Title :
Analysis of Decision-Feedback Based Broadband OFDM Systems
Author :
De Baynast, Alexandre ; Sabharwal, Ashutosh ; Aazhang, Behnaam
Author_Institution :
Dept. of Electr. & Comput. Eng., Rice Univ., Houston, TX
fDate :
Oct. 28 2005-Nov. 1 2005
Abstract :
In wireless communications, about 25% of the bandwidth is dedicated to training symbols for channel estimation. By using a semi-blind approach, the training sequence length can be reduced while improving performance. The principle is as follows: the detected symbols (hard decision) are fed back to the channel estimator in order to re-estimate the channel more accurately. However, semi-blind approach can significantly deteriorate the performance if the bit error rate is high. In this paper, we propose to determine analytically the minimum signal to noise ratio (SNR) from which a semi-blind method starts to outperform a training sequence based only system
Keywords :
OFDM modulation; automatic repeat request; broadband networks; channel estimation; error statistics; mobile radio; bit error rate; broadband OFDM systems; channel estimation; decision-feedback analysis; semiblind approach; signal to noise ratio; symbol detection; training sequence length; wireless communications; Additive noise; Bandwidth; Bit error rate; Channel estimation; Detectors; Fading; OFDM; Signal analysis; Signal to noise ratio; Wireless communication;
Conference_Titel :
Signals, Systems and Computers, 2005. Conference Record of the Thirty-Ninth Asilomar Conference on
Conference_Location :
Pacific Grove, CA
Print_ISBN :
1-4244-0131-3
DOI :
10.1109/ACSSC.2005.1599840
