Code assignment and reassignment to reduce new code blocking in WCDMA networks

Orthogonal Variable spreading factor (OVSF) codes supports variable data rates using different physical channels. For better utilization of OVSF codes, code assignment must be done so as to reduce number of reassignments in future and reassignments must be done so as to reduce future code blocking. In this paper, code assignment and reassignment design is proposed which uses call duration of ongoing calls to decide best candidate for new call and reduce future code blocking. The simulation results show that this design can reduce the impact of reassignment process to system efficiently with less call establishment delay due to less number of code searches and maintain low call blocking ratio at the same time.

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