Provided by:International Journal Of Electronics,Communication And Soft Computing Science &Engineering (IJECSCSE)
In 3G multi-rate wireless communication system such as UMTS, the enhancement of data rate is performed by reducing the spreading factor. This is made by using so called Variable Spreading Factor (VSF) codes. Small spreading factor causes the saturation of Inter-Path Interference (IPI) and near-far problem. This implies that amplitude of transmission signal has to be higher in order than constant energy per bit as required by the system. This amplitude differs due to different data rate.