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The calculation of sureface clutter power spectrum for PD radar

In the research of surface(terrain/sea) clutter calculation, the range-doppler model is employed universally since 1960s, but there are some problems in this method: the complexity of calculation in grid areas, no relationship with antenna pattern and the lack of results in nose-up conditions. In this article, a new self-adapting mesh generation method is presented in surface clutter calculation. In this method, after a rough equi-range-azimuth model used for preliminary mesh generation, the the mesh density will be increased depending on the nonuniformity of pattern gain and backscattering coefficient on the ground. The experimental mean, standard deviation of backscattering coefficients and clutter distribution models are employed to increase the authenticity of the simulation. The result infers that this method is credible and applicable to nose-up, nose-down attitudes and HPRF, MPRF modes.