On ships and aircraft, GPS receivers are often equipped with two or more antennas, separately attached to the vehicle. The exact latitudes and longitudes of the antennas are determined, which allows the cardinal directions to be calculated relative to the structure of the vehicle. Within these limitations GPSRs are considered both accurate and reliable. The GPSR has thus become the fastest and most convenient way to obtain a verifiable alignment with the cardinal directions.
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GPS-IR was used in the Earthscope Plate Boundary Observatory. Larson also showed that it is possible to measure sea level changes, which allows the monitoring of subsidence and ground motion caused by earthquakes. These GPS receivers act as tide gauges, and can be tied to a terrestrial reference frame. She used them to monitor tidal levels in Kachemak Bay, and found that GPS was in good agreement with records from traditional tide gauges.
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DRAGONSat is planned to be an eight-year program with a launch of the satellites approximately every two years. The first three missions will test individual components and subsystems while the final mission will culminate with the successful docking of two satellites. Each mission builds upon the previous mission culminating in a fully autonomous rendezvous and docking mission. Both universities are required to use GPS receivers designed by NASA in order to determine its functionality.
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A number of organizations reported problems caused by flawed software following the June 30, 2012, leap second. Among the sites which reported problems were Reddit (Apache Cassandra), Mozilla (Hadoop), Qantas, and various sites running Linux. Older versions of Motorola Oncore VP, UT, GT, and M12 GPS receivers had a software bug that would cause a single timestamp to be off by a day if no leap second was scheduled for 256 weeks. On November 28, 2003, this happened.
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Although four satellites are required for normal operation, fewer apply in special cases. If one variable is already known, a receiver can determine its position using only three satellites. For example, a ship or aircraft may have known elevation. Some GPS receivers may use additional clues or assumptions such as reusing the last known altitude, dead reckoning, inertial navigation, or including information from the vehicle computer, to give a (possibly degraded) position when fewer than four satellites are visible.
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Another milestone in orbit determination was Carl Friedrich Gauss' assistance in the "recovery" of the dwarf planet Ceres in 1801. Gauss's method was able to use just three observations (in the form of celestial coordinates) to find the six orbital elements that completely describe an orbit. The theory of orbit determination has subsequently been developed to the point where today it is applied in GPS receivers as well as the tracking and cataloguing of newly observed minor planets.
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Wingsuit pilots often use tools including portable GPS receivers to record their flight path. This data can be analyzed later to evaluate flight performance in terms of fall rate, speed, and glide ratio. When jumping for the first time at a new location, BASE jumpers will often evaluate terrain using maps and laser range finders. By comparing a known terrain profile with previously recorded flight data, jumpers can objectively evaluate whether a particular jump is possible.
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Newest designs incorporate GPS receivers to transmit highly accurate positions (within about 20 metres) of the distress position. The original COSPAS/SARSAT satellites could calculate EPIRB position to within about by using Doppler techniques. By the end of 2010 EPIRB manufacturers may be offering AIS (automatic identification system) enabled beacons. The serviceability of these items is checked monthly and annually and they have limited battery shelf life, between two and five years using mostly lithium-type batteries.
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CHAIN site in Sanikiluaq, Nunavut The Canadian High Arctic Ionospheric Network (CHAIN) is an array of ground-based radio instruments deployed in the Canadian Arctic and operated by the University of New Brunswick. The CHAIN instruments include high data-rate GPS receivers and digital ionosondes. After passing through the Earth's ionosphere, microwave GPS signals carry information about the total electron content (TEC). This information is commonly used to improve the precision of GPS and to study ionospheric morphology.
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Inter-range instrumentation group timecodes, commonly known as IRIG timecode, are standard formats for transferring timing information. Atomic frequency standards and GPS receivers designed for precision timing are often equipped with an IRIG output. The standards were created by the Tele Communications Working Group of the U.S. military's Inter-Range Instrumentation Group (IRIG), the standards body of the Range Commanders Council. Work on these standards started in October 1956, and the original standards were accepted in 1960.
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Some cameras, GPS receivers and PDAs detect the safe end-of-discharge voltage of the series cells and perform an auto-shutdown, but devices such as flashlights and some toys do not. Irreversible damage from polarity reversal is a particular danger, even when a low voltage-threshold cutout is employed, when the cells vary in temperature. This is because capacity significantly declines as the cells are cooled. This results in a lower voltage under load of the colder cells.
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Its invention was described as having had "a profound effect on modern digital communications". The primary application of Costas loops is in wireless receivers. Its advantage over other PLL-based detectors is that at small deviations the Costas loop error voltage is \sin(2(\theta_i-\theta_f)) as compared to \sin(\theta_i-\theta_f). This translates to double the sensitivity and also makes the Costas loop uniquely suited for tracking Doppler-shifted carriers especially in OFDM and GPS receivers.
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Similar paid or free apps are also available for all device platforms. Similar applications are available for computers. Computers rarely have built-in GPS receivers or mobile telephone network connectivity, so these methods of location and signalling are not available. A computer connected to the Internet by a cabled connection gives its location as the location of the Internet Service Provider (ISP) it is connected to, usually a long distance away and not very useful, although the IP address may help.
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Many kayak anglers have started customizing their kayaks for fishing. These manufacturers offer special models for fishing that are designed and accessorized for this sport, including specially designed hatches, built-in coolers & rod holders, gps receivers and equipment mounts. Other accessories include live wells, anchor trolleys and running lights. Specially designed fishing kayaks usually have designs similar to those of recreational sit-in and sit-on-top kayaks characterized by very wide beams (up to 36 inches) that increase lateral stability.
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The relative accuracy is likewise improved, to about 2.5 cm. Even if the StarFire correction signal is lost for more than 20 minutes, the internal ionospheric corrections alone result in accuracy of about 3 m. StarFire receivers also receive WAAS signals, ignoring their ionospheric data and using their (less detailed) ephemeris and clock adjustment data to provide about 50 cm accuracy. In comparison, "normal" GPS receivers generally offer about 15 m accuracy, and ones using WAAS improve this to about 3 m.
