An application of systolic spatial processing technique in adaptive beamforming

Abstract

The adaptive beamformer applied in underwater acoustics, radar, or sonar, etc. must be able to achieve real-time signal processing and to overcome a variety of adverse environmental factors, such as coherent interference and pointing error, which often result in serious degradation of the array performance. Coherent interference is generally caused by multipath transmission or active jammer. On the other hand, pointing error is caused by an error in target signal direction estimation. Along with the advancement of very large-scale integration technologies, some of the common algorithms of signal processing are now implemented in highly pipelined and regular systolic arrays. This paper, adopting a QR systolic array as the computational engine and using the generalized sidelobe canceller (GSC) adaptive beamformer as the underlying architecture featuring a simple hard preprocessor, advances the systolic spatial processing technique (SSPT) to suppress effectively coherent interference and to improve the influence caused by pointing error. SSPT converges speedily and needs only a limited amount of sampling data to achieve adaptive processing. The computer simulations prove that the performance of SSPT is satisfactory.