Enabling multimode wireless access networks using remote radio heads

The deployment of 4G networks is spreading rapidly providing mobile broadband services to the public. 4G technologies are designed to overlay existing 3G networks enabling reusability of several network components. In this way, the coexistence of 3G/4G standards is facilitated. This paper describes the advantages of using distributed base station architectures to provide multimode capabilities. In particular, it focuses on the radio unit, commonly known in industry as remote radio head. Multimode radio units capable of operating according to different wireless standards (WCDMA, LTE and WiMAX) can be proven extremely beneficial for operators especially in terms of operational and maintenance cost. Moreover, remote radio heads can enable effective spectrum management and allocation of radio resources. This is achieved through the advanced software configurability they provide and a flexible control and management plane. Switching between wireless standards becomes easily feasible through firmware upgrading. Finally, real-time configuration of radio functionalities, such as transmit power, receiver gain, carrier frequency, channel bandwidth and others result in a modular software defined radio platform. © 2012 ICST Institute for Computer Science, Social Informatics and Telecommunications Engineering.