Multiple wideband radiation sources direction finding algorithm under background of interference

In electronic countermeasures, in order to interfere the normal work of reconnaissance receiver, the noise signal emitted by the jammer is usually used for electromagnetic suppression. Otherwise, the radar signal may be exist in the reality electromagnetic environment. Signals can not be recognized in time domain because of the superposition of interference signal and radar signal. The directions of them can not be found. So it is important to have the research on the detection and direction finding (DF) algorithm of mixed signals under the background of interference. The algorithm in this paper is considered in the frequency domain. The signals can be detected and recognized according to the maximum values and mean square values of spectral modulus after the short time Fourier transform (STFT). Then the direction can be found by the interception of the useful data segment. The equipment is simple in this algorithm. Its amount of computation is less and it is suitable for the project realization. The directions of interference signal and radar signal can be found simultaneously. Computer simulation results show that high accuracy can be achieved on certain conditions.