双基地多载频MIMO雷达的直达波时间同步方法研究

摘要

建立了双基地多载频MIMO雷达的直达波信号模型并分析其特点，参考AM电路解调中常用的峰值包络检波电路，提出了一种新的二值包络检波法，该方法根据适当的门限和充放电时间将信号包络归一化为0，1两个值，以此来检测脉冲信号的上升沿和包络；对滑窗积累法进行循环扩展使其适用于脉宽较宽的准FMCW情况；针对信噪比很低的情况，提出了采用相关检测法来提取时间同步信号；最后对三种方法的运算量和性能进行了比较分析。%The direct-path wave signal model of bistatic multi-carrier-frequency （MCF） MIMO radar is constructed and its characteristics are analyzed. A novel binary envelope detection method is proposed using the envelope detection circuit in AM demodulation as reference. This method normalizes the signal envelope to two value, 0 or 1, to detect the rising edge and envelope. The slipping window accumulation method is circularly extended to be suit for the FMCW pulse signal with wide pulse-width. The correlative detection method is proposed to obtain the time synchronization in case of low signal to noise ratio （SNR）. Finally the computational complexity and performance of the three methods are analyzed and compared.