A 1.9–2.6 GHz router switch IC for MIMO applications in 0.18 μm CMOS technology

In MIMO applications, beam forming and spatial diversity are two possible solutions to enhance system performance. To operate in these two scenarios with a utility hardware, the function of reconfiguration is required. In beam forming, power combining and power splitting are needed in receiver and transmitter respectively. In spatial diversity, signal from each antenna are processed by RF paths and basebands separately to against the fading distortions. In this work, a router switch implemented in 0.18 μm CMOS for 2×2 MIMO is proposed. The proposed router switch can be configured to provide three operation modes, which are power combining mode, power splitting mode, and power paralleling mode. It provides a flexible interface between RF front-end and transceiver chip in MIMO systems.