Table of Contents
Advances in Electrical Engineering
Volume 2014 (2014), Article ID 282108, 6 pages
http://dx.doi.org/10.1155/2014/282108
Research Article

Parameter Estimation of Turbo Code Encoder

1Faculty of New Sciences and Technologies, University of Tehran, Tehran 14399, Iran
2Newracom, Irvine, CA 92618, USA

Received 29 May 2014; Revised 15 August 2014; Accepted 27 August 2014; Published 18 September 2014

Academic Editor: Nikos D. Lagaros

Copyright © 2014 Mehdi Teimouri and Ahmadreza Hedayat. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The problem of reconstruction of a channel code consists of finding out its design parameters solely based on its output. This paper investigates the problem of reconstruction of parallel turbo codes. Reconstruction of a turbo code has been addressed in the literature assuming that some of the parameters of the turbo encoder, such as the number of input and output bits of the constituent encoders and puncturing pattern, are known. However in practical noncooperative situations, these parameters are unknown and should be estimated before applying reconstruction process. Considering such practical situations, this paper proposes a novel method to estimate the above-mentioned code parameters. The proposed algorithm increases the efficiency of the reconstruction process significantly by judiciously reducing the size of search space based on an analysis of the observed channel code output. Moreover, simulation results show that the proposed algorithm is highly robust against channel errors when it is fed with noisy observations.