Location-dependent downlink capacity loss due to introducing a high data-rate user in CDMA cellular systems with multiple low data-rate users

Abstract

Existing code division multiple access (CDMA) cellular systems achieve capacity gains over conventional time division multiple access (TDMA) or frequency division multiple access (FDMA) systems. by assuming a large number of low data-rate and hence low power users uniformly distributed over a cell. In current CDMA proposals for providing higher data-rate packet services, however, burst high data-rate users do not satisfy this assumption and thus the capacity advantage is lost. In this letter, we quantify the capacity loss with focusing on location-dependent aspects of the degradation. This work contributes to a better understanding of the capacity problem encountered when introducing high data-rate packet services with the cellular band where existing low data-rate CDMA systems operate.