高分辨步进频雷达回波信号模拟方法设计及实现

Design and implementation of simulation method for echo signal from high-resolution frequency stepped radar

调频步进雷达信号作为一种距离高分辨信号广泛应用于各种新体制雷达中。在分析步进频回波信号数学模型的基础上,提出了一种基于FPGA并行理论和高速DAC架构的三阶DDS步进频回波模拟方法。实现方法保证了回波相位的线性特性,较真实地模拟雷达探测过程对信号的调制。实现方法采用三阶DDS嵌套的方式,对回波信号数学模型按CPI帧周期维度、PRT脉冲重复周期维度进行特征分解,完成回波信号数学模型到FPGA底层单元的映射。实测结果表明,该方法满足步进频信号处理中的相参性,较真实地实现了步进频回波模拟,为雷达引信系统算法测试提供便捷。

As a high-resolution range signal,the frequency modulation stepped radar signal is widely used in various new radar systems. Based on the analysis of step frequency echo signal mathematical model,a frequency stepped radar echo signal simulation method based on third-order DDS of FPGA parallel theory and high-speed DAC frameworks was designed and implemented. The method can ensure the linear characteristic of echo phase,and truthfully reflect radar signal modulation process. Three-order DDS nested mode is adopted in the method. Experimental results show that this method can satisfy the coherent nature of step frequency signal processing,and more truly realize step frequency echo simulation. It provided a convenient method for the algorithm testing of radar fuze system.