Piecewise adaptive beamfoming method with multiple constraints for OTHR

The coherent processing interval in Over-The-Horizon Radar (OTHR) is usually set long to strengthen the weak signals, which increases the nonstationarity of the inference and make it more difficult to be restrained. In this paper, a piecewise beamforming method using multiple constraints to hold the coherence of the clutter is proposed. Comparing with the existing method with one constraint, this method can restrain the non-stationary inference and avoid the spreading of the clutter in more complicated situation. Simulation results illustrate the efficiency of the method.