Design of flexible radio unit for distributed antenna systems

Distributed antenna systems (DAS) are one of good solutions to demands of the rapidly increasing data traffic and reduce the system complexity and manage the cellular mobile communication system more efficiently. DAS consist of base band unit (BBU) and remote radio heads (RRHs). BBU and RRHs connected through a fiber optic cable which is still expensive. In this paper, the modular radio units (RUs) are proposed to various services and which can be installed in various environments. The modular RU is consisting of an interface, transceiver, power amplifier, and antenna module and able to 2 × 2 MIMO functions. The size of modular RU is 80mm×80mm×100mm (W×D×H) except an interface module. Each module is implemented and the performance was measured.