PLL Unwrapping Structures using Polynomial Prediction Algorithm for Noisy Carrier Phase Tracking

摘要

Since the rise of technologies using GNSS positioningsystems, development of carrier phase tracking receiverfor precise point positioning in hostile environments isbecoming one of the most important challenges for futuresatellite navigation applications. Because phase lockedloops (PLL) that track carrier phase suffer from cycleslips phenomenon, noise robustness of the formers has tobe reinforced if one wants to use precise positioningtechniques in the widest range of challengingenvironments.The purpose of this article is to propose a new PLL designusing a phase unwrapping algorithm that effectivelycorrects cycle slips due to phase noise in low CN0. Unlikephase unwrapping algorithms using a threshold approachfor cycle slips detection, the algorithm implemented inour PLL structure is based on a system of prediction andpre-compensation of the phase dynamic stress. In order toreduce the cycle slips and enforce noise robustness ofphase tracking, this algorithm is adapted to tracking loopswith the aim to propose two innovative PLL structures. Acomparative study is performed to show the effectivenessof the two proposed structures in case of noisyenvironment.