Security enhancement of an integrated mode division multiplexed VLC system using two-dimensional WMZCC codes

The incorporation of Visible Light Communication (VLC) in the military services, different organizations, and homes is prominently seen and it becomes an important area to explore. In VLC systems, optical code division multiplexing (OCDMA) is a prominent multiple access method that provides great security while serving several users. Multicode keying, wavelength conversion, quantum key distribution, and optical logic gates are some of the most often utilised security improving techniques, although they are expensive and complicated. This study introduces the two-dimensional (2D) weight managed Zero Cross Correlation (WMZCC), non-adjacent weights (W) and time (t) dimension based optical code with increased security. Comparison of different Hermite Gaussian (HG) and Laguerre-Gaussian (LG) modes has been performed in 5 user x 100 Gbps OCDMA system over 5 m employing mode division multiplexing (MDM) in 2D-WMZCC codes in terms of Q factor and bit error rate. It is observed that HG modes in proposed 2D-WMZCC codes show more resistance to data eavesdropping than LG modes.