GPS中使用扩展卡尔曼滤波器改进的延迟锁定环

延迟锁定环是GPS接收机中实现PN码的捕获和跟踪的重要部分，对系统的性能有着重要的影响。该文首先讨论了经典的延迟锁定环的组成和原理，接着介绍了卡尔曼滤波器以及为了应用于非线性系统的扩展卡尔曼滤波器，最后提出了用扩展的卡尔曼滤波器对传统的延迟锁定环的改进。

Use of the Extended Kalman Filter to Improve the Delay Locked Loop IN GPS

The delay-locked loop is important for the acquisition and tracking of the PN code and therefore has a great effect on the performance of the system. This paper first introduces the composition and operation principle of the typical DLL and then covers the Kalman Filter and the Extended Kalman Filter applied in the nonlinear system. It finally introduces the improvement of the typical DLL by using the Extended Kalman Filter.