Title :
Semiblind multichannel identification in asynchronous multiuser OFDM systems
Author :
Jung, Hyejung ; Zoltowski, Michael D.
Author_Institution :
Sch. of Electr. & Comput. Eng., Purdue Univ., West Lafayette, IN, USA
Abstract :
This paper presents a novel subspace-based semiblind channel identification scheme for asynchronous multiuser orthogonal frequency division multiplexing (OFDM) systems with antenna diversity. The inherent property of asynchronous OFDM signals allows separation of the desired user´s channel from the interfering users´ channels via subspace decomposition. Moreover, the proposed semiblind channel estimator overcomes practical limitations of the conventional subspace method due to unknown channel lengths and noise-corrupted data by employing pilot symbols. Simulation results demonstrate that the semiblind channel estimator significantly outperforms a pilot-only estimator when most part of the noise subspace is exploited.
Keywords :
OFDM modulation; channel estimation; diversity reception; eigenvalues and eigenfunctions; multiuser channels; OFDM; antenna diversity; asynchronous multiuser; channel estimator; noise-corrupted data; orthogonal frequency division multiplexing system; subspace decomposition; subspace-based semiblind channel identification scheme; Bandwidth; Channel estimation; Code division multiplexing; Eigenvalues and eigenfunctions; Multiaccess communication; OFDM; Receiving antennas; Signal to noise ratio; Telephony; Timing;
Conference_Titel :
Signals, Systems and Computers, 2004. Conference Record of the Thirty-Eighth Asilomar Conference on
Print_ISBN :
0-7803-8622-1
DOI :
10.1109/ACSSC.2004.1399223
