Blind Synchronization for Multi-rate DS-CDMA Systems Blind Synchronization for Multi-rate DS-CDMA Systemsy
نویسندگان
چکیده
Blind Synchronization for Multi-rate DS-CDMA Systemsy Zhouyue Pi and Urbashi Mitra Department of Electrical Engineering The Ohio State University, Columbus, OH 43210 e-mail:fpiz,[email protected] Abstract The synchronization problem of multi-rate asynchronous DS-CDMA systems is investigated. Both subspace and non-parametric methods are considered for two types of multi-rate access schemes, multi-code (MC) access and variable-spreading-length (VSL) access. An improved projection of signal vectors onto the noise subspace based on maximum likelihood methods is proposed. A two-stage estimation-detection strategy is developed for the VSL case which o ers strong performance with reduced complexity compared to traditional subspace methods.
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