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A universal LNB has a switchable local oscillator frequency of 9.75/10.60 GHz to provide two modes of operation: low band reception (10.70–11.70 GHz) and high band reception (11.70–12.75 GHz). The local oscillator frequency is switched in response to a 22 kHz signal superimposed on the supply voltage from the connected receiver.
In communications, a system is wideband when the message bandwidth significantly exceeds the coherence bandwidth of the channel.Some communication links have such a high data rate that they are forced to use a wide bandwidth; other links may have relatively low data rates, but deliberately use a wider bandwidth than "necessary" for that data rate in order to gain other advantages; see spread ...
Special LNBs have been developed for use in single-cable distribution systems. All four sub-bands of the Ku band (low frequency/horizontal polarity, high frequency/horizontal polarity, low frequency/vertical polarity, high frequency/vertical polarity) are received by a conventional front end, amplified and downconverted to the L-band, to be fed to a number of SatCR (Satellite Channel Router ...
In the box at the focus of the dish, called a low-noise block downconverter (LNB), each block of frequencies is converted to the IF range of 950–2150 MHz by two fixed frequency local oscillators at 9.75 and 10.6 GHz. One of the two blocks is selected by a control signal from the set top box inside, which switches on one of the local oscillators.
TFCs 1-4 are for TFI channels, TFCs 5-7 are for FFI channels, and TFCs 8-10 are for TFI2 channels, which simply interleave their data across two bands. Note that all TFCs will be in the same band at some time during their sequence. TFC numbering of 1-10 repeats for each band group and these TFC numbers are primarily used by the MAC and PHY layers.
Techniques known since the 1940s and used in military communication systems since the 1950s "spread" a radio signal over a wide frequency range several magnitudes higher than minimum requirement. The core principle of spread spectrum is the use of noise-like carrier waves, and, as the name implies, bandwidths much wider than that required for ...
The sub-gigahertz band, which contains only 1 channel and ranges from 249.6 MHz to 749.6 MHz. The low band, which contains 4 channels and ranges from 3.1 GHz to 4.8 GHz. The high band, which contains 11 channels and ranges from 6.0 GHz to 10.6 GHz. The primary time division in UWB systems is structured in frames. Each frame is composed by the ...
A multiswitch is a device used with a dual or quattro LNB to distribute satellite TV signals to multiple (usually more than four) receivers from a single dish and LNB. A typical K u band universal LNB designed for the European market can be switched between four modes (two frequency ranges and two polarisations) selected by signals from the ...