DocumentCode :
1192501
Title :
Low complexity iterative detection for OFDMA uplink with frequency offsets
Author :
Ahmed, S. ; Zhang, Li
Author_Institution :
Leeds Univ., Leeds
Volume :
8
Issue :
3
fYear :
2009
fDate :
3/1/2009 12:00:00 AM
Firstpage :
1199
Lastpage :
1205
Abstract :
In this work, we propose an iterative algorithm for the detection of transmitted symbols at the uplink of an orthogonal frequency-division multiple access (OFDMA) system. The algorithm allows distinct frequency-offsets (FO)s from each user that cause multiple-access and self interference. The proposed algorithm squeezes the interference of subcarrier k into 2D + 1 nearby subcarriers by preprocessing the received signal and yields a banded structure interference matrix. Here, the value of D depends on the FO and determines the squeezing depth. The proposed algorithm exploits this banded structure and realizes a low complexity iterative soft-interference-cancellation minimum mean-squared error (SIC-MMSE) equalizer that can be used in Turbo equalization. Simulation results show that the bit-error-rate (BER) performance of the proposed algorithm outperforms existing detection algorithms and is very much close to the zero-FO frequency-domain-equalization (zero-FO-FDE).
Keywords :
OFDM modulation; equalisers; error statistics; frequency division multiple access; interference suppression; iterative methods; least mean squares methods; signal detection; bit-error-rate; frequency offsets; interference matrix; iterative detection; iterative soft-interference-cancellation; minimum mean-squared error equalisers; orthogonal frequency-division multiple access; self interference; signal processing; turbo equalization; Bit error rate; Computational complexity; Detection algorithms; Equalizers; Frequency synchronization; Iterative algorithms; Matrix decomposition; Multiple access interference; OFDM; Wireless communication; FOs synchronization; OFDMA uplink; iterative detection;
fLanguage :
English
Journal_Title :
Wireless Communications, IEEE Transactions on
Publisher :
ieee
ISSN :
1536-1276
Type :
jour
DOI :
10.1109/TWC.2009.080724
Filename :
4801471
Link To Document :
بازگشت