Multipath Effects on the Performance of DLL in a GNSS Receiver

In order to improve the performance of a GNSS (Global navigation satellite system) receiver, multipath effects on common DLLs (Delay locked loops) are approached through comparisons with one coherent and three noncoherent DLLs under non-fading and fading conditions. The characteristics of multipath errors in DLL discriminators are analyzed and evaluated. Furthermore, the performance of DLL in the multipath fading environment is investigated and the methods to reduce multipath errors are derived. Finally, the method to select a proper DLL for a specialized multipath environment is provided which is helpful to design a high performance GNSS receiver.