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The availability of relatively inexpensive batteries, displays and GPS receivers, enabled by the smartphone supply chains, provided easily accessible components to facilitate dockless services worldwide. Outside of Chinese cities, non-electric dockless bikeshare has largely disappeared, with many companies switching from bicycles to electric kick scooters in 2019. E-scooters, a form of micromobility, are popular in cities for short trips. Shared electric kick scooters are considered to have one of the most rapid adoption rates in transport, nearly 4% in one year.
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Fully automatic systems allow the ability of the machine's implements to be controlled by the GPS guidance system. This is typically used in the fine grading applications where precise levels of material need to be moved on a predetermined design or grade. The advantages to this system is due to the accuracy that can be achieved with GPS and RTK, but requires an onsite base station. These systems can use either one or two GPS receivers and are mounted on the machine's blade.
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Gunston and Gilchrist 1993, p. 211. Instead, a life-extension program involving the re- winging of existing A-6E aircraft was undertaken; initially a metal wing had been used before a graphite-epoxy composite wing was developed during the late 1980s.Gunston and Gilchrist 1993, p. 211-212. Other improvements were introduced to the fleet around this time, including GPS receivers, new computers and radar sets, more efficient J-52-409 engines, as well as increased compatibility with various additional missiles.
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Manufactured by Rockwell Collins, the DAGR entered production in March 2004, with the 40,000th unit delivered in September 2005. It was estimated by the news source Defense Industry Daily that, by the end of 2006, the USA and various allies around the world had issued almost $300 million worth of DAGR contracts, and ordered almost 125,000 units.$82.7M more for DAGR GPS Receivers. Defense Industry Daily The DAGR replaced the Precision Lightweight GPS Receiver (PLGR), which was first fielded in 1994.
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The use of yield sensors developed from new technologies, combined with the advent of GPS receivers, has been gaining ground ever since. Today, such systems cover several million hectares. In the American Midwest (US), it is associated not with sustainable agriculture but with mainstream farmers who are trying to maximize profits by spending money only in areas that require fertilizer. This practice allows the farmer to vary the rate of fertilizer across the field according to the need identified by GPS guided Grid or Zone Sampling.
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Septentrio is also known to first introduce single-board attitude determination systems based on the multi-antenna version of its GPS receivers. Septentrio’s receivers were used to track experimental Galileo signals transmitted by the GIOVE-A satellite and were also the first to track the signals of the first experimental satellite of the future Chinese Compass navigation system. In the line of user products the company keeps its focus on multi-system receivers that make use of all the navigation signals available in the sky.
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Significant changes were made both during and shortly after the war. Owing to obsolete navigational systems being unable to provide the accuracy required, both French and British Jaguars were quickly modified with Global Positioning System (GPS) receivers, a recent technology at the time.Russell and Hasik 2002, p. 151. Prior to 1995 NATO bombing campaign in Bosnia and Herzegovina known as Operation Deliberate Force, a dozen Jaguars were upgraded with the capability to carry the TIALD laser designator pod and redesignated Jaguar GR1B or T2B respectively.
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The company's initial product was stolen vehicle location and corporate fleet vehicle location, using a technique called multilateration. Specialized base stations and receivers were installed throughout a city, and vehicles equipped with special transmitters could have their location determined on command. Once GPS receivers became affordable, Teletrac discontinued its network-based positioning system and began marketing products and services centered around a cloud-based GPS tracking platform. It has been used for numerous purposes over the years including tracking stolen vehicles and monitoring fuel consumption.
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There are three EarthScope observatories, these include the San Andreas Fault Observatory at Depth (SAFOD), the Plate Boundary Observatory (PBO), and the Seismic and Magnetotelluric Observatory (USArray). These observatories consist of boreholes into an active fault zone, global positioning system (GPS) receivers, tiltmeters, long-baseline laser strainmeters, borehole strainmeters, permanent and portable seismographs, and magnetotelluric stations. The various EarthScope components will provide integrated and highly accessible data on geochronology and thermochronology, petrology and geochemistry, structure and tectonics, surficial processes and geomorphology, geodynamic modeling, rock physics, and hydrogeology.
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This approximately wooded site located on the south side of the campus was designated an official Schoolyard Habitat in 2006 by the National Wildlife Federation. Ecology students help collect animal and plant data annually using a variety of tools and technologies including Global Positioning Satellite (GPS) receivers and digital cameras. They also construct nesting boxes for birds and roosting boxes for bats to help increase the biodiversity of the area. Many other classes use the area as an outdoor classroom, including art, English, performing arts, and technology.
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Near the end of the 20th century, the advent of satellite-based Global Positioning Systems (GPS) provided yet another means for any individual to determine true north accurately. While GPS Receivers (GPSRs) function best with a clear view of the entire sky, they function day or night, and in all but the most severe weather. The government agencies responsible for the satellites continuously monitor and adjust them to maintain their accurate alignment with the Earth. There are consumer versions of the receivers that are attractively priced.
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This audio signal allows the pilot to concentrate on the external view instead of having to watch the instruments, thus improving safety and also giving the pilot more opportunity to search for promising looking clouds and other signs of lift. A variometer that produces this type of audible tone is known as an "audio variometer". Advanced electronic variometers in gliders can present other information to the pilot from GPS receivers. The display can thus show the bearing, distance and height required to reach an objective.
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The trail is open primarily to hiking, although other activities are allowed where the trail follows other existing routes. Although the trail is divided into shorter segments, there are numerous opportunities for longer- distance backpacking trips, with camping opportunities including shelters in both units of the Kettle Moraine State Forest. Several trail chapters offer awards for completing all segments within their jurisdiction, and the Alliance also has a "cold cache" program to encourage hikers to seek out glacial features along the trail using GPS receivers.
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Global-Inertial Positioning Systems Image Capture for Asset Management (GIPSICAM) is a mobile-mapping system used internally by the Roads & Maritime Services to survey New South Wales state roads. The main components of the system include multiple redundant GPS receivers, INS (a part of the GIPSITRAC module), data acquisition computers and cameras mounted inside a cupola on the vehicle roof. The conventional instrument configuration is supported by comprehensive data processing algorithms and advanced geo-referencing techniques optimized for independent positioning and road geometry modelling.
