UC Irvine

In this dissertation, low-power blocks in UWB transceiver systems are presented. In particular, the main focus of this study is how low-power blocks in an impulse radio UWB (IR-UWB) system can be employed in sensor networks such as Body Area Networks (BANs).

The thesis is divided into three general parts. In the first part, the general history, definitions, regulations, and development of UWB systems are reviewed. In addition, a brief explanation of the fundamental concepts of radio frequency communication in short duration of pulses is given.

In the second part, the startup behavior of LC-VCOs used in UWB transmitters is investigated. In order to decrease the power consumption of the circuits without adding any complexity, we deliberately introduce a small asymmetry into the VCO that can greatly reduce the oscillation start-up time.

Finally, we study the super-regenerative receiver architecture and the challenges it presents. In this work, we have designed a low-power 4 Mb/s super-regenerative receiver in a 0.18 µm CMOS process that tracks the incoming signal carrier pulse and synchronizes it with a pulse quench signal. The energy consumption for this receiver is 0.17 nJ/bit, which demonstrates the lowest energy consumption reported so far for an IR-UWB receiver system.