In this thesis a signal level simulator in uplink is implemented according to the physical layer specification of the IMT-2000 WCDMA system. The analytical WCDMA system through the use of linear algebra techniques is shown. Channel model is built on the classical understanding of fading, Doppler spread, delay spread, and incorporate additional concepts such as direction of arrival and antenna array geometry. PN sequence properties and generation are studied. Spreading and scrambling techniques are present. RAKE receiver and multiuser detection are described, and spatial processing in smart antenna are reviewed. A simulation tool in Matlab is developed in this work.