HAP-GEO optical links: Performance analysis under weak turbulence conditions

High altitude Platforms represent a very attractive solution to enhance space communications in terms of available capacity and system topology. They can be geared with multi-functional payload, both for communications and Earth Observation missions. Thanks to their opportune position, they are the key for optics and RF technology integration in space communications. In this paper we evaluate the feasibility of an optical HAP-GEO-HAP link over more than 80,000 km above the stratosphere. In particular, we consider a system based on 1550 nm technology, that exploits the potentialities of DPSK modulation format with Direct-Detection balanced interferometer receiver, and optical amplifier.