IRS辅助的无源双基地雷达联合波束赋形与反射优化

直接路径干扰由于路径损耗较小，其干扰强度远大于目标的反射回波，直接影响了无源双基地雷达的目标的探测性能。智能反射表面具有调控电磁波传播的能力，为此在雷达接收机附近放置智能反射表面，通过联合优化监视通道接收机波束赋形和无源智能反射表面的反射相位，可以将进入接收机的直接路径干扰功率约束在一定范围内，并且实现目标反射回波功率最大化，从而提高目标的检测性能。利用交替优化的方法，将联合优化问题转换为2个齐次和非齐次的二次约束二次规划问题，采用半定松弛方法和高斯随机化方法求解获得接收机波束赋形和智能反射表面的反射相位的最优解。仿真分析表明：利用了智能反射表面可以有效提高无源双站雷达在直接路径干扰下的探测性能。

Joint Beamforming and Reflect Optimization for IRS-Assisted PBR

Direct path interference, because of the small path loss, has a much greater interference intensity than the reflected echo of the target, which directly affects the detection performance of the passive bistatic radar target. Intelligent reflect surface (IRS) has the ability to control the propagation of electromagnetic waves. For this reason, an IRS is placed near the radar receiver. By optimizing the beamforming of the channel receiver and the reflected phase of the passive IRS, the direct path interference power entering the receiver can be constrained to a certain range, and the target echo power can be maximized, thus improving the target detection performance. The joint optimization problem is transformed into two homogeneous and non-homogeneous quadratically constrained quadratic programming problems by using alternating optimization method. The optimum solution for beamforming of receiver and reflective phase of IRS is obtained by using semi-definite relaxation method and Gaussian randomization method. Computer simulation analysis shows that the detection performance of passive bistatic radar under direct path interference can be effectively improved by using the IRS.