该代码主要实现环路滤波器矩阵的设计，环路滤波器的功能主要是在鉴相器的输出端衰减高频误差分量，以提高抗干扰性能；在环路跳出锁定状态时，提高环路以短期存储，并迅速恢复信号。-The code mainly realizes the design of loop filter matrix, Loop filter function is mainly in the output of the phase discriminator attenuation of high frequency error component, in order to improve the anti-jamming ability　In loop lock state, improve the loop with short-term storage, and quickly return signal.