Information Theoretic Analysis and Performance Gains of 3-Color Shift Keying

Abstract

In this letter, we investigate the information theoretic performance of 3-Color Shift Keying (3-CSK), a promising modulation scheme for visible light communications that is based on the use of sequences of symbols. More specifically, considering its advantages, which include improved error performance and lower power consumption compared to 4-CSK and On-Off Keying, we evaluate its performance in terms of the maximum achievable rate, which is expressed as a function of the number of symbols per sequence, while a closed-form lower-bound and a tractable approximation are also obtained. Monte-Carlo simulations of the maximum achievable rate verify the analysis and illustrate that 3-CSK outperforms 4-CSK, when channel state information is not available at the receiver, with 3-CSK -in contrast to 4-CSK- reaching its maximum capacity in this scenario. Finally, to get further insights on the inferred 3-CSK gains, the bit-error-rate is also analyzed under different channel realizations, assuming no channel state information is available.