Abstract:

Under the battlefield environment, the intermodulation interference produced by the spacecompressed frequency equipment brings serious distortion to the signals and affects the normal operation of the C3 system. Focusing on the intermodulation interference between the frequency hopping (FH) radios working on the VHF band, the time, frequency and power conditions are analyzed, and the FH radio’s random location and the shadowing effects are also included. Three conditional probabilities that determine the intermodulation interference probability are studied, which respectively are, probability of the availability of two or more active frequency channels; probability that the frequencies of the active channels satisfy the intermodulation interference frequency condition; and probability that the active channel signal powers satisfy the intermodulation interference power condition. The simulation results for the probability of two and three signals 3rd order intermodulation interference are presented. A method for FH radio intermodulation interference probability estimation based on Monte-Carlo method is proposed. The simulation results show that, the proposed method can estimate the intermodulation interference probability effectively, and it can provide reference for the electronic warfare simulation and the operational command in the battlefield.