Overlapping Secondary Surveillance Radar Replies Separation Algorithm Based on MUSIC
Hai Feng Zhang, Xiaolong Chen, Tao Zhang, Caisheng Zhang · 2020
In order to improve the reception performance of Secondary Surveillance Radar (SSR) replies in high-density signal environment, a separation algorithm is proposed, which constructs the separating matrix with estimating the source number and the Direction Of Arrival (DOA) of signal. Firstly, the number of overlapping signals is determined with the eigenvalues distribution of the measurements. Secondly, the mixing matrix with the DOA of signals, which is estimated by peak value searching in MUSIC algorithm. Finally, the separating matrix is estimated by calculating the Moore-Penrose inverse of the reconstructed mixing matrix, achieving separation of overlapping signals. Simulation is done based on uniform linear array with 6 elements. The results show that the proposed separation algorithm can achieve more than 90% success rate to separate two short Mode S replies, and the separating performance is similar to the Independent Component Analysis (ICA) algorithm and is better than Projection Algorithm (PA). The amount of calculation is less than 10 percent of ICA algorithm, thus the proposed separation algorithm is easier to engineering application.