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We propose an analysis of reverse link CDMA multispot beam stratospheric platforms (SPF) in this paper. The SPF iscurrently proposed as a novel wireless technology for the development of the next generation fixed and mobilecommunications. The geometry of this technology is different from that of the terrestrial but rather similar to thesatellite based cellular system. However, evaluation on the CDMA system capacity of this technology has not beenmuch reported. This paper addresses all possible multiple access interference analyses including the effects of channelfading and shadowing in order to evaluate the system capacity. Single SPF and multiple SPF model are evaluated underperfect power control and imperfect power control. The results indicate that in SPF systems the reverse link CDMAcapacity is significantly reduced because of the power control imperfections. Moreover, in multiple SPF model theinterference caused by the users in overlapped region is not trivial. We found that because of this problem the capacityis reduced for both speech and real-time data applications compared with the single SPF model even though theassumption of perfect power control can be made. In order to improve the system capacity we proposed two methods,first is to increase the minimum elevation angle definition for each platform and the second is to employ an adaptiveantenna. |
