Creating and sharing knowledge for telecommunications

Uplink channel estimation for multi-user OFDM-based systems

Ribeiro, C. ; Garcia, M. J. F.-G. ; Jiménez, V. P. G. ; Gameiro, A. ; Armada, A. G.

Wireless Personal Communications Vol. 47, Nº 1, pp. 125 - 136, October, 2008.

ISSN (print): 0929-6212
ISSN (online): 0929-6212

Journal Impact Factor: 0,653 (in 2014)

Digital Object Identifier: 10.1007/s11277-007-9396-7

Abstract
In this paper we propose a simple, yet flexible and efficient, channel estimator for the uplink in broadband orthogonal frequency division multiplexing (OFDM) systems. The processing is performed in the time-domain, by extracting the Channel’s Impulse Response (CIR) for each user from a joint training signal. In this OFDM system, the pilot sequence we advocate, where all users share the same pilot sub-carriers, consists of one OFDM-symbol endowed with time-shifted properties per user, which isolates each user’s CIR and is robust against multi-user interference. The feasibility of our approach is substantiated by system simulation results obtained using BRAN-A broadband mobile wireless channel model.