Prediction analysis of the electromagnetic interfering signal in communication systems

This paper is devoted to investigation on prediction analyzing of the electromagnetic interfering signal in communication systems. In this paper, we proposed the concept of mathematical model group, and discussed the problem from several aspects which is listed below: frequency band of the transmitter, clutter and harmonic model of the receiver, the radiation power of the receiver, the modulation envelope curve, the frequency selection curve of the receiver, the correction factor of frequency interval and frequency selection, the susceptibility threshold, and the interfering signal power. When the frequency of the clutter approached the affected receiver´s working frequency f_R, it would form a sort of interference which affect the receiver. If the complementary wave of the interference of FIM, RIM, TIM and SIM is less than -20 db, it could be regarded that no interference exists. Otherwise, it could be regarded that the interference exists, and some measure must be used to eliminate the interference.