Enhancing Security Performance of Optical Wireless Communication with Acoustic Waves in Fog Conditions

Optical wireless communication is an innovative and cost-effective family of communication systems which rely on modulated lights for high-speed and secure networks. However, sub-optimum atmospheric conditions, natural or man-made, can severely affect the performance of the optical link, because suspended small particles with a different refractive index scatter the light and which results in the loss of power and ultimately reduces the link availability. Furthermore, scattered light can allow third parties to intercept the line-of-sight and eavesdrop on the signals. To solve this crucial issue, we propose applying acoustic signals in the desired target area to enhance both the performance and security of the link. Results from the experimental test using a laboratory fog chamber and 1.2 m wireless optical link show using an acoustic wave strategy (AWS), the eavesdropper window can be reduced by up to 40% while simultaneously improving the main links' visibility, and therefore the related performance metrics.