 the AMR codec with CS 12.2 kbps. A higher RAB rate is suitable for the UEs which are near the mobile station in low loaded radio cells and lower RAB rates are assigned for far-off UEs in high loaded cells. 3.3.4.2 Radio Resource Management (RRM) The Radio Resource Management (RRM) is responsible for an efficient utilization of the air interface resources and for provisioning and guaranteeing QoS [Tür07]. The UMTS RRM 3.3 UMTS Release 99 algorithms are separated into two categories: the network based functions and the connection based functions. Network based functions are Admission Control, Load Control and Packet Scheduling, while connection based functions are Handover and Power Control The following briefly describes the role of each function: Admission Control decides whether a new call can be admitted and/or a current call can be modified, according to the available capacity of WCDMA network in terms of power and allowed interference. The admission control functionality is used to avoid system overload and to provide the planned coverage. Load Control resolves and prevents overload or congestion situations in the network, which may occur due to traffic fluctuations, user mobility or channel variations. Power Control manages the transmit power of the UE and base station, which results in less interference and allows more users on the same carrier. Handover is required in cellular networks to support the user mobility. There are in principle three types of handovers in UMTS networks. 1. Hard handover also exists in GSM networks, that is, at any time only one physical connection is maintained. The handover takes place when the mobile user moves between a WCDMA network and a network of different radio technology (e.g. between UTRAN and GSM), or when the mobile user changes between different carriers of the same WCDMA network. 2. Soft handover is when a mobile station communicates simultaneously with up to three cells from different Node Bs. On the downlink, the data is broadcast over the Node Bs and combined ag