Chaotic Constellation Mapping for Physical-Layer Data Encryption in OFDM-PON

Abstract

A physical-layer encryption scheme is proposed and experimentally demonstrated in orthogonal frequency division multiplexing passive optical network (OFDM-PON). In the proposed multifold encryption scheme, quadratic-amplitude modulation (QAM) symbols are scrambled and distributed onto the complex plane independently. The dynamic parameters of constellation shifting are generated by a 3-D hyper digital chaos, in which a key space of ~10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">162</sup> is created to enhance the security level of OFDM data encryption during transmission. An encrypted data transmission of 9.4-Gb/s, 16-QAM optical OFDM signals is successfully demonstrated over 20-km standard single-mode fiber.