D-BLAST OFDM with Channel Estimation

Autor: Du Jianxuan, Li Ye (Geoffrey)
Jazyk: angličtina
Rok vydání: 2004
Předmět:
Zdroj: EURASIP Journal on Advances in Signal Processing, Vol 2004, Iss 5, p 789540 (2004)
Druh dokumentu: article
ISSN: 1687-6172
1687-6180
DOI: 10.1155/S1110865704311054
Popis: Multiple-input and multiple-output (MIMO) systems formed by multiple transmit and receive antennas can improve performance and increase capacity of wireless communication systems. Diagonal Bell Laboratories Layered Space-Time (D-BLAST) structure offers a low-complexity solution for realizing the attractive capacity of MIMO systems. However, for broadband wireless communications, channel is frequency-selective and orthogonal frequency division multiplexing (OFDM) has to be used with MIMO techniques to reduce system complexity. In this paper, we investigate D-BLAST for MIMO-OFDM systems. We develop a layerwise channel estimation algorithm which is robust to channel variation by exploiting the characteristic of the D-BLAST structure. Further improvement is made by subspace tracking to considerably reduce the error floor. Simulation results show that the layerwise estimators require 1 dB less signal-to-noise ratio (SNR) than the traditional blockwise estimator for a word error rate (WER) of when Doppler frequency is 40 Hz. Among the layerwise estimators, the subspace-tracking estimator provides a 0.8 dB gain for WER with 200 Hz Doppler frequency compared with the DFT-based estimator.
Databáze: Directory of Open Access Journals
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