Theoretical study on the effectiveness of optical filters to suppress orientation-based solar light noise.

Abstract

It is well established in the literature that the performance of an underwater optical wireless communication (UOWC) system degrades due to various channel-based and environmental attributes. So far, consistent performance by a UOWC system has not been discussed when the system receiver (Rx) is positioned at a certain depth and takes on different orientations, i.e., vertically upward or downward, and horizontally left or right. This paper discusses the UOWC system performance when the Rx points in three different orientations and captures the modulated light signal and different intensities of solar light. We carry out a detailed comparative performance analysis of the UOWC Rx system considering various optical components, such as a colored glass optical bandpass filter, optical thin-film interference filter, and optical wide-field birefringent filter (OWFBF), which are mounted in front of the UOWC Rx to suppress solar light noise interference for different orientations. We observe that the same UOWC Rx behaves differently in all three orientations and the OWFBF outperforms.