Multicarrier chaotic communications in multipath fading channels without channel estimation

• Published in: AIP advances Vol. 5; no. 1; pp. 017139 - 017139-8
• Main Authors: Wang, Shilian, Zhang, Zhili
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 01.01.2015; AIP Publishing LLC
• Subjects: Bandwidths; Channels; Computer simulation; COMPUTERIZED SIMULATION; EFFICIENCY; Interception; Keying; MATERIALS SCIENCE; Orthogonal Frequency Division Multiplexing; SIGNALS; Subcarriers; Symbols
• ISSN: 2158-3226; 2158-3226
• DOI: 10.1063/1.4906984

A multi-carrier chaotic shift keying(MC-CSK) communication scheme with low probability of interception(LPI) is proposed in this article. We apply chaotic spreading sequences in the frequency domain, mapping a different chip of a chaotic sequence to an individual orthogonal frequency division multiplexing(OFDM) subcarrier. In each block size of $M$ OFDM symbols, we use one pilot OFDM symbol inserted time-spaced in all-frequency to transmit the reference chaotic signal and use the other M-1 OFDM symbols to transmit the information-bearing signals each spreaded by the reference chaotic signal. At the receiver, we construct a differential detector after DFT and recover the information bits from the correlations between the pilot OFDM symbol and the other M-1 OFDM symbols in each block size of M. Performance analysis and computer simulations show that the MC-CSK outperforms differential chaos shift keying(DCSK) in AWGN channels with high bandwidth efficiency for the block size of M=2 and that the MC-CSK exploits effectively the frequent diversity of the multipath channel.