UC San Diego

With the development of wireless communications, high data rate is becoming essential since it not only augments the current wireless systems but also enables many emerging applications. In order to achieve multi-gigabit-per-second data rates, the fifth generation communication system (5G) is moving forward to the millimeter-wave band, such as 24-29 GHz and 37-42 GHz. Since the frequency is more than 10 times than the current communication protocols, the wavelength is 10 times smaller, which makes the transmission line effects more notable and increases the design complexity. Moreover, the path loss is much larger and therefore a higher output power or antenna EIRP (effective isotropic radiated power) is required to overcome this loss. Previous millimeter-wave 5G research focused on narrow band, such as 28 GHz and 39 GHz. But if a single system can be wideband and include all of these bands, the simultaneous data rate can be increased and the system cost can be reduced. The research projects in this dissertation, in consequence, focus on different wideband RF ICs, and include power amplifiers (PA), low noise amplifiers (LNA), wideband phased-array receivers with high single-sideband rejection, wideband IQ receivers and wideband front-end circuits including phase-shifters and variable gain amplifiers. All of these circuits were done in advanced CMOS SOI technologies. The thesis concludes with a list of future work to be done in this area.