Multi-source pulse coherent accumulation method for distributed aperture coherent radar

Distributed coherent radar accomplishes target detection and tracking cooperatively through different units. The signal level coherent fusion of target echo requires high precision of coherent signal. The performance of coherent fusion is seriously affected by the time phase synchronization error between elements, the estimation error of coherent parameters, the range and Doppler migration caused by high maneuvering target and other factors. Aiming at the moving problem of high maneuvering target during coherent accumulation, the range and Doppler compensation are carried out by combining second-order keystone transform and dechirp. In the range compensation, the range migration of first-order term is compensated together by velocity ambiguity resolution after second-order transform, avoiding more velocity searches. In the Doppler compensation, cyclic autocorrelation function is used to reduce the computation amount of searching acceleration. Then the three dimensional target information of range, velocity and acceleration can be obtained and the target detection can be realized. Finally, the algorithm is verified by simulation.