A VOHE System for Underwater Communications

Abstract

This paper presents a new method for encrypting holographic information based on optical and acoustic signals called a Virtual Optical Holographic Encryption (VOHE) system for underwater communications that can be applicable for communications between deep submergence research vehicles. The transmission medium is composed of a combination of optical signals and acoustic signals together to form the VOHE system for transmitting system information. The optical encryption system provides essential parameters for constructing secure communications such as the propagation wavelength (λ) and focal length (f) of the Fourier lens, which are considered as keys for implementing encryption and decryption processes. An expanded RSA (ERSA) algorithm using a complex function sends system information (λ, f) as a message to a receiver. To determine accuracy of the information retrieved by the proposed technique, the minimum mean square error (MSE) was conducted to evaluate the accuracy of the received signal. The VOHE system employs virtual optical encryption system was simulated based on COMSOL Multiphysics simulation software. Finally, the National Institute of Standards and Technology (NIST) method and Pollard’s rho method were separately applied to evaluate the proposed ERSA algorithm. Obtained results showed that ERSA is able to achieve a more significant security level than RSA.