Background:
In this paper, a chaotic interleaving scheme is proposed for further performance
improvement of Interleave Division Multiple Access (IDMA). Interleavers are used to generate
permuted sequence of signals to be transmitted with optimum correlation.
Methods:
Random interleaving (RI) was the fundamental taxonomy and used to distinguish the different
users in IDMA scheme. The logistic map based chaotic interleaving scheme is suggested for
IDMA. The system is also combined with Minimum Mean Square Error (MMSE) equalizer to combat
the effect of Inter Symbol Interference (ISI).
Results:
For the sake of simplicity, no pulse shaping is assumed at the transmitter and ISI channel is
considered to be a fixed 3 tap channel. Simulations are performed in MATLAB. BPSK modulation is
used. Furthermore, the results show that the IDMA with proposed logistic map based chaotic
interleaver outperforms the traditional random interleaving scheme in terms of BER without the need
of extra memory and computational complexity.
Conclusion:
The obtained results show the noticeable performance improvement of CI-IDMA with
MMSE equalization in deep fading situations. Chaos based interleaver also offers other advantages
such as less requirement of memory and small implementation complexity.