多站时差定位数字接收机设计

Design of digital receiver for multi⁃station TDOA location

针对多站时差定位接收系统探测精度和动态要求,文中设计一种基于确定性延迟的宽带接收机。硬件系统由基于GPS授时的确定性相位关系的时钟系统和宽带高速采集系统组成,实现300 MHz~18 GHz频段宽带信号的中频数字化接收和处理。同时,给出FPGA软件处理流程,采用信道化技术和数字视频检测技术实现对射频脉冲信号的截获和通道时间的测量。样机测试结果表明,接收机的最大瞬时带宽为200 MHz,瞬时动态超过66 dBc,综合动态大于78 dBc,延时随机误差小于100 ps,可满足多站时差定位接收系统的应用需求。

A wideband receiver based on deterministic delay is designed to meet the detection accuracy and dynamic requirements of multi⁃station TDOA positioning receiver system.The hardware system is composed of the deterministic phase relation clock system based on GPS time service and the broadband high⁃speed acquisition system,which can realize IF digitization reception and processing of 300 MHz~18 GHz broadband signals.FPGA software processing flow is given,and channelization technology and digital video detection technology are adopted to achieve the interception of RF pulse signal and channel time measurement.The prototype testing results show that the maximum instantaneous bandwidth of the receiver is 200 MHz,its instantaneous dynamic can exceed 66 dBc,its comprehensive dynamic can exceed 78 dBc,and its delay random error is less than 100 ps,which can meet the application requirements of the multi⁃station TDOA positioning receiver system.