High-speed multi-target detection with narrowband radar

High-speed multi-target detection is a challenging problem in radar applications. Typically, targets with high speed go through several range cells in the observation period, which makes it more difficult to obtain each target's power coherently accumulated for target detection. In this study, novel multi-target detection with a narrowband radar system is proposed. In order to remove range migration and obtain coherent integration of the target energy, the Keystone transform is applied to the moving targets. However, because of the high target velocity and the low radar pulse repetition frequency phase ambiguity will occur, so the range migration will not be corrected properly. Then the phase ambiguity function of the kth target is compensated, and the envelope of the kth target concentrates in a certain range cell. Following by frequency modulation rate search a quadratic phase term is compensated, and the signal energy is finally coherently accumulated by FT analysis. The target is detected if the ratio of peak value to noise is higher than a predetermined threshold. For target detection in low signal-to-noise ratio (SNR), the Clean technique is applied. The proposed algorithm is verified by simulation and raw radar data results.