'VSB Technical University of Ostrava, Faculty of Electrical Engineering and Computer Sciences'
Doi
Abstract
This paper proposes a novel linear precoding
method for Orthogonal Frequency Division Multiplex-
ing (OFDM) based on the employment of the chaotic
waveforms generated by the fourth-order chaotic os-
cillator and orthonormalized by the Gram-Schmidt
process. The proposed linear precoding method
is aimed to increase resilience to the multipath
propagation issues and reduce the Peak-to-Average
Power Ratio (PAPR) of the transmitted signal.
Moreover, the chaotic waveform enables novel timing
synchronization methods to be implemented in the re-
ceiver. The modeling of baseband Linear Precoded
OFDM (LP-OFDM) data transmission system with
Rayleigh channel has been performed in Simulink en-
vironment to validate the proposed method and to com-
pare the performance to the classic precoding meth-
ods, such as Walsh-Hadamard Transform (WHT).
Experiments have shown that in a high Signal-to-Noise
Ratio (SNR) scenario, the employment of the novel
precoding scheme allows reducing Bit Error Ratio
(BER) by several dB compared to non-precoded OFDM.
The proposed precoding method leads to the reduction
of PAPR; however, it is not as efficient as classi-
cal precoding schemes, such as WHT. Experimental
evidence of synchronization of the chaotic oscillators
within 50 samples long time interval is presented