Title :
An Improved Adaptive Receiver for OFDM Systems Using Conjugate Transmission
Author :
Wang, Chin-Liang ; Shen, Po-Chung ; Huang, Jia-Hong
Author_Institution :
Dept. of Electr. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan
Abstract :
In this paper, we propose an improved adaptive receiver in order to overcome the performance degradation problem encountered by the existing conjugate transmission schemes due to a time-varying frequency offset. We apply two different phase rotations on the two receiving paths instead of employing only one common phase rotation for both paths in the previous work. The two phase rotations are chosen properly based on the derived optimization results, such that an additional phase distortion on the detected symbol could be completely removed. For practical use, the block least mean-squared algorithm is applied to adaptively update the two phase rotations with the frequency offset variation. Computer simulation results show that the proposed scheme outperforms the existing works in terms of bit error rate performance, especially when a rapid frequency offset variation is considered.
Keywords :
OFDM modulation; error statistics; least mean squares methods; multiplexing; radio receivers; OFDM systems; adaptive receiver; bit error rate; computer simulation; conjugate transmission; least mean-squared algorithm; phase rotation; time-varying frequency offset; Bit error rate; Frequency estimation; Frequency modulation; OFDM; Optimized production technology; Receivers; Time frequency analysis;
Conference_Titel :
Vehicular Technology Conference (VTC Spring), 2011 IEEE 73rd
Conference_Location :
Yokohama
Print_ISBN :
978-1-4244-8332-7
DOI :
10.1109/VETECS.2011.5956696