Coexistence performance of high altitude platform and terrestrial systems sharing a common downlink WiMAX frequency band

The coexistence performance when high altitude platform (HAP) and terrestrial WiMAX systems coexist within the same coverage area sharing a common 5.75 GHz frequency band is investigated. Using percentage coverage area served and percentage coverage area not served defined by set theory, it is shown how HAP and terrestrial systems can coexist within the same coverage area provided a low rate modulation scheme is used, and users have a relative narrow antenna beamwidth in the order of less than 30/spl deg/.