Multiple OVSF codes Assignment with Crowded Branch First Strategy in WCDMA Systems

-In this paper, we consider the environment of using multiple OVSF codes to support a request with any data rate. This paper presents the Crowded Branch First strategy for multiple OVSF codes assignment system. Based on the new strategy and the code word generation method, the system can allocate the appropriated codes to each request under the constraint of assigned code amount, and under the constraint of the maximal resource waste ratio. The results show that using two or three codes is sufficient to achieve high performance. Key-Words: Code assignment, OVSF code, Wideband CDMA, Resource management. 1 The work of M-X. Chen was supported by by the National Science Council of Taiwan, R.O.C. under Grant NSC 95-2221-E-216-039