Performance analysis on MIMO radar waveform based on mutual information and minimum mean-square error estimation

Abstract

Section 3 the waveform optimization method based on MI and MMSE is presented in detail. In Section 4 the detection performance of the optimized signal is analysed. In Section 5 the simulation results are shown to illustrate the theory. The conclusions are given in Section 6.(4)s Yi(k)== Eaila 1 k +ni(k) 1=1 Define Y i =[Yi(l)"··'Yi(N)]T , A=[al' ... ,a s ] ,a i = [a i1,.··,aiS ]T , then we have Yj ==Aaj +nj In which p(t) == {1/.JTpO:::: t:::: T p , a j = [ail'" "",a jN t is o others the ith transmitter's space-time code, N denotes the code length. Generally we have N > s . As it is shown in Fig.1, The baseband signal received by ith antennas is s Nwhere T is the time delay, ail are complex numbers accounting for both the target backscattering and the channel propagation effects between the lth transmitter and the ith receiver, n i (t), i =1,... , rare zero-mean spatially uncorrelated, complex Gaussian random processes which include the external disturbance and the internal noises.The received signal is filtered by p * ( -t) and the output is sampled at the time instants T +(k -1) T p , the kth sample is denoted as Consider a MIMO radar model including s transmitters and r receivers. Let each transmitter emits a waveform concluding N continuous subpulses, which has a period of T p • The baseband signal of Xi (t) transmitted by ith antenna is given by Abstract Keywords: MIMO radar, MI, MSE, Detection PerformanceMultiple-Input Multiple-Output (MIMO) technology can improve the performance of radar by spatial diversity. Two methods for designing MIMO radar waveform are introduced in this paper. The first one is to design waveforms that maximize the conditional mutual information (MI) between the reflected waveform and the channel impulse response. The second one is to minimize the minimum mean-square error (MMSE) in channels estimation. A particular analysis of detection performance is made here to illuminate the improvement. Finally the simulation results are presented and the performances of the two approaches are compared.