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

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Abstract. In orthogonal frequency division multiplexing-based interleave division multiple access (OFDM-IDMA) system,all users can transmit their information in the same time and frequency band. In this case the orthogonality between the users is obtained using an interleaving technique. The choice of a "good" interleaver must demonstrate that the interleavers are weakly correlated, do not require either large memory to store it or a large bandwidth to communicate it between the transmitter and the receiver, and must be easy to generate. In this paper, we develop a new one-dimensional chaotic map, completely based on the logistic map: the "New Logistic Map (NLM)". The simulation results of chaotic dynamical behaviours show that the NLM is a chaotic system and has an ideal distribution. We propose also a new design method to construct the interleaver sets by NLM: NLM Interleaver (NLMI). Our design can be used to reduce the computational complexity and memory requirement, and achieve the same correlation performances compared to other designs.

Due to its good performance and low complexity, IDMA is believed to be an important technique for future radio access (FRA). However, its performances are highly affected by the interleaver design. In this paper we propose two contributions to improve the performance of the IDMA. First, we propose a new interleaver design, called "NLM interleaver", which improves the computational complexity, reduces the bandwidth consumption and the memory requirements of the system, provides the quasi-orthogonal spreading codes and interleavers with a high security and offers infinite sets of codes and interleavers based on only one parameter. Second, we propose a new user grouping algorithm based on the correlation function to improve the resources (Codes, Interleavers). All users are divided into several equal-size groups where each group's data transmitted at the same time, over the same frequencies and the same interleaver. The simulation results indicate that the proposed scheme can achieve better performances compared to the existing algorithms.