Space-time adaptive processing airborne radar with coprime pulse repetition interval

In this paper, motivated by the success of coprime array in the direction-of-arrival (DOA) estimation, we introduce the idea of coprime pulse repetition interval (PRI) into the space-time adaptive processing (STAP) airborne radar. Through transmitting and receiving the pulses with coprime PRI, we can reduce the transmitting energy and improve the capabilities of electronic counter-countermeasures (ECCM). We use the lags between the receiving pulses to construct virtual pulses. By using the virtual pulses, we can obtain a new snapshot with a larger dimension than the real one. The constructed snapshots are exploited to estimate the clutter-plus-noise covariance matrix and then to form the STAP filter. Simulation results show that the proposed coprime PRI strategy STAP radar can achieve a good performance with reduced pulses.