Abstract
Orthogonal variable spreading factor channelization codes are widely used to provide variable data rates for supporting different bandwidth requirements in wideband code division multiple access (WCDMA) systems. A new code match scheme for WCDMA code tree management was proposed. The code match scheme is similar to the existing crowed-first scheme. When choosing a code for a user, the code match scheme only compares the one up layer of the allocated codes, unlike the crowed-first scheme which perhaps compares all up layers. So the operation of code match scheme is simple, and the average time delay is decreased by 5.1%. The simulation results also show that the code match strategy can decrease the average code blocking probability by 8.4%.
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Foundation item: Project(60202005) supported by the National Natural Science Foundation of China
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Yang, Zk., Liu, Gr. & He, Jh. New code match strategy for wideband code division multiple access code tree management. J Cent. South Univ. Technol. 13, 265–269 (2006). https://doi.org/10.1007/s11771-006-0121-6
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DOI: https://doi.org/10.1007/s11771-006-0121-6
Key words
- orthogonal variable spreading factor
- code placement strategy
- code match strategy
- code blocking probability