扩展卡尔曼滤波估计载波参数的算法研究

提出了一种在接收信号幅度未知的情况下进行载波参数估计的扩展卡尔曼滤波算法，该算法把信号幅度及伪码自相关的乘积作为一个独立变量和载波相位、频率一起组成状态向量进行扩展卡尔曼滤波。理论分析表明该算法本质上是具有可变增益的幅度锁定环和相位锁定环的联合估计，并给出了稳态时环路闭环传输函数和等效噪声带宽的解析表达式。仿真结果表明该算法在高低信噪比下，均具有较高的估计精度和较快的收敛速度。

Estimation for Carrier Parameters Based on the Extended Kalman Filter

A method for estimating carrier parameters is proposed by using extended Kalman filter (EKF) when the amplitude of the received signal is unknown. In the method, the state vector of EKF is composed of the carrier phase, the frequency and the product of the signal amplitude and auto-correlation of PN code. Theoretical analysis illustrates that the method is essentially the joint estimation of amplitude-locked loop and phase-locked loop with variable gains. The closed-form expression of transform function and equivalent noise bandwidth are obtained. Numerical simulation shows that the method proposed can obtain the high accuracy of estimation and the short convergent time.