In this paper, we propose the long range cooperative communication via high altitude platforms (HAPs). The HAPs are temporary platforms placed in the stratosphere, at the typical heights of 17-25 km above the earth surface, which is considered to be a low air density region.
The error performance is analyzed for the proposed source-HAPs-destination cooperative system, where the source and the destination are separated by a very long distance on earth surface. Considering the decode and forward (DF) strategy at the HAPs, we find an accurate closed form expression of average BER for binary phase shift keying (BPSK) constellation.