Novel Joint Chip Sampling and Phase Synchronization Algorithm for Multistandard UMTS Systems

Youssef SERRESTOU, Kosai RAOOF, Joel LIENARD

GIPSA-LAB, CNRS UMR 5216, 961 Rue de Houille Blanche, 38402 St. Martin d' Heres, France.
GIPSA-LAB, CNRS UMR 5216, 961 Rue de Houille Blanche, 38402 St. Martin d’Hères, France.
LCIS-INPG, 50 Rue Barthélémy de Laffemas, 26902 cedex, Valence, France.

DOI: 10.4236/ijcns.2008.12014                

Abstract

CDMA Timing and phase offsets tracking remain as one of considerable factors that influence the performances of communication systems. Many algorithms are proposed to solve this problem. In general, these solutions process separately the chip sampling offset and phase rotation. In addition, most of proposed solutions can not assure a compromise between robustness criteria and low complexity for implementation in real time applications. In this paper we present an efficient algorithm for chip sampling and phase synchronization. This algorithm allows estimating and correcting jointly in real time, sampling instant and phase errors. The robustness and the low complexity of this algorithm are evaluated, firstly by simulation and then tested by real experimentation for UMTS standard. Simulation results show that the proposed algorithm provides very efficient compensation for sampling clock offset and phase rotation. A real time implementation is achieved, based on TigerSharc DSP, while using a complete UMTS transmission-reception chain. Experimental results show robustness in real conditions.

Keywords

Synchronization, DS-CDMA, UMTS, Joint Estimation, Early-late Loop, Phase Locked Loop

Conflicts of Interest

The authors declare no conflicts of interest.

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