The book introduces an overview about one of the third generation (3G) mobile networks, known as Universal Mobile Telecommunications System (UMTS) networks, which consists of Universal Terrestrial Radio Access Network (UTRAN) and the Core Network (CN). The UTRAN has many interfaces, but the book focuses on the Uu interface which is between the User Equipment (UE) and the UTRAN. That interface is based on Wideband Code Division Multiple Accessing (WCDMA) system. The protocol architecture of UMTS is composed of two planes; the control plane and the user plane. The book is concerned on the control plane which has the Radio Resources Control (RRC) protocol to manage the control signal at the Uu interface between the UE and the Radio Network Controller. The main goal of the book is to design, implement and test the building blocks of Radio Resources Controller of the WCDMA system. Also, the book presents one of nuclear applications that is based on WCDMA. This application includes design, implementation and simulation of Radiation Monitoring network as a pilot prototype model.