Optics Letters

Asymmetric cryptosystem based on phase-truncated Fourier transforms

Wan Qin, Xiang Peng

Published Jan 9, 2010• 606 citations

Abstract

We propose an asymmetric cryptosystem based on a phase-truncated Fourier transform. With phase truncation in Fourier transform, one is able to produce an asymmetric ciphertext as real-valued and stationary white noise by using two random phase keys as public keys, while a legal user can retrieve the plaintext using another two different private phase keys in the decryption process. Owing to the nonlinear operation of phase truncation, high robustness against existing attacks could be achieved. A set of simulation results shows the validity of proposed asymmetric cryptosystem.

DOI: 10.1364/ol.35.000118

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