In this paper we consider the problem of data-aided synchronization in the up-link of a multiple access (MA) orthogonal frequency division multiplexing (OFDM) system based on offset quadrature amplitude modulation (OQAM). In particular, the joint maximum-likelihood (ML) phase offset, carrier-frequency offset (CFO) and symbol timing (ST) estimator,exploiting a short known preamble embedded in the burst received from each of U users in multipath channel, is considered. Under the assumption that the CFO of each user is sufficiently small, the considered approach leads to U different approximate ML (AML) estimators; moreover, delays, amplitudes and phase-offsets are jointly estimated for each path. Specifically, the phase, amplitude and CFO estimators are in closed form while the AML ST estimators require a one-dimensional maximization procedure. The performance of the proposed joint AML estimator is assessed via computer simulations both in AWGN and multipath channel.
Multipath-aware joint symbol timing and CFO estimation in multiuser OFDM/OQAM systems / Izzo, Luciano; Mattera, Davide; Tanda, Mario. - (2010), pp. 1120-1124. (Intervento presentato al convegno 18th European Signal Processing Conference (EUSIPCO 2010) tenutosi a Aalborg, Denmark nel August, 23-27, 2010).
Multipath-aware joint symbol timing and CFO estimation in multiuser OFDM/OQAM systems
IZZO, LUCIANO;MATTERA, DAVIDE;TANDA, MARIO
2010
Abstract
In this paper we consider the problem of data-aided synchronization in the up-link of a multiple access (MA) orthogonal frequency division multiplexing (OFDM) system based on offset quadrature amplitude modulation (OQAM). In particular, the joint maximum-likelihood (ML) phase offset, carrier-frequency offset (CFO) and symbol timing (ST) estimator,exploiting a short known preamble embedded in the burst received from each of U users in multipath channel, is considered. Under the assumption that the CFO of each user is sufficiently small, the considered approach leads to U different approximate ML (AML) estimators; moreover, delays, amplitudes and phase-offsets are jointly estimated for each path. Specifically, the phase, amplitude and CFO estimators are in closed form while the AML ST estimators require a one-dimensional maximization procedure. The performance of the proposed joint AML estimator is assessed via computer simulations both in AWGN and multipath channel.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.