A Fast Code Assignment Strategy for W-CDMA Rotated-OVSF Tree with Code-Locality Capability

Abstract

In this paper, a new channelization code scheme, namely ROVSF (Rotated-Orthogonal Variable Spreading Factor), is developed to quickly seeking available codes, compared to using the conventional OVSF (Orthogonal Variable Spreading Factor) in the WCDMA system. When new call enters the system, the OVSF-based scheme always takes lots of time to search for a feasible code. Our ROVSF-based scheme provides a fast code assignment strategy based on new proposed code tree structure. Observe that, our ROVSF scheme offers the same code capability with the OVSF-based schemes, and inherited most of the properties of OVSF code tree. Finally, the simulation result illustrates that the fast-searching achievement of our ROVSF-based scheme.