Fast transmit nulling method for 4D MIMO radar based on joint design of spatiality and temporality

In this paper, a fast transmit nulling method for 4D multiple-input multiple-output (MIMO) radar based on joint design of spatiality and temporality is proposed. The method adopts the problem decomposition strategy and the approximate optimization method to design a scheme for transmit weighting with common notch, for the spatial part of the transmit waveform, the proposed cost function can simultaneously take into account the information of the azimuth and elevation dimensions, and for the temporal part of the transmit waveform, a set of weighting coefficients on the allocation of the sub-pulse temporal width is designed by using the linear programming (LP) algorithm to be used for flexibly regulate the transmit beampattern of planar array, and finally generate the required multibeam transmit nulling beampattern according to the mission requirements of 4D MIMO radar in jamming environment. To further reduce the computational complexity of the proposed algorithm and make it better to achieve fast transmit under constant modulus constraint, the majorization-minimization (MM) algorithm is used to optimize the transmit weighting vectors of planar array, and the original problem is decomposed into several sub-problems to be solved at the same time. To further improve the convergence speed of the proposed algorithm, the existing accelerator SQUAREM is used as the solution of the problem. Simulation results show that the algorithm requires significantly less computing time for large-scale planar array compared to the existing algorithm.