9
Radio Resource Management
9.1 Introduction
Radio Resource Management (RRM) algorithms are responsible for efficient utilization of the air interface resources. RRM is needed to guarantee Quality of Service (QoS), to maintain the planned coverage area, and to offer high capacity. The family of RRM algorithms can be divided into handover control, power control, admission control, load control, and packet scheduling functionalities. Power control is needed to keep the interference levels at minimum in the air interface and to provide the required quality of service. WCDMA power control is described in Section 9.2. Handovers are needed in cellular systems to handle the mobility of the UEs across cell boundaries. Handovers are presented in Section 9.3. In third generation networks other RRM algorithms—such as admission control, load control and packet scheduling—are required to guarantee the quality of service and to maximize the system throughput with a mix of different bit rates, services and quality requirements. Admission control is presented in Section 9.5 and load control in Section 9.6. WCDMA packet scheduling is described in Chapter 10.
The RRM algorithms can be based on the amount of hardware in the network or on the interference levels in the air interface. Hard blocking is defined as the case where the hardware limits the capacity before the air interface gets overloaded. Soft blocking is defined ...
