RESEARCH ON DLL DISCRIMINATOR OF GPS SOFTWARE RECEIVER
Sun Fuyu 1) ; Zhang Peng 1,2) ; Xu Yaming 1,2) ; and Shen Zhijuan 1)
1)School of Geodesy and Geomatics, Wuhan University. Wuhan 430079;2) The Key Laboratory of Precise Engineering and Industry Surveying, State Bureau of Surveying and Mapping, Wuhan 430079
Abstract：The tracking performances of three discriminator functions based on Delay Lock Loop (DLL) were studied: Early Minus Late Power (EML Power), Early Minus Late Envelope (EML Envelope) and Dot Power (DOT). A new mode that shifting discriminator function based on the tracking state is proposed to improve the performance of tracking loop. The experimental results tested by actual IF data show modified discriminator tracking signal effectively.
