Color-Shift Keying Code Design in Visible Light Communications Using Finite-State Machines

In this letter, we propose a class of color-shift keying (CSK) codes using finite-state machines for visible light communication (VLC) to achieve higher transmission reliability than their counterparts under the constraint of color perception. The proposed CSK coding scheme was developed to achieve high coding gain by designing a finite-state machine. In our CSK code design, we first established a code design objective function to improve the minimum Euclidean distance, which is based on conceiving a finite-state machine under the target color constraint. Thereafter, we designed the CSK coding scheme, which primarily considers the set-partitioning criterion of the CSK symbol set and the construction of the finite-state machine. Subsequently, we investigated the error performance of the proposed CSK codes in VLC systems. The simulation results confirm that the proposed CSK codes deliver significantly better performance than their counterparts.