Radar Is The Only Phase Launch Of Adaptive Digital Beamforming Technology Research

It is one of advanced technologies used in modern radar that applying adaptive algorithms to radiation pattern of an adaptive array in order to control nulls of the beam pattern and to suppress interferential signals.In order to make full use of the abilities of transmitting function modules, Phase-Only method is an optimal solution for radiation nulling. The most important feature of Phase-Only nulling method lies in only making use of phase perturbations for controlling pattern's nulls, namely, amplitude of weights is fixed. Phase-Only .nulling method is not only applied to reception pattern but also radiation pattern. However, this method only uses information of weights so that equations for defining phase perturbations are generally unlinear. Therefore, the analytical solution is more difficult. This paper goes into details on two practical Phase-Only algorithms including their theories, simulation results, and performance analyses in the third chapter. Both the two algorithms can be applied to adaptive arrays working on radiation mode, thus greatly improving radar "Four-Anti" capabilities.Before using Phase-Only algorithm to achieve nulling, estimations of the number of interferential sources and the DOA of interferential signals are needed. So, the spatial spectrum estimation basd on the Maximum Likelihood Method (Capon Method) and MUSIC algorithm used for detecting the number of interferential sources and the DOA of interferential signals are discussed in the second chapter. In addition, the paper introduces hardware structure of Digital Beam Form pilot system and software design based on algorithm mentioned above, also the experimental results are given in the fourth charpter of this thesis. Finally, a summary is given in the fifth chapter.