Investigation of Handover in Wcdma
نویسنده
چکیده
Third generation wireless system is based on the WCDMA access technique. In this technique, all users share the same bandwidth simultaneously but with different codes. So in Soft Handoff (WCDMA) new user will demand new OVSF codes. This behavior effectively reduces the total number of available OVSF codes in each cell. The effective available OVSF codes in each cell decreases as the percentage of calls in soft handover increases. Due to their blocking property these codes cannot be used efficiently. So this paper presents a new nonorthogonal variable spreading factor (NOVSF) codes to support a quite large number code candidates for more user used in multi-rate next-generation wireless system. Keywords—WCDMA; UMTS; DS-CDMA; Soft Handoff; OVSF Codes; NOVSF Codes; Code Blocking;
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