Improve the Performance of Transferring WiMAX OFDM Signals Over Laser Communication Links Based on Optimum Gain of Laser Transmitter

Abstract

A high-altitude platform (HAPs) that can provide high data-rate wireless services is one of the most modern technologies where a WiMAX (IEEE 802.16) base station carried and implemented over its board. HAPs can be considered as a supporting network that wireless broadband services across far distances on the Earth are transferred. The network providing a WiMAX coverage on grounding subscribers includes users on the ground, several HAPs and a satellite. An analog radio frequency (RF) over laser communication (LC) is an optical link, and it is considered as a transmitter link between the HAPs and the satellite in which the WiMAX base station is located. A laser transmitter and an optical receiver are needed to comprise a LC system. Both of them must be strictly aligned to achieve a line of sight link. On the other hand, the transmitter-receiver alignment is probably being defied due to electronic noise and mechanical vibration in the control system causing laser path loss and pointing errors. In other words, the received signal is fading due to the outcome of pointing errors, thus, link performance defects. The goal of this paper is to improve the performance of wireless mobile communication network through minimizing the outage probability of the WiMAX link. This can be done by finding the optimum value of laser transmitter gain, which is finally derived in this paper as a function of , the radial pointing error angle. Lastly, results and performance of outage probability are evaluated by using computer simulation in MATLAB 11.