A mainlobe interference suppression system based on mismatched filtering

External interference is the major performance limiting factors of High frequency surface wave radar (HFSWR) for array signal processing. Especially when the interference falls into the main lobe, the beam pattern is distorted with conventional adaptive digital beam former for the sake of suppressing the main lobe interference. In this paper, a system for suppressing external interference is proposed. This system includes three processing modules. The first module receives the main array radar data and produces matched radar data while the second one receives the virtual auxiliary array radar data and produces mismatched radar data based on mismatch filtering. And the last one is an adaptive beam former based on the Coherent Side-lobe Cancellation (CSLC) algorithm which is connected with the former two modules. Effectiveness and practicality of this interference suppression system are confirmed by simulation data and real data processing results.