Frequency diversity waveform with NLFM signals

In this paper, we propose a frequency coding waveform with a nonlinear frequency modulation (NLFM) signal for the multiple-input multiple-output (MIMO) radar. The transmitted signal of each transmitting antenna is a pulse train, of which, the sub-pulses are NLFM signals with different carrier frequencies. The frequency sequence and the parameter of the nonlinear frequency function are optimized to reduce the autocorrelation sidelobe and cross-correlation peaks. Compared to the existing frequency coding waveforms, the autocorrelation sidelobes and the cross-correlation level of the proposed waveform are improved significantly. In addition, with this new waveform, the ambiguity functions with sharp shape are achieved and the cross ambiguity functions have good Doppler tolerance.