Integrated services from high-altitude platforms: a flexible communication system

In this article the provision of integrated services from high-altitude platforms (HAPs) is discussed, and a flexible communication system for HAP-based communications is identified and analyzed, with particular attention to the delivery of broadband services from HAPs to highspeed trains. The high coding gain required by the proposed scenario is achieved through adaptive concatenated coding schemes, while smart antennas operating with adaptive beamforming algorithms are employed at the ground stations. The simulated system performance based on a multi-antenna model of the stratospheric channel is reported, and the use of HAPs in synergy with terrestrial and satellite systems is discussed.