Inter-satellite optical wireless system

Abstract

Nowadays, the usage of Optical fibers and optical devices are evolved. Optical system has been used in many applications including space communication, which is satellite communication system. Laser technology is one of the advance optical technologies on satellite communication that is using optical wireless system. This chapter will discuss about the laser’s application in satellite and how it works. Space-based, free-space optical communications is a concept that has been around for many years. In the last few years, however, there has been impressive activity to bring the concept to fruition in civilian and government non-classified projects. Today's market for space-based optical communications is primarily inter-satellite links (ISLs) which are the main focus of this chapter. There is also a place for high data rate (many Gbps) space-earth links, though propagation effects due to the atmosphere and weather make this a much more difficult link. Laser satellite communication (LSC) which is an optical wireless system, uses free space as a propagation medium for various applications such as inter-satellite communication or satellite network. An LSC system includes a laser transmitter and an optical receiver. Space to space crosslink’s will afford information transfer to even the most remote site on earth without the expense of intermediate ground relay stations. Laser crosslink will enable this transfer of data between satellites at rates compatible with the ground fiber networks. This is an exciting era for space laser communications. The receiver configurations of satellite have improved with advanced technique in the area of silicon avalanche photodiodes (APDs) and fiber preamplifiers [1].