International Journal Of Engineering And Computer Science
Orthogonal Variable Spreading Factor (OVSF) codes have been proposed for the data channelization in W-CDMA access technology of IMT-2000. OVSF codes have the advantage of supporting variable bit rate services which is important for emerging multimedia with different bandwidth requirements. OVSF codes are employed as channelization codes in W-CDMA. Any two OVSF codes are orthogonal if and only if one of them is not a parent code of the other. Therefore, when an OVSF code is assigned, it blocks entire ancestor and descendant codes from assignment because they are not orthogonal to each other.