DELAY ESTIMATION IN CDMA COMMUNICATIONS USING A FAST ICA ALGORITHM

R–azvan Cristescu 1 , Tapani Ristaniemi 2 , Jyrki Joutsensalo 3 , and Juha Karhunen 1
razvan@mail.cis.hut.fi, riesta@mit.jyu.fi, jyrkij@cs.tut.fi, Juha.Karhunen@hut.fi

In this paper, we propose a method for timing acqui­ sition in a code division multiple access (CDMA) com­ munications system. The assumptions made are that the data signals corresponding to different users are sta­ tistically independent, and that a minor pilot sequence corresponding to the desired user is available. An in­ dependent component analysis (ICA) approach based on a fast fixed­point algorithm is used for simultaneous demodulation of the symbol sequence and finding of synchronization information of the user of interest. No additional pilot signal is used for the timing acquisition. Our semi­blind method performs better than conven­ tional matched filter detector and CMOE receiver.