The NLM interleaver design for IDMA system

Abstract

International audienceThe choice of a "good" interleaver in IDMA systems must demonstrate that the interleavers do not "collide" and easy to generate. In this paper, we develop a new one-dimensional system, completely based on the logistic map: "New Logistic Map (NLM)". We use the NLM to generate an interleaver matrix for IDMA systems: NLM Interleaver. The simulation results of chaotic dynamical behaviours show that the NLM is a chaotic system and has an ideal distribution. It is also characterized by its wide range of definition, and depends on the number of the desired real values. In addition, the correlation performances of NLM Interleaver are the same as those found in the literature for different interleaver designs

Performance analysis of modified tent map interleaver in IDMA systems

“…which describes a [7,4,3] Hamming code, defines for each codeword c = (c 6 , c 5 , c 4 , c 3 , c 2 , c 1 , c 0 ) following 3 control equations…”

“…This technique overcomes the limitations of CDMA system such as multiple access interference (MAI), and intersymbol interference (ISI) [1][2][3]. Beside user separation, interleavers are also used to randomize the error bursts.…”

“…The research of RLL-ECC can be traced back to the late eighties of the 20-th century [1][2]. In [3] a new modified construction was presented yielding improved RLL properties for DC free error-correcting codes. In [4] trellis RLL-ECCs were constructed.…”

“…The spreader and encoder are combined and belonging to code word c, which is same for all users. Next, chips are interleaved by a specific interleaving pattern (based on modified chaotic Tent map) to produce transmitted chip sequence x n [3]. The receiver for IDMA system of k simultaneously transmitting users are comprised of multiuser detector (MUD) and posterior probability (APP) decoders in connection with user specific interleavers.…”

A Fast Computational Interleaver Design for Iterative IDMA Scheme Based on Tent Map and Chaos

“…So, the use of interleavers enhances the system throughput in multiuser environment and the bursty channel appears like random error channel. The interleaver based multiple access is popularly named as Interleave division multiple access [4][5][6][7].…”