一、引言准确画分参数的捕捉区域,对设计锁相环路是十分必须的。由于环路方程是非线性的,所以一般都不能准确解出,而必须采用各种近似方法给出捕捉曲线。关于线性,三角波,余弦鉴相,已经有一些文章提出了近似结果,本文对具有(1+K)sinφ/1+Kcosφ鉴相特性,RC积分滤波的锁相环路提出一个近似的捕捉曲线近似公式,以期得到实践的验证,并进一步改进。二、方程形式及参数选取考虑固定频率及相位输入的锁相环路方程 I. INTRODUCTION Accurate drawing parameters capture area, the design of the PLL is very necessary. Since the loop equations are non-linear, they are generally not accurately solved, and various approximations must be made to capture the curve. For linear, triangular and cosine phase discrimination, some results have been proposed in this paper. In this paper, we give an approximate approximation for the phase-locked loop with (1 + K) sinφ / 1 + Kcosφ phase discrimination and RC integration filtering Formula, in order to obtain the verification of practice, and further improve. Second, the equation form and parameter selection Consider the fixed-frequency and phase input phase-locked loop equations