Abstract
Electromagnetic spectrum is too cluttered to add additional broadband channels of high data rate and bandwidth. Free space optical (FSO) communication is one of the most dominant optical wireless communication systems, which provides huge and licensed free spectrum, non-interfering link, and high data rate. Despite of having above-mentioned advantages, the FSO links are very sensitive to bad weather conditions (i.e., fog, snow, dust, and their combination). Therefore, there is a dire requirement to develop a system that can overcome issues of individual communication system and adjust the current demand of new broadband channels. Adaptive FSO-radio frequency (RF) communication system is proposed to tackle the individual channel issues. A novel throughput maximization algorithm (TMA) is developed for the adaptive hybrid FSO-RF channel. Performance of the proposed algorithm for adaptive hybrid communication system is analyzed considering the regular and right-regular low density parity check (LDPC) code under various weather conditions. Simulation results show that the TMA performs well under all weather conditions and gives a performance gain of up to 2.25 dB considering the right-regular LDPC code. From the presented results, it is also seen that the suggested communication system optimizes mapping schemes, bit proportions for each channel, and puncturing ratios adaptively for different degree variable nodes in worst weather conditions.