| 摘要 |
A single sideband receiver translates the frequencies of a received signal composed of a data signal and a pilot tone to predetermined intermediate frequencies. Filters separate the intermediate frequency data signal and the intermediate frequency pilot tone. The frequency of the intermediate frequency pilot tone is translated to a frequency sufficiently removed from the frequency spectrum of the intermediate frequency data signal so as not to interfere therewith. The translated, intermediate frequency, pilot tone and the intermediate frequency data signal are amplified by a single automatic gain controlled amplifier. A demodulator produces audio output signals and a recovered pilot tune in response to the output signal of the amplifier. The recovered pilot tone is input to a pilot regenerator. The output signal of the pilot regenerator is input to the demodulator. The recovered pilot tone is also input to an automatic gain control circuit. The automatic gain control circuit together with a gain limiter control the gain of the amplifier.
|
