MIMO Radar Transmit Beampattern Design Without Synthesising the Covariance Matrix

摘要

Compared to phased-array, multiple-input multiple-output (MIMO) radars provide more degrees-offreedom(DOF) that can be exploited for improved spatial resolution, better parametric identifiability,lower side-lobe levels at the transmitter/receiver, and design variety of transmit beampatterns. Thedesign of the transmit beampattern generally requires the waveforms to have arbitrary auto- and crosscorrelationproperties. The generation of such waveforms is a two step complicated process. In thefirst step a waveform covariance matrix is synthesised, which is a constrained optimisation problem.In the second step, to realise this covariance matrix actual waveforms are designed, which is also aconstrained optimisation problem. Our proposed scheme converts this two step constrained optimisationproblem into a one step unconstrained optimisation problem. In the proposed scheme, in contrast tosynthesising the covariance matrix for the desired beampattern, nT independent finite-alphabet constantenvelopewaveforms are generated and pre-processed, with weight matrix W, before transmitting fromthe antennas. In this work, two weight matrices are proposed that can be easily optimised for the desiredsymmetric and non-symmetric beampatterns and guarantee equal average power transmission from eachantenna. Simulation results validate our claims.