A dual-antenna phase-array ultra-wideband CMOS transceiver

Ultra-wideband (UWB) systems use high-bandwidth signals to enable a new generation of ultra-high-data-rate wireless applications. Implementation of a high-bandwidth RF system in the 3-5 GHz band presents challenges that can be solved by circuit and system techniques. This article looks at the motivation and requirements for a WiMedia-compliant UWB system implemented for a target application in wireless video transmission. It explores the circuit-level trade-offs in CMOS radio and some of the system-level methods, such as selection diversity and equal-gain combining, used to increase robustness in multipath and interference environments. The radio (S. Lo, 2006) is part of a two-chip solution that includes a digital baseband chip that implements the WiMedia-compliant PHY and MAC. The measured results of the 0.18 mum CMOS UWB transceiver demonstrate the efficacy of these techniques in the final RF and system performance