DocumentCode :
3625119
Title :
EM-Based MAP Channel Estimation and Data Detection for Downlink MC-CDMA Systems
Author :
Hakan Dogan;Erdal Panayirci;Hakan A. Cirpan
Author_Institution :
Dept. of Electr. & Electron. Eng., Istanbul Univ.
fYear :
2007
fDate :
3/1/2007 12:00:00 AM
Firstpage :
227
Lastpage :
231
Abstract :
In this work, we propose a joint MAP channel estimation and data detection technique based on the expectation maximization (EM) method with parallel interference cancelation (PIC) for downlink multi-carrier (MC) code division multiple access (CDMA) systems in the presence of frequency selective channels. The EM algorithm derived estimates the complex channel parameters of each subcarriers iteratively and generates the soft information representing the data a posterior probabilities. The soft information is then employed in a PIC module to detect the symbols efficiently. Moreover, the MAP-EM approach considers the channel variations as random processes and applies the Karhunen-Loeve (KL) orthogonal series expansion. The performance of the proposed approach are studied in terms of bit-error rate (BER) and mean square error (MSE). Throughout the simulations, extensive comparisons with previous works in literature are performed, showing that the new scheme can offer superior performance.
Keywords :
"Channel estimation","Downlink","Multicarrier code division multiple access","Multiaccess communication","Bit error rate","Interference cancellation","Frequency conversion","Frequency estimation","Iterative algorithms","Random processes"
Publisher :
ieee
Conference_Titel :
Wireless Communications and Networking Conference, 2007.WCNC 2007. IEEE
ISSN :
1525-3511
Print_ISBN :
1-4244-0658-7
Type :
conf
DOI :
10.1109/WCNC.2007.48
Filename :
4224293
Link To Document :
بازگشت