Improvement of Quantum Steganography Protocol Based on the Tensor Product of Bell States

Abstract

Quantum steganography is the art of hiding secret information in an insecure quantum channel. Recently, it is proposed a quantum steganography protocol based on the tensor product of Bell states to transmit classical 4-bit secret message per round. However, it has permits a small hidden capacity. In this work, an improvement of that quantum steganography protocol to transmit 8-bit secret message per round is proposed. The improved protocol uses tensor product of Bell states and unitary transformations with two groups of sixteen tensor products of two Bell states rather than 256 elements of tensor product of four Bell states. Simulations conducted shows that the improved protocol has superior performance in terms of imperceptibility as well as high security compared with the competitive protocol.