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The application supports many types of GPS receivers with connections via serial ports, USB, and Bluetooth. Starting in 2009, gpsd also supports AIS receivers.A Brief History of GPSD, "In July and August 2009 ESR redesigned the GPSD command protocol and gave gpsd the ability to read data from marine AIS receivers and pass it to clients."; retrieved 2011-05-01 gpsd supports interfacing with the Network Time Protocol (NTP) server ntpd via shared memory to enable setting the host platform's time via the GPS clock.
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Those Pumas that had been assigned to the role of performing combat search- and-rescue duties were quickly retrofitted with GPS receivers to enhance their navigational capabilities.Rip and Hasik 2002, p. 155 As part of France's contribution to the 1990s NATO-led intervention in the Yugoslav Wars, a number of French Pumas operated in the region alongside other Puma operators such as Britain and the United Arab Emirates; one frequent mission for the type was the vital provision of humanitarian aid missions to refugees escaping ongoing ethnic genocide.
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The $13.4 million system is funded by MassDOT; it uses existing Automatic Vehicle Identification (AVI) systems plus additional sensors in the tunnels, and GPS receivers on the surface sections. In September 2013, the MBTA announced that "Next Train" signs would be unveiled at Kenmore that month. On October 23, 2014, location tracking data became available for Green Line trains above ground. Arrival predictions for surface stations – including the activation of countdown signs along the D branch – and underground tracking and predictions were to be rolled out in two phases by early 2015.
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Track circuit indications are available digitally in signal houses at the Park Street interlocking, at the new North Station interlocking, and at the new Kenmore interlocking, but are not transmitted to OCC. In January 2013, the MBTA announced plans to add full vehicle location tracking on the Green Line for countdown signs and smartphone applications, including using AVI data in the tunnels and GPS receivers on the surface lines. The first real-time data—location data on the surface lines—became available in October 2014. Full tracking was expected by early 2015.
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GPS receivers have clocks as well, but they are less stable and less precise. Each GPS satellite continuously transmits a radio signal containing the current time and data about its position. Since the speed of radio waves is constant and independent of the satellite speed, the time delay between when the satellite transmits a signal and the receiver receives it is proportional to the distance from the satellite to the receiver. A GPS receiver monitors multiple satellites and solves equations to determine the precise position of the receiver and its deviation from true time.
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Modern goods wagons are authorised for speeds up to around and in certain countries, wagons are increasingly equipped with GPS receivers and transponders which provide location monitoring as required. The Deutsche Bahn (DB) even has goods wagons cleared for high-speed rail travel at up to . Because the braking distance of fast goods trains is longer than the separation between distant and home signals (as are Express Passenger trains), they may only run at high speeds of with locos on routes with early signalling systems in the driver's cab (LZB, FZB and ETCS).
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The low price and ubiquity of Global Positioning System or GPS equipment has lent itself to more accurate and reliable telelocation systems. GPS signals are impervious to most electrical noise sources and don't require the user to install an entire system. Usually only a receiver to collect signals from the satellite segment is installed in each vehicle and radio or GSM to communicate the collected location data with a dispatch point. Large private telelocation or AVL systems send data from GPS receivers in vehicles to a dispatch center over their private, user-owned radio backbone.
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Historically, Damascus International Airport was a major stopover point for Hezbollah fighters on their way to more advanced training in Iran. Hezbollah obtains some weaponry from black markets and possibly from the Lebanese military. Dual-use technology, including night vision goggles, laser rangefinders, GPS receivers, advanced aircraft-analysis and design software, stun guns, nitrogen laser cutters, naval equipment, and ultrasonic dog deterrents were purchased from private vendors in the United States and Canada in the early 2000s. Hezbollah is able to fight at night and has advanced night vision technology.
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The European Union's Galileo positioning system is a next generation GNSS in the final deployment phase, and became operational in 2016. China has indicated it may expand its regional Beidou navigation system into a global system. More than two dozen GPS satellites are in medium Earth orbit, transmitting signals allowing GPS receivers to determine the receiver's location, speed and direction. Since the first experimental satellite was launched in 1978, GPS has become an indispensable aid to navigation around the world, and an important tool for map-making and land surveying.
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Lowrance is a manufacturer of consumer sonar and GPS receivers, as well as digital mapping systems. Headquartered in Tulsa, Oklahoma, with production facilities in Ensenada, Mexico, Lowrance employs approximately 1,000 people. The company is best known for its High Definition Systems (HDS) and add-on performance modules which include Broadband 4G Radar, StructureScan with SideScan and DownScan Imaging, Sonic Hub Audio, Sirius LWX-1 Weather, and NAIS Collision Avoidance. In 2006, Simrad Yachting and Lowrance merged in a deal valued at $215 million, creating a new company named Navico.
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GPS is based on a network of satellites that constantly transmit radio signals. GPS receivers pick up these transmissions and compare the signals from several satellites in order to pinpoint the receiver's location to within a few meters. This is done by comparing the time at which the signal was sent from the satellite to when it was picked up by the receiver. Because the orbital paths of the satellites are known very accurately, the receiver can perform a calculation based on its distance to several of the orbiting satellites and therefore obtain its position.
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Larson has also worked on hydrogeodesy, as well as advising the US Federal Government on geodetic infrastructure. Larson noticed that there were errors caused by the interference of GPS signals, which correlated with the water content in the surfaces close to the receiving antenna. She showed that geodetic GPS receivers can be used to detect the water content of soil, as well as the depth of snow, snow water equivalent, and vegetation water content. She first demonstrated this capability in 2012, when she transformed a GPS network to be capable of interferometric reflectometry (GPS IR).
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Near-Earth Asteroid Scout concept: a controllable solar sail CubeSat Attitude control (orientation) for CubeSats relies on miniaturizing technology without significant performance degradation. Tumbling typically occurs as soon as a CubeSat is deployed, due to asymmetric deployment forces and bumping with other CubeSats. Some CubeSats operate normally while tumbling, but those that require pointing in a certain direction or cannot operate safely while spinning, must be detumbled. Systems that perform attitude determination and control include reaction wheels, magnetorquers, thrusters, star trackers, Sun sensors, Earth sensors, angular rate sensors, and GPS receivers and antennas.
