Fair single code and multi code assignment schemes for OVSF based networks

OVSF codes in the WCDMA system provide facility for variable data rate support. The applications with different rates must be served in fair manner. The paper propose a fair single code and multi code design so that the OVSF code tree is not over-served for single type of application. The single code design considers tree partitioning adaptive to the different user rates. The multi code design is based upon the selection of multi code out of number of available options such that the code usage leads to most fair assignment. The average code blocking may not be significantly reduced, but for individual rates the code blocking is not significantly high for one or more schemes. Simulation results are presented to show the superiority of the proposed designs.