A novel code assignment scheme for W-CDMA systems

The third-generation wideband CDMA (W-CDMA) systems support the relative higher and variable bit rate transmissions for applications with various quality-of-service (QoS) requirements. Code assignment and reassignment schemes in W-CDMA are essential, with the aim of boosting utilization of codes. A dynamic code assignment scheme (DCA) is proposed for traffic with various QoS classes introduced by Universal Mobile Telecommunication System (UMTS). From the simulation results, the proposed DCA can reduce the new call blocking probability and thus improve the system utilization for W-CDMA.

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