MIMO radar waveform design for transmit beampattern synthesis

Abstract

In this paper, the waveform design for transmit beampattern synthesis is studied in MIMO radar systems with colocated antennas. The waveform transmitted at each antenna is defined as a weighted sum of a set of discrete prolate spheroidal (DPS) sequences which have good orthogonal and band-limited properties. Assume that different transmit antennas use the same set of DPS sequences, while the weighting factors are variable which allows the correlation between different waveforms to be flexible and varied with the weighting factors. Optimum waveforms are designed to achieve a desired transmit beampattern under the constraint of a fixed total transmit energy. Unlike a traditional process, in which the waveform covariance matrix is designed in the first step and then the optimal waveforms are synthesised in the second step based on the designed waveform covariance matrix, it is shown in this work that the waveforms constructed by the DPS sequences need only one step to design the optimum waveforms. In this paper, we propose a new waveform design method for transmit beampattern synthesis which can efficiently match a desired transmit beampattern and control the power distributed at each beam in beampattern simultaneously. The choice of the number of the DPS sequences is also analyzed. Numerical simulations are provided to compare the performance of proposed method with that of the traditional methods.