A Combined Time and Frequency Algorithm for Improved Channel Estimation in TDS-OFDM

Ming Liu (1) , Matthieu Crussière (1) , Jean-François Hélard (2)

1 IETR - Institut d'Electronique et de Télécommunications de Rennes
2 IETR - Institut d'Électronique et des Technologies du numéRique

In contrast to the classical cyclic prefix (CP)-OFDM, the time domain synchronous (TDS)-OFDM employs a known pseudo noise (PN) sequence as guard interval (GI). Conventional channel estimation methods for TDS-OFDM are only based on the PN sequence and consequently suffer from intersymbol interference. This paper proposes a novel two-stage channel estimation method which combines the estimation results from the PN sequence and, most importantly, the estimation results obtained from the OFDM data symbols. A simple feedback loop that excludes the channel decoder is employed for the OFDM data based estimation. The MMSE criteria is used to obtain the best combination results and an iterative process is proposed to progressively refine the estimation. Both MSE and BER simulations are carried out to prove the effectiveness of the proposed algorithm in the DTMB system which is based on TDS-OFDM signalling.

Mots clés: channel estimation; data-aided; TDS-OFDM

Domaines: Réseaux et télécommunications [cs.NI]; Traitement du signal et de l'image [eess.SP]; Traitement du signal et de l'image [eess.SP]

Ming Liu, Matthieu Crussière, Jean-François Hélard. A Combined Time and Frequency Algorithm for Improved Channel Estimation in TDS-OFDM. IEEE International Conference on Communications (ICC 2010), May 2010, Cape Town, South Africa. pp.1-6, ⟨10.1109/ICC.2010.5501781⟩. ⟨hal-00491817⟩