The Research Of Space-time Adaptive Processing In Anti-jamming Antenna

In recent years, with the development of science and technology, signal in adaptive array signal processing is increasingly inclined to broadband. Compared to narrow-band signal processing, wideband signal processing is more complicated, for it occupys a certain bandwidth. In order to form the consistent beam shape, wideband signal processing needs more freedom. There are two ways to solve this problem; one is the space-time adaptive processing; it adds a time-domain processing to the basis of the spatial domain and process signals from different directions in space-time domain. Another one is parallel processing in frequency domain; it converts the signal to the frequency domain by Fourier transform and processes each frequency data independently.Signal model and array model is the basis of this paper. On the one hand, as narrowband and broadband beamforming have consistent conclusion, the study of algorithm’s robustness starts from Minimum Variance Distortionless Response(MVDR) in narrowband array signal processing. The robustness against quick jitter sorce and sorce location error is obtained via a method which combines the broadening nulling technique based on the statistical model and diagonal loading technique in the worst case. Aiming at the loss of depth nulling, a new weight vector computing model is proposed, which can adjust the beam shape by a special adjustment factor. And last, the MATLAB simulation results are shown, the broadband simulations and comparisons of performance are given.The performace of the above algorithms rely on the accuracy of the source location estimatimation; however, getting source location in strong interference background is not easy. A new method whithout the need of source information is presented and its frequency distortion is slighter. Simulation of the algorithm and comparisons of performance are given at the last.