Research On Pattern Synthesis And Adaptive Beamforming Of The Conformal Array

Based on the outstanding performance of the conformal array comparing withtraditional arrays, the conformal array has a very broad application prospect in airborneand spaceborne onboard occasions. In this paper, we do extensive and in-depth analysisand research against pattern synthesis and adaptive beamforming of the conformal array.we study several algorithms and do a lot of simulation to solve the problem about howto reduce the sidelobes and inhibit cross-polarization of the array pattern, how to obtainrobust beamformer under the bad circumstances of low number of snapshots and DOAangle mismatch model. The specific work can be summarized as follows:1. The mathematical model of the conformal array is built. The mathematicalmodel of the conformal array receiving data snapshot，conformal array polarizationoriented vector and the array element are described. We also introduced the steps aboutobtaining the array pattern by using the Euler rotation matrix.2. The airspace block diagram of the filter and spatial filtering theory isintroduced. We analyse three kinds of beam optimization criteria and briefly introducethree equivalent descriptions of the Capon beamforming: the spatial filtering Caponbeamforming, the generalized sidelobe canceller Capon beamforming and covariancefitting Capon beamforming. Finally, the performance of the Capon beamforming isanalyzed under the uniform linear array.3. The thesis studies an adaptive pattern synthesis algorithm to obtain lowsidelobe. Another algorithm, namely Alternating Projection, to inhibit thecross-polarization, is studied also. Finally, we do large number of simulation, whichshows the effectiveness of the two pattern synthesis algorithms.4. We study two robust Capon beamforming algorithms under the DOAadaptation model: the RCB of maximize the worst case and the RCB of thenon-degenerate elliptic constraints. Considering the DOA angle adapter, we do ellipticconstraint to the signal steering vector. The algorithms are simulated under thecylindrical array, showing that the algorithms are robust.