UC San Diego

The inevitable growth of mobile users and the proliferation of data-intensive applications are creating unprecedented challenges and opportunities. Therefore, the deployment of the fifth generation (5G) networks worldwide is accelerating to meet the increasing data-rate demands. Several mm-wave bands have been standardized as part of the 5G new radio frequency range 2 (NR FR2) at 24.25-52.4 GHz. The dissertation addresses the challenges of designing mm-waves ultra-wideband circuits and phased-array systems capable of operating at this widespread spectrum in advanced SiGe technology. The major contributions are the design of receive (Rx), transmit (Tx), and Tx/Rx beamformer chips and the implementation of multi-band 8×1 linear phased-array modules and large-scale 64-element phased array systems.

The work in the 15-57 GHz Rx 4×1 beamformer culminated in the design and measurement of ultra-wide-band LNA, phase shifter, VGA, differential to single-ended stage and 4:1 on chip combining network with >40 GHz of bandwidth. Several circuit design techniques are introduced to break the gain-bandwidth (GBW) trade-offs in conventional beamformer designs. A peak electronic gain of 24-25 dB and a 4.7-6.2 dB noise figure is achieved with a 15-57 GHz record 3-dB bandwidth.

The mm-wave multi-band transmit phased-array contributions focus on the design of 16-52 GHz 4×1 transmit beamformer chip. The Tx IC has four differential RF beamforming channels each with an active balun, vector modulator based phase shiftier, VGA, and a 2-stage class-AB power amplifier (PA). Circuit techniques employed in this work are selected to fulfill the power and bandwidth requirements with compact area utilization. An 8-element phased-array Tx module is demonstrated achieving broadband performance with +/- 60 degrees scanning capability.

The work in the 64-element multi-band transmit and receive phased arrays employs the slat-array architecture using 16×1 linear arrays each has four 4×1 beamformer chips and end-fire tapered-slot antennas. Architecture and system analysis are presented to realize 16-52 GHz multi-standard operation. The 64-element Tx array achieves an EIRP of 50-51.7 dBm and 47.6-49 dBm at Psat and P1dB, respectively, at 24.5-48 GHz.