Modeling And Simulation Reserchs On Communication Direction Finding Technology

Direction finding is one of the most important parts in the communication countermeasure. With the development of communication technology, the communication signal environment is getting more and more complex. FH (frequency hopping) signal is used widely in the battlefield, and direction finding becomes an important method to get communication information. Restricted by the long period, high cost and condition, the computer simulation is used to evaluate the communication countermeasure and direction finding rather than making hardware experiments.The models of interferometer direction finding and MUSIC are given by MATLAB/SIMULINK based on their respective principles. Then the simulation system of communication direction finding is mentioned and the performance of the system in different conditions is analyzed, at last the direction finding federation member is illuminate. Three sections are consisted in this thesis. In the first section, the interferometer direction finding model is constructed, the influence that is caused by SNR, baseline, signal frequency and I/Q imbalance is analyzed and a model that can eliminate the influence of I/Q imbalance is put forward. In the third section, the simulation on MUSIC direction finding and the influence that is caused by SNR, space between antennae, signal frequency and channel mismatch is analyzed. According to the single known-direction source calibration method, the channel mismatch is calibrated.In the last, the thesis research content is summarized, and some problems to be studied in future are also put forward.