xwch_test.m是主测试文件；biaoji.mat存放滤波器系数；xiangweicha.m用FFT计算相位差。

仿真框架为：

1.标记信号和双音信号续接作为发送信号；

2.对双音中一个频率分量的相位做偏移，再经过一个低通滤波器（引入线性相位，模拟收发不能同步测量现象）后，作为收到的信号；

3.用一个检测信号对收发信号进行相关运算；

4.画出收发信号以及相关处理后的信号。找出相关信号的那个尖点，从而推算出收发双音信号0相位点；

5. 输入0相位点位置，计算相对相位差。-xwch_test.m is the main test file　biaoji.mat store filter coefficients　xiangweicha.m calculated using FFT phase difference. Simulation fr a mework: 1. Mark signals and then as a two-tone signal continued to send signals　2. On a two-tone frequency components of the phase shift to do, and then through a low pass filter (the introduction of linear phase, simulation can not simultaneously send and receive measuring the phenomenon), the as received signal　3. using a detection signal of the transceiver signal correlation operation　4. draw send and receive signals and related processed signal. Correlated signal of the cusp, which calculate the two-tone signal transceiver 0 phase point　5. Enter 0 phase point position, calculate the relative phase difference.