一种基于低成本软件无线电的二维测向系统设计

Design of a Two-dimensional Direction-finding System Based on Low-cost Software Defined Radio

为解决现有测向系统体积大、运算量高、成本高、同步采集困难等问题,设计了一种低成本高精度二维测向系统,由五阵元十字型天线阵列及HackRF One同步采集子系统组成。该测向系统通过外接频率源、引入时间同步信号以及初始相位校准分别实现了接收设备间频率同步、时间同步、相位同步,然后将同步的采集信号采用多重信号分类(Multiple Signal Classification,MUSIC)算法进行处理,估计出二维波达方向。实验结果表明,系统的同步误差可控制在一个采样周期内,定位误差小于2°,可广泛应用于雷达、声呐、室内定位等多种领域。

To address the shortcomings of existing direction-finding(DF)systems such as large size,high computational complexity,high cost,and difficulties in synchronous acquisition,a low-cost system is proposed for two-dimensional(2D)high-accuracy DF.The system consists of a five-element cross antenna array,a synchronous acquisition subsystem based on HackRF One,and a software defined radio.The five receiving paths are frequency,time and phase synchronization via a shared external frequency source,a shared time synchronization signal and initial phase calibration,respectively.Then the synchronized acquired signals are processed by Multiple Signal Classification(MUSIC)algorithm to estimate the 2D direction of arrival(DOA).Experimental results show that the synchronization error of the system can be controlled within one sampling period.With less than 2°estimation error,the low-cost system can be widely used in radar,sonar,indoor positioning and other fields.