Abstract
In this paper, we propose a chaotic interleaving scheme for efficient data transmission with continuous-phase modulation orthogonal frequency-division multiplexing (CPM-OFDM) systems over fading channels. The idea of chaotic maps randomization (CMR) is exploited in this scheme. CMR generates permuted sequences from the sequences to be transmitted with lower correlation among their samples, and hence a better symbol error rate (SER) performance can be achieved. The performance of the proposed approach is tested on the conventional Fast fourier transform OFDM (FFT-OFDM), discrete wavelet transform OFDM (DWT-OFDM), and discrete cosine transform OFDM (DCT-OFDM). The proposed (FFT/DCT/DWT)-CPM-OFDM system with interleaving combines the advantages of frequency diversity and power efficiency from CPM-OFDM and performance improvement from chaotic interleaving. The SER performance of the (FFT/DCT/DWT)-CPM-OFDM system with and without chaotic interleaving is evaluated by computer simulations. Also, a comparison between chaotic interleaving and block interleaving is performed. Simulation results show that the chaotic interleaving scheme can greatly improve the performance of (FFT/DCT/DWT)-CPM-OFDM systems. Furthermore, the results show also that, the (FFT/DCT/DWT)-CPM-OFDM system provides a good trade-off between system performance and bandwidth efficiency.