Null Broadening and Sidelobe Control Method Based on Multi-parametric Quadratic Programming

The direction-of-arrival of jammer can be aimed at automatically based on the adaptive beamforming algorithm.However,it will be resulted in the mismatch between adaptive weight and data due to the perturbation of the interference location.Besides,the traditional beamformers may have unacceptably high sidelobes when few samples are available.To solve the above problems,an effective approach was presented to broaden null and control sidelobes.Firstly,a tapered covariance matrix was constructed to modify the measured covariance matrix.Secondly,multiple quadratic inequality constraints outside the mainlobe beampattern area were used to control sidelobes.Thirdly,the resulting optimization problem was formulated as a multi-parametric quadratic programming (mp-QP) problem.Simulation results were presented to verify the efficiency of the proposed algorithm,such as it can achieve higher array gain and the optimal weight vector can be easily obtained by real-valued computation.