UC San Diego

Phased array technologies has been in development for many decades but primarily in defense industry with large complicated systems and excessively high cost. With the recent advances in silicon chips and printed-circuit board (PCB) manufacturing, planar phased arrays can be built on a PCB in a compact form with drastically lower cost. The new 5G communication standards also utilize millimeter wave bands that require phased arrays with high effective isotropic radiated power (EIRP) and beam steering capabilities. The 5G systems, with the fast growing industry of satellite communications on-the-move, and millimeter wave automotive radars used for self-driving technologies, contribute to a giant market in need of a large amount of low cost phased arrays. This dissertation focuses on such commercial-use phased arrays, studies their artifacts and how to eliminate them, provides solutions to optimized phased-array systems, and proposes calibration methods essential for their performance. First, it presents the intersymbol interference (ISI) caused by the phased array when it is scanned with a simple effective equalization scheme, and then, it presents a TX/RX phased-array system with a reduced number of randomly distributed elements that is optimized for radar applications. This dissertation also presents a new method for phased array calibration based on 2×2 sub-arrays that is more robust across different scan angles and yields better performance while reducing the measurement time. Finally, a method to measure the error vector magnitude (EVM) of the phased array in the near-field is presented, which can be used to verify the calibration and performance of phased arrays in communication systems when they are deployed in the field.