A Low Complexity Algorithm for Generating Turbo.pdf
4星 · 超过85%的资源 需积分: 22 56 浏览量
2013-04-12
23:50:37
上传
评论
收藏 229KB PDF 举报 
Wireless Pers Commun (2008) 46:365–370
DOI 10.1007/s11277-007-9439-0
A Low Complexity Algorithm for Generating Turbo
Code s-Random Interleavers
Kostas V. Koutsouvelis · Christos E. Dimakis
Published online: 20 December 2007
© Springer Science+Business Media, LLC. 2007
Abstract In this paper we present a low complexity algorithm based on the bubble search
sorting method that can be used to generate Turbo code interleavers that fulfill several crite-
ria like spreading (s-randomness), code matched criteria and even the odd–even property for
Turbo Trellis Coded Modulation. Simulation results show that for s <
√
N/2 the algorithm
is extremely efficient for short to medium interleaver lengths.
Keywords Turbo codes · Turbo Trellis Coded Modulation (TTCM) · s-Random ·
Code-matched interleaver (CMI)
1 Introduction
The initial discovery of Turbo codes by Berrou et al. [1] in 1993 opened an enormous new
field for research in communication theory. Since then, researchers worldwide have done
major efforts in order to reveal the secrets of the excellent performance of the new turbo
codecs and even to improve them. Very soon [2,3], the interleaver was identified to play a
central role on the performance of the overall turbo coding scheme, since it affects the dis-
tance spectrum of the code. Furthermore, for high SNR, it determines the error floor region
where the BER curve does not decrease as quickly as in the waterfall region. Several types of
interleavers have been constructed in order to improve the performance of the turbo coding
system. In the following we will give a brief overview of the most popular interleavers:
S. Dolinar et al. [2] verified that the performance of a turbo coding scheme could be
improved if the interleaver has the capability to eliminate input sequences that produce code-
words of low Hamming weight. They proposed a pseudorandom permutation, the s-random
interleaver (s denotes the spread factor) with the following property: if π is the interleaving
law the new selected position π(i) is accepted only if its absolute difference from the previous
s selected numbers π(j) is greater than s. This property is expressed mathematically as:
K. V. Koutsouvelis (
B
) · C. E. Dimakis
Aristotle University of Thessaloniki, Thessaloniki, Greece
e-mail: koutote@yahoo.gr
123
资源评论
Supsen2013-08-11A Low Complexity Algorithm for Generating Turbo Code s-Random Interleavers_Springer_2008 方法比较传统
hellocate2015-05-09算法比较一般，有个程序是按这个编的，不得不看。
