摘要 |
<p>An interference compensation system comprises a first input for receiving an interference signal IA and a second input for receiving a desired signal and an interference signal IM. An amplitude-phase control circuit adjusts the amplitude and phase of interference signal IA so that the amplitude and the phase of the output signal IVM of the amplitude phase control circuit are the same amplitude and the opposite phase as compared with the interference signal IM. The output signal IVM of the amplitudephase control circuit and the signal IM are combined to provide a compensated output signal IE substantially free from the interference signal. The control signal is subject only to the amplitude change or the power change of the input high frequency signal, and that control signal is obtained after envelope detection is performed. Therefore, the interference compensation is accomplished satisfactorily irrespective of the modulation method of both the desired signal and the undesired interference signal. Thus, PSK signals, and FM signals are much better compensated for than in most prior art arrangements. Further, because of the presence of the amplitude-phase control circuit which controls both the amplitude and the phase of the interference signal, and determines not only the direction of the variable to be controlled but also the amount of the variable to be controlled at the same time, a compensation control having excellent response characteristics is achieved.</p> |