Title :
Fast Time-Varying Channel Estimation for OFDM Systems With Narrowband Interference
Author :
Zaarour, Farah ; Simon, Eric Pierre
Author_Institution :
Inst. of Electron. Microelectron. & Nanotechnol. (IEMN) Lab., Univ. of Lille, Villeneuve d´Ascq, France
Abstract :
The problem of channel estimation in OFDM with narrowband interference (NBI) has been only investigated for slow time-varying channels. For the first time, a novel estimation framework is proposed for fast time-varying channels. The noise variances and channel are jointly estimated via the maximum a posteriori (MAP) expectation maximization (EM) algorithm. By considering in the EM formulation the channel as the unwanted parameter and the noise variances as the parameters to be estimated, a closed-form analytical expression for the estimation of the noise variances is obtained; the channel being given by the Kalman smoother. Mean square error (MSE) and bit error rate (BER) simulations confirm the effectiveness and robustness of the approach against mobility and its adequacy for practical interference scenarios.
Keywords :
OFDM modulation; channel estimation; error statistics; expectation-maximisation algorithm; interference (signal); mean square error methods; time-varying channels; BER; EM algorithm; Kalman smoother; MAP; MSE; NBI; OFDM system; bit error rate; closed-form analytical expression; expectation maximization algorithm; fast time-varying channel estimation; maximum a posteriori; mean square error; narrowband interference; noise variance; orthogonal frequency division multiplexing; Channel estimation; Estimation; Kalman filters; Mathematical model; OFDM; Signal to noise ratio; Channel Estimation; EM; High Mobility; NBI; OFDM; high mobility;
Journal_Title :
Wireless Communications Letters, IEEE
DOI :
10.1109/LWC.2015.2424704
