Iterative channel estimation, detection, and decoding in large CDMA systems
2010 (English)In: 6th International Symposium on Turbo Codes and Iterative Information Processing, ISTC 2010, 2010, 16-23 p.Conference paper (Refereed)
The large system analysis of randomly spread direct-sequence code-division multiple-access systems operating over frequency-selective fading channels is considered. Iterative multiuser detection and decoding (MUDD) based on generalized posterior mean estimation and single-user sum-product decoding is assumed to be used at the receiver. The channel state information (CSI) at the MUDD is mismatched and obtained by a linear channel estimator whose initial decisions are iteratively refined with the help of information feedback provided by the MUDD. Furthermore, a new training method by means of probability-biased signaling is proposed. The results indicate that in the large system limit and under certain threshold loads, a near single-user performance with perfect CSI can be achieved using a vanishing training overhead. It is also found that for the considered setups, the iterative linear minimum mean square error based channel estimator is near optimal for relatively slowly time-varying multipath fading channels.
Place, publisher, year, edition, pages
2010. 16-23 p.
Telecommunications Signal Processing
IdentifiersURN: urn:nbn:se:kth:diva-78616DOI: 10.1109/ISTC.2010.5613863ScopusID: 2-s2.0-78649294570ISBN: 978-1-4244-6745-7OAI: oai:DiVA.org:kth-78616DiVA: diva2:492689
6th International Symposium on Turbo Codes and Iterative Information Processing, ISTC 2010. Brest. 6 September 2010 - 10 September 2010
QC 201202092012-02-082012-02-082012-02-09Bibliographically approved