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Báo cáo hóa học: " Research Article Coexistence Performance of High-Altitude Platform and Terrestrial Systems Using Gigabit Communication Links to Serve Specialist Users"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Coexistence Performance of High-Altitude Platform and Terrestrial Systems Using Gigabit Communication Links to Serve Specialist Users | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2008 Article ID 892512 11 pages doi 10.1155 2008 892512 Research Article Coexistence Performance of High-Altitude Platform and Terrestrial Systems Using Gigabit Communication Links to Serve Specialist Users Z. Peng and D. Grace Communication Research Group Department of Electronics University of York Heslington York YO10 5DD UK Correspondence should be addressed to Z. Peng kenji0233@hotmail.com Received 31 October 2007 Revised 24 March 2008 Accepted 26 June 2008 Recommended by Ryu Miura This paper presents three feasible methods to serve specialist users within a service area of up to 150 km diameter by using spotbeam gigabit wireless communication links from high-altitude platforms HAPs . A single HAP serving multiple spot beams coexists with terrestrial systems all sharing a common frequency band. The schemes provided in the paper are used to adjust the pointing direction of aperture antennas operating in the mm-wave bands such that the peak carrier to interference plus noise ratio CINR is delivered directly toward the location of the specialist users the schemes include the small step size scheme half distance scheme and beam switch scheme. The pointing process is controlled iteratively using the mean distance between the peak CINR locations and user positions. The paper shows that both the small step size and half distance schemes significantly enhance the CINR at the user but performance is further improved if beams with adverse performance below a specific threshold are switched off or are assigned another channel. Copyright 2008 Z. Peng and D. Grace. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION HDTV is now a hot topic in the consumer electronic space and while content can be readily .