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The location he recorded, , accurately matches the location given by Russian topographic mapping and SRTM data, although these sources show its height to be slightly lower, at 1,052 meters. However, SRTM data has been demonstrated to have about 5-9m vertical accuracy, while most tracking grade handheld GPS receivers also have several meters of vertical inaccuracy. Only accurate DGPS or RTK-GPS survey, or airborne LIDAR/photogrammetric survey can yield more accurate result. Recently two trekking clubs counted the height of "Saka Haphong" as 3,488 and 3,461 feet, respectively.
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Precise timing is fundamental to an accurate GPS location. The time from an atomic clock onboard each satellite is encoded into the radio signal; the receiver determines how much later it received the signal than it was sent. To do this, a local clock is corrected to the GPS atomic clock time by solving for three dimensions and time based on four or more satellite signals. Improvements in algorithms lead many modern low-cost GPS receivers to achieve better than 10-meter accuracy, which implies a timing accuracy of about 30 ns.
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The resulting aircraft bears little resemblance to the original TG-8. Installation of the twin-boom pods permits the carriage of more sensors. The left-hand pod houses an AN/APN-215(V) color multi-function X-band sea search radar with mapping capabilities. The right-hand pod houses the AN/AAQ-15 forward looking infrared (FLIR) and Low-Light TV enhanced vision systems. For navigation the RU-38A originally carried both OMEGA and GPS receivers, although the Omega has since been removed with that system's withdrawal from service in 1997.
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A good High Sensitivity GPS receiver can acquire signals down to −185 dBW, and tracking can be continued down to levels approaching −190 dBW. High Sensitivity GPS can provide positioning in many but not all indoor locations. Signals are either heavily attenuated by the building materials or reflected as in multipath. Given that High Sensitivity GPS receivers may be up to 30 dB more sensitive, this is sufficient to track through 3 layers of dry bricks, or up to 20 cm (8 inches) of steel-reinforced concrete for example.
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User privacy may be compromised if GPS receivers in handheld devices such as mobile phones upload user geo-location data through associated software installed on the device. User geo-location is currently the basis for navigational apps such as Google Maps, location-based advertising, which can promote nearby shops and may allow an advertising agency to track user movements and habits for future use. Regulatory bodies differ between countries regarding the treatment of geo- location data as privileged or not. Privileged data cannot be stored, or otherwise used, without the user's consent.
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MCX and the smaller MMCX connector are frequently used to connect external antennas to GPS receivers. They are also common on USB DVB-T tuners for computers and laptops, to connect an external antenna to the tuner. The MCX connector is also being used on at least some of the new generation of mostly inexpensive software-defined oscilloscopes and/or signal generators such as the DS212. This is a low frequency application, at most a few MHz bandwidth, so the electrical performance characteristics are relatively unimportant, however the small size would appear to be an important feature.
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This suggested that broadcasting this offset to local GPS receivers could eliminate the effects of SA, resulting in measurements closer to GPS's theoretical performance, around 15 meters. Additionally, another major source of errors in a GPS fix is due to transmission delays in the ionosphere, which could also be measured and corrected for in the broadcast. This offered an improvement to about 5 meters accuracy, more than enough for most civilian needs. The US Coast Guard was one of the more aggressive proponents of the DGPS, experimenting with the system on an ever-wider basis through the late 1980s and early 1990s.
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The clocks at CERN and LNGS had to be in sync, and for this the researchers used high-quality GPS receivers, backed up with atomic clocks, at both places. This system timestamped both the proton pulse and the detected neutrinos to a claimed accuracy of 2.3 nanoseconds. But the timestamp could not be read like a clock. At CERN, the GPS signal came only to a receiver at a central control room, and had to be routed with cables and electronics to the computer in the neutrino-beam control room which recorded the proton pulse measurement (Fig. 3).
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CERN's beams- department engineers worked with the OPERA team to provide a travel time measurement between the source at CERN and a point just before the OPERA detector's electronics, using accurate GPS receivers. This included timing the proton beams' interactions at CERN, and timing the creation of intermediate particles eventually decaying into neutrinos (see Fig. 3). Researchers from OPERA measured the remaining delays and calibrations not included in the CERN calculation: those shown in Fig. 4\. The neutrinos were detected in an underground lab, but the common clock from the GPS satellites was visible only above ground level.
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The advance announcement of the leap second is applied as soon as the message is received, instead of waiting for the correct date. A workaround has been described and tested, but if the GPS system rebroadcasts the announcement, or the unit is powered off, the problem will occur again. On January 21, 2015, several models of GPS receivers implemented the leap second as soon as the announcement was broadcast by GPS, instead of waiting until the implementation date of June 30. The NTP protocol specifies a flag to inform the receiver that a leap second is imminent.
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225x225px Contents of a Geocache For the traditional geocache, a geocacher will place a waterproof container containing a log book (with pen and/or pencil) and trade items or trackables, then record the cache's coordinates. These coordinates, along with other details of the location, are posted on a listing site (see list of some sites below). Other geocachers obtain the coordinates from that listing site and seek out the cache using their handheld GPS receivers. The finding geocachers record their exploits in the logbook and online, but then must return the cache to the same coordinates so that other geocachers may find it.
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A Selective Availability Anti-spoofing Module (SAASM) used by military Global Positioning System receivers to allow decryption of precision GPS observations, while the accuracy of civilian GPS receivers may be reduced by the United States military through Selective Availability (SA) and anti- spoofing (AS). However, on May 1, 2000 it was announced that SA was being discontinued, along with a United States Presidential Directive that no future GPS programs will include it. Before the advent of L2C, AS was meant to prevent access to dual-frequency observations to civilian users. SAASM allows satellite authentication, over-the-air rekeying, and contingency recovery.
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It has even been proposed that in future, it may be possible to deduce the locations of photos purely by comparison with large numbers of geotagged photos. These geotagging techniques rely on post-processing of media, recorded tracks and/or MAC addresses, and cannot be used for real-time geotagging. With the rapid rise of mobile smartphones Smartphone shipments Mobithinking.com which integrate GPS receivers and cameras, and relative market stagnation of separate devices,Kevin J. O'Brien, New York Times, 2010 Nov 15 Smartphone Sales Taking Toll on G.P.S. Devices these phones are the most numerous instruments for autogeotagging.
