But owing to insufficient funding and a row with the F.C.C., which Amtrak said had been slow to approve the use of the requisite radio bandwidth, its actual implementation has been piecemeal.
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A key goal will be to test the Sprites' communications system, which relies on a protocol called code division multiple access (CDMA)—the same method that a cellphone tower uses to talk to hundreds of individual devices over the same radio bandwidth.
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When the hiring manager explained how the intern didn't give enough positive updates, I knew exactly what was happening: in the military, you don't use valuable radio bandwidth to say "We're doing great!" when someone else might need that channel for a MEDEVAC at any moment.
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Such pictures would have required considerable radio bandwidth. The pictures would be incompatible with the pre- war, EMI / BBC, 405-line system. Before the Hankey Committee, Baird also considered the possibility of compatible color systems. In December 1944, the committee delivered its preliminary report.
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Each radio transmission occupies a portion of the total bandwidth available. Radio bandwidth is regarded as an economic good which has a monetary cost and is in increasing demand. In some parts of the radio spectrum the right to use a frequency band or even a single radio channel is bought and sold for millions of dollars. So there is an incentive to employ technology to minimize the bandwidth used by radio services.
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Later was introduced GPRS (general packet radio service), which operates on completely different principle. It also can use multiple time slots for transfer, but it does not tie up radio resources, when not transferring data (as opposed to CSD and like). GPRS usually is prioritized under voice and CSD, so latencies are large and variable. Later, GPRS was upgraded to EDGE, which differs mainly by radio modulation, squeezing more data capacity in same radio bandwidth.
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Rowe has also created a frequency-division multiplex (FDM) modem which carries the digital voice (DV) in only 1.3 kHz of radio bandwidth. The codec and FDM modem are used every day on amateur radio shortwave bands using both the SM1000 hardware implementation, and the FreeDV application. This modem operates at 50 Baud with a bit rate of 1600 bit/s. This is sent using sixteen QPSK FDM carriers (2 bits each), or 32 bits 50 times a second.
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The infrastructure layer represents the actual physical network topology (radio access network, transport network and core network) upon which every network slice is multiplexed and it provides the physical network resources to host the several network functions composing each slice. The network domain of the available resources includes a heterogeneous set of infrastructure components like data centers (storage and computation capacity resources), devices enabling network connectivity such as routers (networking resources) and base stations (radio bandwidth resources).
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In packet radio wireless networks, The fairly shared spectrum efficiency (FSSE) can be used as a combined measure of fairness and system spectrum efficiency. The system spectral efficiency is the aggregate throughput in the network divided by the utilized radio bandwidth in hertz. The FSSE is the portion of the system spectral efficiency that is shared equally among all active users (with at least one backlogged data packet in queue or under transmission). In case of scheduling starvation, the FSSE would be zero during certain time intervals.
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Other claims of the switch were that it was unwiring. As the upcoming of more mobile devices came about, connections were needed for the data network, and bandwidths were required and deliverable in wired or fibre-optic systems growth. It became steadily less sensible to use wireless broadcast as a way of communicating with static installations. At some point the switch takes place, as the limited radio bandwidth is reallocated to data service to mobile equipment, and television and other media move to cable.
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It avoids the chance of misunderstood messages because of busy radio chatter or variations in the way people speak, and it can be a backup if a microphone malfunctions. It also preserves radio bandwidth when voice communication is necessary or preferred. Using Data Comm, tower air traffic controllers can send pilots of equipped aircraft departure clearance instructions to read, accept, and load into their flight management system with the push of a button. Messages also are sent to flight dispatchers, giving everyone a shared awareness for faster reactions to changing circumstances, such as approaching thunderstorms.
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Transmitting signals wirelessly requires the product to be tested to relevant standards for wireless license exemption, these products are generally limited to 100 mW (10 mW in the UK) and for higher power models, used generally within the broadcasting industry, a licence is required. If the broadcast is across LAN or via similar IP technologies, such as the internet, then using streaming technology does not require a license. The regulator is the Federal Communications Commission (FCC) in the United States who are responsible for the efficient use of radio bandwidth.
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Also around this time, the Internal Revenue Service began investigating him for tax fraud. He declared bankruptcy in 1941, the same year the U.S. and Mexico reached an agreement on allocating radio bandwidth and shut down XERA. Soon after his bankruptcy the U.S. Post Office Department began investigating him for mail fraud, and Brinkley became a patient himself, having suffered three heart attacks and the amputation of one of his legs due to poor circulation. On May 26, 1942, Brinkley died penniless of heart failure in San Antonio; the mail fraud case had not yet come to trial.
