Semi-Blind Reception Using Joint Channel Estimation in IDMA Systems

Abdelkrim Hamza, Ali Kazem, Gérard Salut

CNRS, LAAS, 7 Avenue du Colonel Roche, Toulouse, France; Univ. de Toulouse, LAAS, Toulouse, France.
LCPTS Laboratoire de Communication et du Traitement du Signal, FEI-USTHB, Alger, Algérie.

DOI: 10.4236/ijcns.2012.57053                

Abstract

In this paper a bi-directional system based on linear channel estimation and data detection using turbo detection algorithm is proposed. By combining channel estimation with an iterative chip-by-chip detection process (inner loop) in an iterative way (outer loop), communications performance can be further increased. We present results on blind reception in case of Interleave Division Multiple Access (IDMA) system when the channel coefficients are unknown. We develop a low-complexity iterative joint channel/code estimation method. The philosophy of the turbo processing is the iterative exchange of related information which yields a substantial improvement of the overall system performance. We analyze the achievable performance of the iterative system proposed. Simulation results demonstrate the efficiency of the proposed algorithms.

Keywords

Channel Estimation; IDMA; Multiuser Detection

Conflicts of Interest

The authors declare no conflicts of interest.

References

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