A special attack on the asymmetric cryptosystem based on phase-truncated Fourier transforms

We analyze the security of a recently proposed asymmetric cryptosystem that based on the phase-truncated Fourier transforms (PTFTs), and describe a specific attack method to break the cryptosystem. This specific attack, which is based on a two-step iterative amplitude retrieval approach and works by using the public keys and ciphertexts, would allow an attacker to reveal the encrypted information and the decryption keys that generated in the encryption procedure. The numerical simulation results, which are given to show the effectiveness of the proposed specific attack, imply that some appropriate measurements should be made to enhance the resistance of the PTFT-based cryptosystem against the specific attack when it is used as a public-key cryptosystem.