An LMI-based discrete time nonlinear observer for Light-Emitting Diode optical communication

Light-Emitting Diode (LED) optical wireless communication is a potentially low-cost, sustainable approach for enabling high-speed free-space and underwater transmissions within limited range. Establishing tightly controlled line of sight (LOS) between transmitter receiver significant challenge because the angle alignment not directly measured has to be estimated. To address this problem, we propose novel switched-gain discrete-time nonlinear observer an LED-based model in which output functions are composed vector multi-scalar combinations states. Lyapunov function-based analysis that ensures global stability used design proposed each piecewise monotonic region LED functions. Furthermore, prove via quadratic Lyapunov-based constant stabilizing gain no feasible solution when entire range considered. Therefore, suitable derived non-monotonic measurement equations. Simulation results shown together with extensive comparisons Extended Kalman Filter (EKF) illustrate performance design.