| 摘要 |
<p>The stabilization of the coupling value between transmitted radio signals resulting from cross polar discrimination and using transmit power level control in radio link systems formed of several radio channels and using multilevel QAM modulation, is basically comprised of: - means to derive a first control signal for each RF channel in each receiver, and a second control signal for the adjacent channels, - means to combine that 1st and 2nd control signals to derive threshold signals, - means to multiplex all of the threshold signals of the individual receivers, - means to insert a station identification signal in the multiplexer, - means to further multiplex the multiplexed signal with other service signals, - means to insert this dual-multiplexed signal in the frame of the main information signal transmitted in the other direction of transmission, - means to receive and demultiplex the received signal two times, - means to process this demultiplexed signal so as to derive, a transmit power remote control signal and the station identification signal, - means to evaluate exceptional atmospheric precipitation conditions, - means to sumultaneously derive a transmit power local control signal, - means to apply the said control signals to the pre-distortion circuits that are part of the power amplifiers of the transmitters.</p> |
