摘要
动平台分布式雷达系统可有效提升系统的生存能力和探测性能,但运动平台之间通常采用无线传输方式,难以配备大通信带宽以传输完整的信号数据,给雷达系统的高性能检测带来极大挑战。由于低比特量化技术可显著降低分布式系统的通信传输代价和计算资源消耗,该文针对低信噪比弱信号环境下提出了动平台分布式雷达系统的低比特量化运动目标检测算法。首先,根据系统资源将各节点的多脉冲观测数据选择对应位数的低比特量化器进行量化,推导了关于量化器和多个目标状态的似然函数。其次,证明了低比特量化数据对应似然函数关于未知目标反射系数的凸性,并基于该特性设计了多普勒频移和反射系数的联合估计器。然后,针对探测区域中存在的多个状态未知目标设计了多目标检测器,推导了其恒虚警率门限。最后,通过推导系统的渐近性能设计了最优低比特量化器,在保证系统鲁棒性的同时有效提升了系统的检测性能。仿真实验分析了所提算法的检测与估计性能,结果证明了所提算法在低信噪比弱信号环境下的有效性,同时表明低比特量化数据可在仅占用低于20%通信带宽的基础上实现接近高精度(16比特量化)数据对应的检测和估计性能,且2比特量化策略可作为检测性能和雷达系统资源消耗的折中选择。
Distributed radar with moving platforms can enhance the survivability and detection performance of a system,however,it is difficult to equip these platforms with sufficient communication bandwidth to transmit high-precision observed data,posing a great challenge to the high-performance detection of a distributed radar system.Because low-bit quantization can effectively reduce the computation cost and resource consumption of distributed radar systems,in this paper,we investigate the high-performance detection of multiple moving targets using the distributed radar system on moving platforms by adopting the low-bit quantization strategy.First,according to system resources,multipulse observed data of each node may be quantized with a low-bit quantizer and the likelihood function relative to the quantizer and states of multiple targets are derived.Subsequently,based on the convexity of the likelihood function relative to the unknown reflection coefficients,a joint estimation algorithm is designed for the Doppler shifts and reflection coefficients.Then,a generalized likelihood ratio test based multi-target detector is designed for detecting multiple targets in the surveillance area with unknown states,and deriving the constant false alarm rate detection threshold.Finally,the optimal low-bit quantizer is designed by deriving the asymptotic detection performance of the system,which effectively improves the detection performance and ensures robustness.Simulation experiments are conducted to analyze the detection and estimation performance of the proposed algorithm,thereby demonstrating the effectiveness of the proposed algorithm for weak signals,and showing that the low-bit quantized data can achieve detection and estimation performance close to that of the high-precision(16-bit quantization)data while consuming a complementary 20%of the communication bandwidth.Besides,according to the simulated results,the two-bit quantization strategy may be a trade-off between the detection performance and resource consumption of the distributed radar system.
作者
杨诗兴
张国鑫
梁雲飞
易伟
孔令讲
YANG Shixing;ZHANG Guoxin;LIANG Yunfei;YI Wei;KONG Lingjiang(School of Information and Communication Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China)
出处
《雷达学报（中英文）》
EI
CSCD
北大核心
2024年第3期584-600,共17页
Journal of Radars
基金
国家自然科学基金(62231008,U19B2017)
中央高校基本科研业务费专项资金(ZYGX2020ZB029)。
关键词
分布式雷达系统
运动平台
目标检测
低比特量化
最优量化器
Distributed radar systems
Moving platforms
Targets detection
Low-bit quantization
Optimal quantizer
