基于单比特采样的FMCW-MIMO载频捷变雷达目标参数估计

Target Parameter Estimation for FMCW-MIMO Carrier Frequency Agile Radar via One-bit Sampling

单比特采样技术可以有效降低雷达系统的复杂度、成本和功耗,但往往会带来性能上的损失。为此,提出一种基于单比特采样的调频连续波-多输入多输出(FMCW-MIMO)载频捷变雷达系统。该系统选择FMCW作为基带信号,并加入捷变载频,有效提高了雷达分辨率。同时通过随机切换发射天线的方式以降低发射机的功率。该系统的接收端采用单比特量化器,大大降低了系统复杂度。针对单比特量化信号,利用凸优化算法找出目标的粗分辨率距离门,对同一粗分辨率距离门中的目标进行距离、速度和角度3个维度的网格细分,构建单比特稀疏重构问题模型,利用二进制软阈值迭代算法估计出目标的距离、速度以及角度信息参数。实验结果表明,该系统在降低系统复杂度的同时依然能够保证较好的目标探测性能。

The one-bit sampling technology can effectively reduce the complexity,cost and power consumption of radar system,but it often results in performance loss.A Frequenay-Modulated Continuous-Wave-Multiple-Input Multiple-Output(FMCW-MIMO)carrier frequency agile radar system based on one-bit sampling is proposed,which uses FMCW waveforms as baseband signal,and applies agile carrier frequency to improve the radar resolution effectively.At the same time,the transmitter power is reduced by switching the transmission antenna randomly.The receiver of the system uses one-bit quantizers for signal acquisition,which greatly reduces the system complexity.For one-bit quantized signals,the coarse resolution range profile of the target is found by using the convex optimization algorithm,then the target in the same coarse resolution range profile is subdivided into three dimensions including range,velocity and angle.A one-bit sparse reconstruction problem model is built.Finally,the range,velocity and angle parameters of the target can be estimated using the binary soft threshold iteration algorithm.The experimental results show that the proposed system can largely reduce the system complexity while still providing good target estimation performance.