Abstract:

The signal-to-noise ratio(SNR) of small radar cross section(RCS) targets can be improved by coherent integration. But the maneuvering of targets causes range cell migration and Doppler cell migration. The reasons of above problems are analyzed from the two-dimensional(2-D) frequency domain, and based on this, a novel method of long term coherent integration is proposed. In fast frequency-slow time domain the Keystone transform is taken and the range cell migration is corrected, then a quadratic phase compensation function is multiplied and the objective function is constructed to search the acceleration in the compensation function. The characteristic of the new method is that the maximum value of the objective function equals to the coherent integration value, and this reduces the operational quantity and improves the operation speed. The simulation results verify the effectiveness of the proposed method.