Research On Joint Space-time Adaptive Antenna Anti-Jamming

Space-time interference suppression technology results from the fact that the traditionalspatial filtering has turned out to be incapable of effectively suppressing the large numbers ofwideband interference and multipath interference, mainly because the degree of freedom insuppressing wideband interference signals is much greater than in suppressing narrowbandinterference, and the anti-jamming method is unable to provide too much degree of freedom.Space-time adaptive processing (STAP) is a method to analyze the signals in space and timedomain, which can provide a greater degree of freedom without increasing the antennaelements to suppress more interference signals, especially the wideband interference. Theoptimal algorithm must be selected to get the best effect in space-time processing. To meet thedifferent object, different algorithms should be chosen to achieve the best anti-jammingperformance. In terms of the spatial and temporal filtering, space-time adaptive processingneeds to achieve a larger scale data operation, which will make it difficult to achieve withhardware. So how to make the computation reduced and the interference effect unchanged,which is important to the study of space-time signal processing.With a deep study on the adaptive algorithm and the adaptive anti-jamming technology,and the performance of them, the dissertation is to strengthen the anti-jamming capability ofsatellite navigation receiver antenna. By combining analyzing of the theory and simulatingwith software, the performance of selected geometry of antenna and algorithm was verified.Achievements were summarized as follows：Firstly, the dissertation proposed a new geometry design of antenna for satellitenavigation receiver. On this basis, the corresponding mathematical model with the adaptiveanti-jamming capability was built, and the spatial anti-jamming capability technology wasachieved by the power inversion algorithm. Compared with the traditional uniform circulararray, the new geometry has superior performance on anti-jamming.Secondly, in terms of the certain limitation of the traditional MUISC algorithm on thedirection of arrival estimation and the power inversion algorithm on the adaptiveanti-jamming, the dissertation proposed an improve power inversion algorithm (IPIA). Theimprove algorithm can estimate the weak signal direction more accurately depending on the different subspace between the strong signal and weak signal, and amend the weightadaptively with the recursive computation. The algorithm has the higher SINR.Thirdly, considered the possible angular error on the direction of arrival estimation, thedissertation proposed a robust improve power inversion algorithm (RIPIA). According theestimated error, the algorithm can search the real direction adaptively.Finally, for the limitation of spatial processing, the dissertation discussed the advantagesof the space-time processing. The capability of anti-jamming in space domain of RIPIA waspromoted in space-time domain, the dissertation put forward a space-time robust improvepower inversion algorithm (ST-RIPIA). ST-RIPIA achieves wideband interferencesuppression better and has the good convergence and misadjustment.