UC San Diego

The millimeter-wave (mm-wave) spectrum is currently used for the fifth-generation (5G) standard for high data-rate and low-latency links for both mobile users and fixed wireless access. The 5G standard supports licensed bands at 23.5-30.5 GHz and 37-43 GHz and unlicensed band at 57-71 GHz. Compared with 4G bands, the mm-wave bands support 10× larger bandwidth and thus can greatly improve the data-rate and maximize the throughput. At millimeter-wave frequencies, phased-array antennas with 32 to 512 elements are used to increase the antenna directivity so as to overcome the severe path loss. Such arrays can improve the link margin and allow for Gbps communications at 50-1000 meters. The research projects in this dissertation, in consequence, focus on the design and implementation of wideband 5G phased-arrays at 28 GHz and 39 GHz with 64 to 256 elements and with state-of-the-art performance. Also, the phased array system analysis for EVM degradation versus RMS error, and advanced applications such as carrier aggregation at mm-waves are investigated.