Link performance improvement via design variables optimization in LED-based VLC system for inter-satellite communication

Abstract

In our previous paper, we examined the utility of LEDs for inter-satellite communication (ISC) in multiple small satellite networks and proposed an approach of the physical layer design that meets the requirements of the platform in terms of the critical physical layer design variables. These variables (or parameters) include the LED transmit power, photodetector active area, receiver bandwidth and link distance. One of the most important tasks for the visible light communication (VLC) system designer is how to ensure the required balance or trade-off among these variables in order to achieve the desired performance. In this work, we employed multi-objective optimization to determine physical layer design variables at which the signal-to-noise ratio (SNR) at the VLC receiver is maximized. We used the Non-dominated Sorting Genetic Algorithm II (NSGA-II) in MATLAB to determine the Pareto front of two conflicting objective functions, and then extracted the optimal solution using the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). Analysis of the optimal solution showed that it yielded the maximum SNR within the set of non-dominated solutions at the Pareto front. We showed that using multi-objective optimization techniques for assignment of parameter values can yield more than 3 dB improvement in the SNR.