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Unlike spread spectrum, UWB transmits in a manner that does not interfere with conventional narrowband and carrier wave transmission in the same frequency band. Ultra-wideband is a technology for transmitting information spread over a large bandwidth (>500 MHz); this should, in theory and under the right circumstances, be able to share spectrum with other users. Regulatory settings by the Federal Communications Commission (FCC) in the United States intend to provide an efficient use of radio bandwidth while enabling high-data-rate personal area network (PAN) wireless connectivity; longer-range, low-data-rate applications; and radar and imaging systems.
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Patrol Special Police provide a variety of services for private clients pursuant to a negotiated contract, including unlocking or securing doors to a business, making checks of residences or businesses, conducting perimeter checks at burglar alarms, providing a physical presence at businesses and providing security consultations. Officers concentrate on order maintenance, rapid response, and early intervention in quality-of-life matters. Their goal is to prevent disturbances from becoming expensive and serious crimes, and to relieve pressure on the public police. Since 1994 officers operate with citizens' powers of arrest, are on police radio bandwidth, and are trained annually for 24 hrs.
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Image resolution of SAR in its range coordinate (expressed in image pixels per distance unit) is mainly proportional to the radio bandwidth of whatever type of pulse is used. In the cross-range coordinate, the similar resolution is mainly proportional to the bandwidth of the Doppler shift of the signal returns within the beamwidth. Since Doppler frequency depends on the angle of the scattering point's direction from the broadside direction, the Doppler bandwidth available within the beamwidth is the same at all ranges. Hence the theoretical spatial resolution limits in both image dimensions remain constant with variation of range.
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An InterCity 125 in original British Rail livery near Chesterfield Modern remote control systems are now based on digital signal technology, with most using Time-division multiplexing transmission to cut-down on the number of cables or radio bandwidth required for integrated control. The UK's InterCity 125 was the first passenger train to use TDM technology, introduced from 1976 to allow it to control up to eight carriages sandwiched between two Class 43 power cars. Locotrol is a product of GE Transportation Systems that enables distributed power sending signals from the lead locomotive to the remote units via radio control. Locotrol is installed on more than 8,500 locomotives around the world.
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Lunar Module Eagle at the start of the first lunar EVA Apollo 11 was the spaceflight that landed the first two people on the Moon. Neil Armstrong became the first person to step onto the lunar surface on July 21, 1969, at 02:56 UTC; Buzz Aldrin joined him 19 minutes later. Only limited radio bandwidth was available to transmit the video signal from the lunar landings, which needed to be multiplexed with other communication and telemetry channels beamed from the Lunar Module Eagle, back to Earth. Therefore, Apollo 11's moonwalk video was transmitted from the Apollo TV camera in a monochrome SSTV format at 10 frames per second (fps) with 320 lines of resolution, progressively scanned.
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On top of the Socialist Party's financial troubles came regulatory problems with the FRC, which on May 25, 1928 demanded that WEVD and 163 other stations show cause why their broadcasting licenses should not be revoked as part of a plan to rationalize the distribution of radio bandwidth by forcing out small stations catering to niche audiences in favor of fewer high powered stations broadcasting commercially to a mass market. Representatives of WEVD and 109 other threatened stations made their way to Washington, D.C. in July 1928 for two weeks of regulatory hearings on the issue. Station manager Gerber responded with a statement emphasizing the importance of defending free speech and the right of political minorities to submit their ideas to a broad public.Godfried, "Legitimizing the Mass Media Structure," pg. 130.
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Location of the Grand Duchy of Luxembourg (circled), illustrating its proximity to other countries. On 19 December 1929 the Grand Duchy of Luxembourg established a state monopoly on broadcasting, but the law provided for possible concessions to private companies who wanted to use radio bandwidth, with the state charging a fixed amount for private use of radio. The Société Luxembourgeoise d'Études Radiophoniques (SLER) was founded on 11 May 1929 with the aim of obtaining an eventual broadcasting contract from the Luxembourg government. This company was run by Luxembourger François Anen, French publisher Henry Etienne, and French engineer Jean le Duc representing the Compagnie des Compteurs de Montrouge, which possessed 84% of the project's capital and had signed a secret agreement to work with the group CSF, the main stockholder in Radio Paris.
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