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The pseudorange (from pseudo- and range) is the pseudo distance between a satellite and a navigation satellite receiver (see GNSS positioning calculation) —for instance Global Positioning System (GPS) receivers. To determine its position, a satellite navigation receiver will determine the ranges to (at least) four satellites as well as their positions at time of transmitting. Knowing the satellites' orbital parameters, these positions can be calculated for any point in time. The pseudoranges of each satellite are obtained by multiplying the speed of light by the time the signal has taken from the satellite to the receiver.
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If there is stereo, there will typically be a guard band between the upper limit of the DSBSC stereo signal (53 kHz) and the lower limit of any other subcarrier. Digital services are now also available. A 57 kHz subcarrier (phase locked to the third harmonic of the stereo pilot tone) is used to carry a low-bandwidth digital Radio Data System signal, providing extra features such as station name, Alternative Frequency (AF), traffic data for commercial GPS receivers and Radio text (RT). This narrowband signal runs at only 1,187.5 bits per second, thus is only suitable for text.
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RF CMOS is a metal–oxide–semiconductor (MOS) integrated circuit (IC) technology that integrates radio-frequency (RF), analog and digital electronics on a mixed-signal CMOS (complementary MOS) RF circuit chip. It is widely used in modern wireless telecommunications, such as cellular networks, Bluetooth, Wi-Fi, GPS receivers, broadcasting, vehicular communication systems, and the radio transceivers in all modern mobile phones and wireless networking devices. RF CMOS technology was pioneered by Pakistani engineer Asad Ali Abidi at UCLA during the late 1980s to early 1990s, and helped bring about the wireless revolution with the introduction of digital signal processing in wireless communications.
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Wongan Hills is a town in the Shire of Wongan-Ballidu, in the Wheatbelt region of Western Australia. The town is approximately 182 km north of the state capital Perth, at an altitude of 286 metres. The town is named for a nearby range of hills that are found to the north-west of the town, also named Wongan Hills, which was first recorded in 1836 by Surveyor General of Western Australia John Septimus Roe. As part of Easter celebrations in 2009, a cross was laid out in a bare paddock using 460 half-tonne hay bales with the aid of GPS receivers.
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The extent of tephra deposits would depend on wind strength and directions. However, given the sudden nature of rockfall-avalanches, these would be more dangerous than pyroclastic flows or tephra, as they could occur without warning, seriously endangering life within of the Crags. The Chaos Crags are monitored for movement in case of future rockslides by the United States Geological Survey; GPS receivers have been in place to monitor deformation within the Lassen volcanic center since 2008. 13 seismometers in the vicinity, first installed in 1976 and since updated each decade, continually survey earthquakes within the locale.
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By the mid-1990s, the larger GPS manufacturing companies created GPS receivers that were smaller, more energy- efficient, and therefore more usable for animal-tracking applications. GPS tracking devices are often linked to an Argos Platform Transmitter Terminal (PTT) enabling them to transmit data via the Argos System, a scientific satellite system which has been in use since 1978. Users can then download their data directly from Argos via telnet and process the raw data to extract their transmitted information. Data can also be transmitted via GSM networks, using SMS messages or internet protocols in a GPRS session.
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With the advent of The Information Age and the accompanying mobile technology, GPS has become a ubiquitous and life-changing technology to all sectors, critical even. For example, current cell phones include GPS receivers, and when used in conjunction with GIS like Google Maps, accurate and real-time directions can be used by pedestrian and civilian traffic alike. Indeed, with GPS, airplanes are now capable of landing on autopilot, and doing so with better precision and safety than human pilots. Outside of military and standard civilian use, seismologists are testing GPS for use in earthquake detection and measurement.
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A modern sailing boat, or any other modern seagoing craft, is a much more complex electronic environment than ever in the past, and even more so than a normal home-based amateur radio "shack". The vessel will probably have electronic navigation instruments, one or more GPS receivers, electronic automatic steering, domestic radio and perhaps television receivers as well as probably radar and VHF transmitters and receivers too. It may have various GMDSS devices too, such as a Navtex receiver and an AIS system. Many of these items are computerised and many of them are networked together with data, RF and power connections.
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These signals are broadcast on marine longwave frequencies, which could be received on existing radiotelephones and fed into suitably equipped GPS receivers. Almost all major GPS vendors offered units with DGPS inputs, not only for the USCG signals, but also aviation units on either VHF or commercial AM radio bands. They started sending out "production quality" DGPS signals on a limited basis in 1996, and rapidly expanded the network to cover most US ports of call, as well as the Saint Lawrence Seaway in partnership with the Canadian Coast Guard. Plans were put into place to expand the system across the US, but this would not be easy.
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The DAG produces 64 bit timestamps in fixed-point format with 32 fractional bits, giving a potential precision of 2^{-32} seconds or 233 picoseconds. The actual precision offered varies with the particular model of DAG, the oldest giving 24 fractional bits (60 nanoseconds) and better precisions offered in DAGs for higher bandwidth networks. The timestamp is derived from a free-running clock provided by a crystal oscillator but the accuracy of crystals drift with both temperature and age. The DAG's solution is to use direct digital synthesis using the 1 Hz pulse- per-second output that many GPS receivers provide as its reference clock.
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With the advent of widespread Global Positioning System (GPS) applications came the introduction of a GPS-based traffic preemption system, that could also do collision avoidance. Recently some GPS preemption systems have found a way to overcome the nagging problem that "blinds" many GPS systems: how to prevent the system from being "blinded" by the loss of a GPS signal. In dense cities with tall buildings, GPS receivers may have difficulty obtaining the four required GPS satellite signals, required for trilateration to determine location. If the vehicle systems are not designed with a backup "IMU" (Inertial Measurement Unit), lack of GPS availability may adversely affect the system's performance.
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The traditional bottle dynamo (pictured) is not actually a dynamo at all (which creates DC power), but a low-power magneto that generates AC. Newer models can include a rectifier to create DC output to charge batteries for electronic devices including cellphones or GPS receivers. Named after their resemblance to bottles, these generators are also called sidewall dynamos because they operate using a roller placed on the sidewall of a bicycle tire. When the bicycle is in motion and the dynamo roller is engaged, electricity is generated as the tire spins the roller. Two other dynamo systems used on bicycles are hub dynamos and bottom bracket dynamos.
