A suboptimal Iterative Method for Maximum-Likelihood Sequence Estimation in a Multipath Context

We present an iterative semiblind suboptimal maximum-likelihood sequence estimation (MLSE) method for single-carrier block transmission over stationary multipath channels. This suboptimal ML detector is based on an iterative least squares with projection (ILSP) algorithm exploiting both the finite alphabet properties of the transmitted signal and its cyclic prefixed structure in order to approach ML detection in a cheap way. Since the initial channel estimate is crucial for the convergence speed of the ILSP algorithm, we propose a new low-complexity stochastic method for providing an initial channel estimate. We therefore rely on some known symbols that are provided by a variant of cyclic prefix only (CP-Only) transmission, known as the known symbol padding only (KSP-Only) technique. The resulting channel model is sufficiently accurate to be used as a starting point for the iterations. The final result is a direct symbol estimation method that is characterised by its low computational complexity and its promising results in terms of bit error rate (BER).

[1]  Robert F. H. Fischer,et al.  A new loading algorithm for discrete multitone transmission , 1996, Proceedings of GLOBECOM'96. 1996 IEEE Global Telecommunications Conference.

[2]  Hamid Jafarkhani,et al.  On the computation and reduction of the peak-to-average power ratio in multicarrier communications , 2000, IEEE Trans. Commun..

[3]  Hikmet Sari,et al.  Transmission techniques for digital terrestrial TV broadcasting , 1995, IEEE Commun. Mag..

[4]  M. Moonen,et al.  Semi-blind channel estimation for block transmissions with non-zero padding , 2001, Conference Record of Thirty-Fifth Asilomar Conference on Signals, Systems and Computers (Cat.No.01CH37256).

[5]  G. Giannakis,et al.  Wireless Multicarrier Communications where Fourier Meets , 2022 .

[6]  Subhasish Subhasish,et al.  Joint blind estimation of channel and data symbols in OFDM , 2000, VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026).

[7]  Biing-Hwang Juang,et al.  The segmental K-means algorithm for estimating parameters of hidden Markov models , 1990, IEEE Trans. Acoust. Speech Signal Process..

[8]  J.A.C. Bingham,et al.  Multicarrier modulation for data transmission: an idea whose time has come , 1990, IEEE Communications Magazine.

[9]  Georgios B. Giannakis,et al.  Wireless multicarrier communications , 2000, IEEE Signal Process. Mag..

[10]  Arogyaswami Paulraj,et al.  Blind separation of synchronous co-channel digital signals using an antenna array. I. Algorithms , 1996, IEEE Trans. Signal Process..

[11]  Nambi Seshadri,et al.  Joint data and channel estimation using blind trellis search techniques , 1994, IEEE Trans. Commun..

[12]  Marc Moonen,et al.  Efficient equalizers for single and multi-carrier environments with known symbol padding , 2001, Proceedings of the Sixth International Symposium on Signal Processing and its Applications (Cat.No.01EX467).

[13]  Luc Deneire,et al.  Training sequence vs. cyclic prefix a new look on single carrier communication , 2000, Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137).

[14]  J.E. Mazo,et al.  Digital communications , 1985, Proceedings of the IEEE.