Optical Design of Multi–channel Free Space Optical Communication for Inter–satellite Links

In the upcoming low Earth orbit (LEO) satellite constellations, free space optics (FSO) inter-satellite links between two nodes will be incorporated, presenting multiple advantages. These advantages include the use of smaller antenna sizes that reduce the weight and volume of the smaller form factor, saving satellite launching and deployment resources, lowering power consumption, and facilitating higher data rates. Additionally, FSO links offer intrinsic security due to their high directivity and narrow beam width, resulting in no interference. Although FSO provides benefits, its channel capacity requires improvement in comparison to radio-frequency link (RF-Link). The focus of this paper is on presenting an optical design for multi-channel free space optical communication employed in inter-satellite links.