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Desktop computers and laptops are commonly targeted to gather passwords or financial account information, or to construct a botnet to attack another target. Smartphones, tablet computers, smart watches, and other mobile devices such as quantified self devices like activity trackers have sensors such as cameras, microphones, GPS receivers, compasses, and accelerometers which could be exploited, and may collect personal information, including sensitive health information. WiFi, Bluetooth, and cell phone networks on any of these devices could be used as attack vectors, and sensors might be remotely activated after a successful breach. The increasing number of home automation devices such as the Nest thermostat are also potential targets.
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In fact, most modern cell phones have built in GPS receivers. If a climber calls 911, the cell phone may automatically provide emergency services with the climber's GPS coordinates. Cell phones also allow the lost or injured climber to provide important information to rescuers, such as the nature of any injuries; however, cell phone coverage on Mount Hood can be spotty and they are therefore not necessarily a replacement for other technologies such as PLBs which leverage satellites overhead for communication. Oregon State Representative John Lim (R) introduced House Bill 2509, which would require climbers to use an electronic signaling device when climbing above 10,000 feet between November and March.
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The versatility of time-transfer systems such as GPS receivers (here assumed to provide PPS and 10 MHz signals) as well as other similar systems allows for phase and frequency coordination among the transmitters. The guard interval allows for a timing budget, of which several microseconds may be allocated to time errors of the time- transfer system used. A GPS receiver worst-case scenario is able to provide +/- 1 µs time, well within the system needs of DVB-T SFN in typical configuration. In order to achieve the same transmission time on all transmitters, the transmission delay in the network providing the transport to the transmitters needs to be considered.
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The baseband processors and radio transceivers in all modern wireless networking devices and mobile phones are mass-produced using RF CMOS devices. RF CMOS circuits are widely used to transmit and receive wireless signals, in a variety of applications, such as satellite technology (including GPS and GPS receivers), Bluetooth, Wi-Fi, near-field communication (NFC), mobile networks (such as 3G and 4G), terrestrial broadcast, and automotive radar applications, among other uses. Examples of commercial RF CMOS chips include Intel's DECT cordless phone, and 802.11 (Wi-Fi) chips created by Atheros and other companies. Commercial RF CMOS products are also used for Bluetooth and Wireless LAN (WLAN) networks.
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Measurements from the reference stations are routed to master stations, which queue the received Deviation Correction (DC) and send the correction messages to geostationary WAAS satellites in a timely manner (every 5 seconds or better). Those satellites broadcast the correction messages back to Earth, where WAAS-enabled GPS receivers use the corrections while computing their positions to improve accuracy. The International Civil Aviation Organization (ICAO) calls this type of system a satellite-based augmentation system (SBAS). Europe and Asia are developing their own SBASs, the Indian GPS Aided Geo Augmented Navigation (GAGAN), the European Geostationary Navigation Overlay Service (EGNOS) and the Japanese Multi-functional Satellite Augmentation System (MSAS), respectively.
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Obstructed lines of sight may arise from a tree canopy or inside a structure, such as in a building, garage or tunnel. Today, most standalone GPS receivers are used in automobiles. The GPS capability of smartphones may use assisted GPS (A-GPS) technology, which can use the base station or cell towers to provide a faster Time to First Fix (TTFF), especially when GPS signals are poor or unavailable. However, the mobile network part of the A-GPS technology would not be available when the smartphone is outside the range of the mobile reception network, while the GPS aspect would otherwise continue to be available.
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In 1990 he moved to Trimble Navigation, where he participated in efforts to embed the new satellite based navigation GPS into airplanes and with additional equipment enable them for blind landing. During the last two years at Trimble Navigation France was heavily involved with attempts to redesign and then integrate the GPS receiver into only two chips. This effort led him to join his two coworkers who established a new company called eRide Inc. Their goal was to design novel GPS receivers, which would make it possible to navigate under diverse condition such as inside the buildings or in other reflective environments but primarily inside a wristwatch.
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More recently, high- performance devices have become more compact, and multimedia computer capabilities are found in mobile devices such as the Apple iPhone and Nokia Nseries, featuring DVD-like video quality, megapixel class cameras, fully capable browser, music and video players, podcasting, blogging, as well as e-mail, instant messaging, presence and internet call (VoIP) functionality. Multiradios help to offer broadband wireless connectivity, including for instance WCDMA/HSDPA and WLAN/Wifi. Devices are also increasingly equipped with GPS receivers and maps applications, providing new capabilities for location-aware services. The Nseries devices are also expandable, allowing for the addition of multiple applications and multimedia content.
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On March 23, 2003, a convoy of the United States Army's 507th Maintenance Company and the 3rd Combat Support Battalion elements, led by a Humvee driven by Lori Piestewa, made a wrong turn and were ambushed near Nasiriyah, a major crossing point over the Euphrates northwest of Basra. The convoy was supposed to detour around the town but instead turned directly into it, eventually running into an ambush. The ambush was unlikely to have been set up in advance, because the Iraqis did not know which course the convoy would take. Although some vehicles had GPS receivers, military GPS systems, unlike civilian equivalents, provide only grid references and not turn-by-turn navigation.
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This technique, known as "Selective Availability", or SA for short, seriously degraded the usefulness of the GPS signal for non-military users. More accurate guidance was possible for users of dual-frequency GPS receivers which also received the L2 frequency (1227.6 MHz), but the L2 transmission, intended for military use, was encrypted and was available only to authorized users with the decryption keys. This presented a problem for civilian users who relied upon ground-based radio navigation systems such as LORAN, VOR and NDB systems costing millions of dollars each year to maintain. The advent of a global navigation satellite system (GNSS) could provide greatly improved accuracy and performance at a fraction of the cost.
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The concepts are different but not mutually exclusive; so a watch can be a chronograph, a chronometer, both, or neither. Timex Datalink USB Dress edition from 2003 with a dot matrix display; the Invasion video game is on the screen Many computerized wristwatches have been developed, but none have had long-term sales success, because they have awkward user interfaces due to the tiny screens and buttons, and short battery life. As miniaturized electronics became cheaper, watches have been developed containing calculators, tonometers, barometers, altimeters, a compass using both hands to show the N/S direction, video games, digital cameras, keydrives, GPS receivers and cellular phones. A few astronomical watches show phase of the Moon and other celestial phenomena.
