A Low Complexity Algorithm for Generating Turbo Code s-Random Interleavers

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 criteria 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.

On the Performance of Interleavers for Quantum Turbo Codes

“…All the QTC schemes in References [ 3 , 4 , 5 , 6 , 7 , 8 , 9 ] are based on random interleavers , that is, the interleaving patterns are selected at random. However, it is known from classical turbo codes that the usage of interleavers with some added structure is beneficial to reduce either the error floors or the memory requirements [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. In order to show that interleaver design is also beneficial when implementing quantum turbo codes, we consider the following three types of classical interleavers.…”

“…The first classical interleavers considered here are the S-random interleavers [ 11 ]. They are randomly generated by imposing the following condition on the interleaving distance or spread ( S ): If the heuristic recommendation is satisfied, where N is the blocklength, S -random interleavers can usually be produced in reasonable time by repeatedly generating random integers until condition ( 4 ) is satisfied [ 11 , 15 ]. However, as indicated in Reference [ 18 ], reasonable values of S are sometimes lower when N is large.…”

“…The QTCs proposed in the literature [ 3 , 4 , 5 , 6 , 7 , 8 , 9 ] use the so-called random interleaver. However, it is known from classical turbo codes that interleaving design plays a central role in optimizing performance, specially when the error floor region is considered [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. Motivated by such studies, in this paper we investigate the application of different types of interleavers in QTCs, aiming at reducing the error floors.…”

A better understanding of the performance of rate-1/2 binary turbo codes that use odd-even interleavers

“…is the permutation function. In order to efficiently simulate the ensembles we took advantage of the algorithm described in [19]. The results are shown in Figs 2a and 2b with S taking the values 20 and 21, respectively.…”

Μελέτη της συμπεριφοράς και αξιολόγησης των συστημάτων Turbo κωδικοποίησης και Turbo Trellis κωδικοποιημένης διαμόρφωσης σε περιβάλλον θορύβου και διαλείψεων

“…30], ε νπνία επηηξέπεη ηε ζρεδίαζε αλαδηαηαθηώλ κε πεξηζζνηέξα θξηηήξηα, θαη ε νπνία δίλεη απνηειέζκαηα ζε εύινγν ρξνληθό δηάζηεκα.ΑΞΝΘΥΓΗΘΝΞΝΗΖΡΖΠΖ Δηθόλα 4 παξνπζηάδεη ην κπινθ δηάγξακκα ηνπ απνθσδηθνπνηεηή πνπ αληηζηνηρεί ζηνλ turbo θώδηθα ξπζκνύ 1/3 πνπ πεξηγξάςακε ζε πξνεγνύκελε παξάγξαθν. Ζ είζνδνο ζηνλ turbo απνθσδηθνπνηεηή είλαη νη παξακνξθσκέλεο BSPK αθνινπζίεο r1k, r2k θαη r3k, νη νπνίεο αληηζηνηρίδνληαη ζηα θσδηθά bits x1, x2 θαη x3.…”