Joint Frequency- and PRF-Agile Waveform Design for Moving Target Detection With Efficient Coherent Accumulation

Frequency and pulse repetition frequency (PRF) agile waveform can improve the radar's anti-jamming capability and decrease the probability of signal interception in complex electromagnetic environments. However, agile frequency introduces jitter initial phases; agile PRF leads to the slow-time nonuniform sampling; these two problems couple with each other and lead to incoherent echo signals. Moreover, existing parametric and scale transform coherent processing methods reduce the signal-to-noise ratio (SNR) gain and increase the processing complexity. Aiming at these problems, we propose a joint frequency and PRF agile (JFPA) waveform design method for efficient coherent processing algorithm by fast Fourier transform (FFT). A JFPA waveform design method is presented to reduce coherent processing complexity by combining jitter initial phase compensation and coherent accumulation. In particular, the number of different frequencies is less compared to the pulse numbers in the JFPA waveform, which facilitates the implementation of the proposed phase cancellation method for co-frequency signals to compensate for the jittery initial phase. Furthermore, the JFPA waveform echo signal after jitter initial phase compensation is designed to be a coherent signal, so that the FFT algorithm can be employed to achieve coherent accumulation of the proposed waveform. Finally, the simulated data are used to verify the remarkable moving targets detection performance compared with the existing compensation and accumulation methods.