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The utility of almost every large or medium scale map (paper or electronic) can be greatly enhanced by having an overlaid coordinate grid. The USNG provides such a grid that is universal, interoperable, non-proprietary, works across all jurisdictions, and can readily be used with GPS receivers and other location service applications. In addition to providing a convenient means to identify and communicate specific locations (points and areas), an overlaid USNG grid also provides an orientation, and—because it is distance based—a scale of distance that is present across the map. USGS topographic maps have for decades been published with 1000-meter UTM tick marks in the map collar, and sometimes with full grid lines across the map.
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As a result, additional surveys using the Global Positioning System took place in 2004, and further InSAR surveys showed that subsidence continued through 2010. Lassen Peak is one of four Cascade volcanoes that has undergone subsidence since 1990, with Medicine Lake Volcano, Mount Baker, and Mount St. Helens. Though not conclusively linked to a possible eruption, this subsidence may offer insight into how magma is stored within the region, tectonic setting, and how hydrothermal systems evolve over long periods of time. GPS receivers have been in place to monitor deformation within the Lassen volcanic center since 2008, and 13 seismometers in the vicinity, first installed in 1976 and since updated each decade, continually survey earthquakes within the locale.
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There is a serious practical problem with this approach - in order to measure the time it took for the signals to reach the receiver, the receiver must know the precise time that the signal was originally sent. This is not possible in the case of uncooperative signal sources (like enemy artillery) and even in modern times, GPS receivers with atomic clocks synchronized to the spacecraft are very rare. In the 1930s, such precise time measurements simply weren't possible; a clock of the required accuracy was difficult enough to build in fixed form, let alone portable. A high-quality crystal oscillator, for instance, drifts about 1 to 2 seconds in a month, or .
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Laser projected from the Royal Observatory in Greenwich, marking the Prime meridian. The plane of the prime meridian is parallel to the local gravity vector at the Airy transit circle () of the Greenwich observatory. The prime meridian was therefore long symbolised by a brass strip in the courtyard, now replaced by stainless steel, and since 16 December 1999, it has been marked by a powerful green laser shining north across the London night sky. Global Positioning System (GPS) receivers show that the marking strip for the prime meridian at Greenwich is not exactly at zero degrees, zero minutes, and zero seconds but at approximately 5.3 seconds of arc to the west of the meridian (meaning that the meridian appears to be 102.478 metres east).
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The post-processed measurements allow more precise positioning, because most GPS errors affect each receiver nearly equally, and therefore can be cancelled out in the calculations. Differential GPS measurements can also be computed in real time by some GPS receivers if they receive a correction signal using a separate radio receiver, for example in Real Time Kinematic (RTK) surveying or navigation. The improvement of GPS positioning doesn't require simultaneous measurements of two or more receivers in any case, but can also be done by special use of a single device. In the 1990s when even handheld receivers were quite expensive, some methods of quasi-differential GPS were developed, using the receiver by quick turns of positions or loops of 3-10 survey points.
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Cellular geolocation is less precise than by GPS, but it is available to devices that do not have GPS receivers and where the GPS is not available. The precision of this system varies and is highest where advanced forward link methods are possible and is lowest where only a single cell site can be reached, in which case the location is only known to be within the coverage of that site. An advanced forward link is where a device is within range of at least three cell sites and where the carrier has implemented timing system use. Another method is using angle of arrival (AoA) and it occurs when the device is in range of at least two cell sites, produces intermediate precision.
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The Plate Boundary Observatory PBO consists of a series of geodetic instruments, Global Positioning System (GPS) receivers and borehole strainmeters, that have been installed to help understand the boundary between the North American Plate and Pacific Plate. The PBO network includes several major observatory components: a network of 1100 permanent, continuously operating Global Positioning System (GPS) stations many of which provide data at high-rate and in real-time, 78 borehole seismometers, 74 borehole strainmeters, 26 shallow borehole tiltmeters, and six long baseline laser strainmeters. These instruments are complemented by InSAR (interferometric synthetic aperture radar) and LiDAR (light detection and ranging) imagery and geochronology acquired as part of the GeoEarthScope initiative. PBO also includes comprehensive data products, data management and education and outreach efforts.
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Use of GIBs for underwater tracking and weapon scoring have been in use by the Navy since the early to mid 1990s. Early GIBs were created for broad ocean area weapons testing by modifying conventional Navy sonobuoys with small OEM-grade GPS receivers and deploying them from a helicopter or from P-3 Orion aircraft.Saunders, J., and Cardoza, M. "Preliminary Results from a GPS-Based Portable Impact Location System", Proceedings of the Institute of Navigation’s Satellite Division Meeting, ION GPS-95, Palm Springs, California, 12-15 September, 1995 The GPS data captured by the GIB was modulated over the analog VHF acoustic data stream using frequency-shift keying (FSK). This allows the GPS measurement data to be transmitted and received on legacy VHF sonobuoy receiver equipment.
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The P(Y)-code is transmitted on both the L1 and L2 frequencies as a 10.23 MHz signal using the same BPSK modulation, however the P(Y)-code carrier is in quadrature with the C/A carrier (meaning it is 90° out of phase). Besides redundancy and increased resistance to jamming, a critical benefit of having two frequencies transmitted from one satellite is the ability to measure directly, and therefore remove, the ionospheric delay error for that satellite. Without such a measurement, a GPS receiver must use a generic model or receive ionospheric corrections from another source (such as the Wide Area Augmentation System or WAAS). Advances in the technology used on both the GPS satellites and the GPS receivers has made ionospheric delay the largest remaining source of error in the signal.
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Benchmark hunters also frequently carry a compass (to follow directions gleaned from the data sheet), a probe (like a long-bladed screwdriver) to search for buried marks, a trowel (or a small shovel) to uncover buried marks, a whisk broom (to clear away debris), and one or more tape measures of various lengths, used in taping out referenced distances found on the data sheets. Handheld GPS receivers are often used to get within a few yards probable error of a mark that has adjusted coordinates. Metal detectors are useful for finding marks which have become deeply buried over time. Use of several of the tools in combination is sometimes required, but many marks are set on the surface of sidewalks, buildings, walls, boulders, or monuments and can often be found without special tools.
