RADIO CAPACITY OF DIRECT-SEQUENCE CODE-DIVISION MULTIPLE-ACCESS MOBILE RADIO SYSTEMS

The author evaluates the teletraffic performance of a direct sequence code division multiple access (DS/CDMA) mobile radio system configured with single and multiple cell architectures. The performance investig ation is based on the high-level details of system operation such as c ell layout across the service area; positioning of base stations, dist ribution for the positions of mobile units in a cell, radio channel pr opagation characteristics, transmit power level, power control algorit hm, interference and traffic characteristics. Outage probability is us ed as the main criterion for evaluating the traffic capacity. Using th e parameters of a proposed practical DS/CDMA system, it is found that by adopting a continuous power control scheme, the outage probability is reduced by up to 60% of its value when there is no power control. F urthermore, at a given outage probability, the number of users that ca n be supported by a multicell CDMA system is less (by up to 50%) than the corresponding capacity of a single-cell system.