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Chaotic-Sequence-Based Channel Estimation Algorithm for Secure Optical OFDM Systems

In this paper, in order to improve the security of optical OFDM system, we propose a new method to generate the pilot sequence of channel estimation using chaotic sequence. Firstly, we assign initial values to chaotic system, and calculate a chaotic sequence through an iteration method, then converting it into a binary sequence as the pilot of a DFT-based channel estimation algorithm. When the receiving end doesn’t know the chaotic-sequence-based pilot, the system will have very high BER, and can not restore the original data, which indicate that the new method provides a certain degree of security for optical OFDM systems without increasing the system complexity.