Waveform Design For Dual-Function MIMO Radar Communication System

In recent years,dual-function MIMO radar and communication systems as a way to solve the problem of an increasingly crowded radio spectrum have become a hot topic of research.In this thesis,the transmit waveform design of dual-function MIMO radar communication system is deeply studied,and how to design the integrated transmit waveform that can meet the requirements of both radar and communication under the same hardware platform is analyzed.The main work and innovation achievements are as follows:1.Focus on the transmit waveform design for dual-function MIMO radar communication systems under power constraints and constant mode constraints,an optimization method based on manifold framework is proposed.Firstly,the optimization problems under two non-convex constraints are transformed into unconstrained optimization problems in manifolds.Specifically,the gradient descent algorithm based on Riemannian complex hyperspherical manifolds proposed for power constraints has faster convergence characteristics than the traditional SDR algorithm,and the alternate optimization algorithm based on Riemannian complex circular manifolds proposed for constant mode constraints can obtain better radar and communication performance while ensuring constant-mode waveforms.2.The joint optimization of the transmit waveform for RIS-aided dual-function MIMO radar communication systems and RIS phase shift matrix is investigated.RIS has received considerable attention due to its potential in mitigating MUI,this thesis considers deploying intelligent reflector near dual-function radar communication systems to alleviate multi-user interference in the dual-function radar communication systems.Due to the high complexity of traditional methods to optimize the phase constraints of intelligent reflector,an alternate optimization method based on the Riemannian secondorder trust algorithm was proposed to transform the phase constraints of intelligent reflector into unconstrained solutions in manifold space.The simulation results show that the intelligent reflector can effectively improve the performance of the dual-function radar communication system.In addition,the proposed algorithm has faster convergence rate.3.In this section,the problem of joint transmit waveform and receive filter design for dual-function MIMO radar-communication systems is studied.In order to minimize the communication multi-user interference and ensure the radar target detection performance,the radar output signal-to-noise ratio criterion is used as the radar terminal design criterion in this thesis.In addition,the weight factor is introduced to realize the flexible trade-off between radar and communication performance.For the multi-variable optimization of the constant modulus constraint of the transmit waveform and the filter weight vector,the alternating optimization method is used to alternately optimize each variable to ensure the radar output SINR performance.Simulation results show that the proposed optimization framework and algorithm can not only achieve the flexible tradeoff between radar and communication but also ensure the radar detection performance while suppressing interference.