An Optical Payload for Cubesats

Optical wireless communications provide a promising, high bandwidth alternative to radio communications, where high performance links are desired. For large satellites (say, wet mass\u3e1000kg), laser cross links have been successfully established since 2001 by various space agencies in Europe and Japan. Thus far, the cross-links have been able to achiever data rates in Gbps range for distances greater than 10,000km. Such gains would be monumental improvement for communications in small satellite domain (say, wet mass for Cubesats \u3e10kg), where the typical communications payload users radio antenna that achieve an average data rate of 10kpbps.This paper proposes a promising laser communication system for CubeSat. First, a study of the laser crosslink system of large satellites is provided. Then, the subsystems of the larger satellite laser communications are analyzed for suitability in the CubesSat frame. Each subsystem is further analyzed in terms of functionality, contribution to the weight of the optical payload and power requirements. The parameters of the larger system are then redesigned to meet the size, weight and power constraints of the CubeSat. The new system is simulated for performance and various candidate scenarios are discussed