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A pulse per second (PPS or 1PPS) is an electrical signal that has a width of less than one second and a sharply rising or abruptly falling edge that accurately repeats once per second. PPS signals are output by radio beacons, frequency standards, other types of precision oscillators and some GPS receivers. M. Siccardi, About time measurements, EFTF 2012 Precision clocks are sometimes manufactured by interfacing a PPS signal generator to processing equipment that aligns the PPS signal to the UTC second and converts it to a useful display. Atomic clocks usually have an external PPS output, although internally they may operate at 9,192,631,770 Hz. PPS signals have an accuracy ranging from a 12 picoseconds to a few microseconds per second, or 2.0 nanoseconds to a few milliseconds per day based on the resolution and accuracy of the device generating the signal.
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The VRay is an 80-element spherical antenna that provides precise positioning in dense urban environments and indoors where traditional GNSS receivers are susceptible to large multipath errors. MIT Technology Review By switching on each element for just over one microsecond, the VRay correlator design in a Locata receiver creates virtual beams which mitigate multipath effects by focusing on the direct received signal and filtering out multipath bounces. Because the VRay can sweep many beams simultaneously around an area it also determines the angle and strength of received signals and this information is used to derive the precise 3D attitude of the receiver platform as well. In a partnership with the U.S. Air Force Institute of Technology (AFIT), the VRay is being developed for use with GPS receivers as part of a Co-operative Research and Development Agreement (CRADA) signed in April 2013.
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In recent years the technology has also become widely available in small aircraft. As aircraft displays have modernized, the sensors that feed them have modernized as well. Traditional gyroscopic flight instruments have been replaced by electronic attitude and heading reference systems (AHRS) and air data computers (ADCs), improving reliability and reducing cost and maintenance. GPS receivers are usually integrated into glass cockpits. Early glass cockpits, found in the McDonnell Douglas MD-80, Boeing 737 Classic, ATR 42, ATR 72 and in the Airbus A300-600 and A310, used Electronic Flight Instrument Systems (EFIS) to display attitude and navigational information only, with traditional mechanical gauges retained for airspeed, altitude, vertical speed, and engine performance. The Boeing 757 and 767-200/-300 introduced an electronic Engine-indicating and crew-alerting system (EICAS) for monitoring engine performance while retaining mechanical gauges for airspeed, altitude and vertical speed.
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Although the GLONASS constellation has reached global coverage, its commercialisation, especially development of the user segment, has been lacking compared to the American GPS. For example, the first commercial Russian-made GLONASS navigation device for cars, Glospace SGK-70, was introduced in 2007, but it was much bigger and costlier than similar GPS receivers. In late 2010, there were only a handful of GLONASS receivers on the market, and few of them were meant for ordinary consumers. To improve the situation, the Russian government has been actively promoting GLONASS for civilian use. To improve development of the user segment, on 11 August 2010, Sergei Ivanov announced a plan to introduce a 25% import duty on all GPS-capable devices, including mobile phones, unless they are compatible with GLONASS. The government also planned to force all car manufacturers in Russia to support GLONASS starting from 2011.
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The ability to superimpose spatially located variables onto existing maps created new uses for maps and new industries to explore and exploit these potentials. See also digital raster graphic. In the early years of the new millennium, three key technological advances transformed cartography: the removal of Selective Availability in the Global Positioning System (GPS) in May 2000, which improved locational accuracy for consumer- grade GPS receivers to within a few metres; the invention of OpenStreetMap in 2004, a global digital counter-map that allowed anyone to contribute and use new spatial data without complex licensing agreements; and the launch of Google Earth in 2005 as a development of the virtual globe EarthViewer 3D (2004), which revolutionised access to satellite and aerial imagery. These advances brought more accuracy to geographical and location-based data and widened the range of applications for cartography, for example in the development of satnav devices.
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In its simplest implementation, APRS is used to transmit real-time data, information and reports of the exact location of a person or object via a data signal sent over amateur radio frequencies. In addition to real-time position reporting capabilities using attached GPS receivers, APRS is also capable of transmitting a wide variety of data, including weather reports, short text messages, radio direction finding bearings, telemetry data, short e-mail messages (send only) and storm forecasts. Once transmitted, these reports can be combined with a computer and mapping software to show the transmitted data superimposed with great precision upon a map display. While the map plotting is the most visible feature of APRS, the text messaging capabilities and local information distribution capabilities, combined with the robust network, should not be overlooked; the New Jersey Office of Emergency Management has an extensive network of APRS stations to allow text messaging between all of the county Emergency Operating Centers in the event of the failure of conventional communications.
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At Harvard Business School he met David Thompson and Scott Webster, with whom in 1982 he co-founded Orbital Sciences Corporation to develop commercial opportunities in space. From 1982 to 1993, in positions that included Senior Vice President, Finance and Administration; General Counsel; and Chief Operating Officer, Ferguson played a role in arranging collaborations and financing for projects such as development of the world’s first privately-funded orbital launch vehicles: the Space Shuttle-launched Transfer Orbit Stage for boosting spacecraft from Shuttle orbit to geosynchronous orbit and planetary trajectories; the aircraft-launched Pegasus for delivering small research and communications spacecraft into low Earth orbit; and the ground-launched Taurus for delivering larger payloads to Earth orbit. From 1993 to his resignation in 1997, Ferguson's was Executive Vice President, Communications and Information Systems Group; his activities included management of Orbital’s Magellan division that built and marketed commercial Global Positioning System (GPS) receivers, Orbcomm's introduction of low-Earth orbit satellite systems, and Orbimage's introduction of commercial Earth remote sensing services.
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On remote control devices, the buttons on the d-pad function in the same manner as other buttons, and are generally used to navigate on-screen menus. Though initially not common, the quick success of the DVD format led to wide availability of remote designs with D-pads circa 2000, and most current menu-driven consumer electronics devices include some sort of d-pad on the remote (and, occasionally, on the unit itself). In addition, many small computing and communications devices, particularly PDAs, mobile phones, and GPS receivers, include d-pads not only for menu navigation but as general input devices similar to a joystick or mouse. Less-sophisticated designs similar to those on remote controls appear on some calculators, particularly scientific and graphing calculators, which use the d-pad for cursor control on multi-line screens, as well as input/output recall, menu navigation, and occasionally direct screen access (graphing calculators in particular allow the use of the d-pad to determine values at specific points on a displayed graph).
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