tailieunhanh - Báo cáo hóa học: " Research Article Performance Evaluation of WiMAX Broadband from High Altitude Platform Cellular System and Terrestrial Coexistence Capability"

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 Performance Evaluation of WiMAX Broadband from High Altitude Platform Cellular System and Terrestrial Coexistence Capability | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2008 Article ID 348626 9 pages doi 2008 348626 Research Article Performance Evaluation of WiMAX Broadband from High Altitude Platform Cellular System and Terrestrial Coexistence Capability Z. Yang A. Mohammed and T. Hult School of Engineering Blekinge Institute of Technology 372 25 Ronneby Sweden Correspondence should be addressed to Z. Yang zya@ Received 1 November 2007 Revised 23 April 2008 Accepted 14 August 2008 Recommended by Marina Mondin The performance obtained from providing worldwide interoperability for microwave access WiMAX from high altitude platforms HAPs with multiple antenna payloads is investigated and the coexistence capability with multiple-operator terrestrial WiMAX deployments is examined. A scenario composed of a single HAP and coexisting multiple terrestrial WiMAX base stations deployed inside the HAP coverage area with radius of 30 km to provide services to fixed users with the antenna mounted on the roof with a directive antenna to receive signals from HAPs is proposed. A HAP cellular configuration with different possible reuse patterns is established. The coexistence performance is assessed in terms of HAP downlink and uplink performance interfered by terrestrial WiMAX deployment. Simulation results show that it is effective to deliver WiMAX via HAPs and share the spectrum with terrestrial systems. Copyright 2008 Z. Yang et al. 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 Delivering worldwide interoperability for microwave access WiMAX services in the GHz band from HAPs is an effective way to provide wireless broadband communications. HAPs recently proposed novel aerial platforms operating at an altitude of 17-22 km have been suggested by the .