Autocorrelation Sidelobe Suppression in MIMO Radar OFD-LFM Waveforms

Aiming at the problem of high grating sidelobes in the autocorrelation function of orthogonal frequency-division linear frequency modulation (OFD-LFM) signals synthesized, this paper proposes a novel multiple-input-multiple-output (MIMO) radar OFD-LFM waveform design method, which aims to suppress the grating sidelobes of autocorrelation function effectively. First, the signal bandwidth of each sub-channel is the total bandwidth; second, each sub-channel transmit waveform of a MIMO radar is split into multiple subcarriers, and each subcarrier is assigned an unequal modulation bandwidth as well as an unequal timewidth. A genetic algorithm is used to determine the optimal solution by constructing a model designed to jointly optimize the subcarrier modulation bandwidth and subcarrier modulation time for each channel. Simulation results show that the emergence of the high grating sidelobes is effectively suppressed by jointly selecting the freedom of choice for optimizing the modulation bandwidth and modulation time of the transmit signal.