PN码相位精确测量的累加最小二乘法

利用最小二乘（LS）法可以实现PN码相位的精确测量，但该方法对粗同步要求高，难以满足实际工程需求。给出了一种新的累加LS法的实现结构，在该结构下根据鉴相曲线的波形变化特征，利用累加后的离散鉴相曲线的最大值和最小值点作为特征基准点，取最值之间的数据进行LS线性拟合，实现粗同步于半个码元宽度以内的伪码相位精确测量。理论分析表明，该方法的鉴相特性呈线性特征，可以有效使用累加LS线性拟合方法。仿真结果表明，该方法相比于其他方法使用范围更广，测量精度更高。

Precise measurement of PN code phase by accumulative least square method

As least square (LS) method, which is applied to precise measurement of PN sequence phase in high-accuracy, is limited in narrow range condition of coarse synchronization, it is difficult to satisfy the needs of practical project. A novel realized structure of accumulative LS method for PN sequence phase measurement is presented. According to the characteristic of phase discrimination curve, the accumulative maximal value and minimal value of the phase discrimination curve are viewed as the characteristic reference position, and the samples between the maximal value and the minimal value are fitted by LS method. A high-accuracy measurement of the PN sequence phase can be achieved in half-width of the chips under the condition of coarse synchronization. It is proved that the characteristic of phase discrimination is linear in theory, and can use accumulative LS method suitably. The simulation results indicate that the proposed method has wider range of coarse synchronization and higher measurement precision.