DocumentCode :
1605026
Title :
Adaptive diversity combination of space-time block coding in OFDM-CDMA systems with pilot-based channel estimation
Author :
Feng, Aigang ; Yin, Qinye ; Zhang, Jianguo ; Lin, Yonghua
Author_Institution :
Inst. of Inf. Eng., Xi´´an Jiaotong Univ., China
Volume :
1
fYear :
2002
fDate :
6/24/1905 12:00:00 AM
Firstpage :
190
Abstract :
We investigate the transmit diversity for orthogonal frequency division multiplexing code division multiple access (OFDM-CDMA). Diversity transmission at the base station is an effective technique to combat channel fading. Space-time (ST) coding has been proposed as coding technique to improve the system performance with additional gains. By combing the spatial transmit diversity with the space-time codes for OFDM systems it shows high performance improvement. But it is important to remark that ST decoding requires multichannel state information at the receiver. Thus the achievable diversity gain comes at the price of proportional increase in the amount of training or computation complexity, which incurs efficiency loss especially in a rapidly varying environment. In an OFDM system, there exist pilots used for frame detection, carrier frequency offset estimation and channel estimation. We proposed a receive scheme, which use the pilot structure to estimate the multichannel state information and use the CMA-based channel tracking in the space-time coded transmit diversity OFDM-CDMA systems. Numerical simulations illustrate the effectiveness of this algorithm.
Keywords :
OFDM modulation; block codes; code division multiple access; decoding; diversity reception; mobile radio; multipath channels; multiuser channels; parameter estimation; receiving antennas; transceivers; transmitting antennas; CMA-based channel tracking; OFDM-CDMA systems; ST decoding; adaptive diversity combination; base station; carrier frequency offset estimation; channel estimation; channel fading; code division multiple access; computation complexity; diversity gain; diversity transmission; frame detection; mobile communication systems; multichannel state information; multipath propagation; numerical simulations; orthogonal frequency division multiplexing; pilot structure; pilot-based channel estimation; receive antenna transceiver structure; space-time block coding; space-time coded transmit diversity; space-time codes; spatial transmit diversity; system performance; transmit antennas; Base stations; Block codes; Channel estimation; Fading; Frequency estimation; Multiaccess communication; OFDM; Performance gain; Space time codes; System performance;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Vehicular Technology Conference, 2002. VTC Spring 2002. IEEE 55th
Print_ISBN :
0-7803-7484-3
Type :
conf
DOI :
10.1109/VTC.2002.1002690
Filename :
1002690
Link To Document :
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