TOTAL CAPACITY IN A SHARED CDMA LEOS ENVIRONMENT

We are interested in determining the feasibility of having multiple se rvice providers share the same spectrum in transponder-type, satellite -based, code-division multiple access mobile communications. To accomp lish this, we compare the total capacity when n systems are operationa l to that when only a single system uses the frequency band. This comp arison is made for both the uplink and the downlink under one of two p ossible constraints, either a maximum power flux density (PFD) limit p er system, or an aggregate PFD limitation. While there are circumstanc es when the total capacity of multiple systems can achieve a greater v alue than that of a single service provider, conditions depend on the degree of shadowing, and whether or not the PFD limit is on a per syst em basis or on an aggregate basis from all systems.,