An OFDM-Based Pre-Coded Chaos Shift Keying Transceiver for reliable V2V Transmission

In this correspondence, we propose a novel orthogonal frequency division multiplexing based pre-coded chaos shift keying (OFDM-PC-CSK) transceiver for reliable vehicle-to-vehicle (V2V) communications. In this design, different from traditional OFDM-aided differential chaos shift keying (OFDM-DCSK) systems, we remove the delivery of reference chaotic signals and utilize the diagonalization principle for information transmissions to achieve better reliability than the differential demodulation in OFDM-DCSK. At the transmitter, we construct the chaotic phase vector with chaotic sequences having different initial values, which are then combined with the discrete Fourier transform (DFT) matrix and a conjugate phase matrix of an eigenvalue matrix to compose a precoder. After precoding, the user data are modulated by the chaotic circulant matrix and transmitted over multiple subcarriers. At the receiver, reverse operations are conducted. Subsequently, we derive the theoretical bit error rate (BER) over V2V channels, the spectrum efficiency and the computational complexity. Simulation results validate the theoretical analysis, and demonstrate that the OFDM-PC-CSK system outperforms the counterpart schemes with better reliability and security performances over V2V channels.