Phased Arrays and Lenses for Low-Power 5G MMW Communications
Principal Investigator: Dr. Chisum, Department of Electrical Engineering
Project Summary: Phased arrays have proven to be an enabler for high-performance communications and sensing in the sub-6 GHz bands. They enable high-gain links to individual remote radios which can be tracked in space to achieve high data rates, enable spatial reuse, and even provide location-aware applications. This technology was initially developed in the defense sector at great cost and with significant power consumption. However, commercial-off-the-shelf (COTS) DACs and ADCs have seen a dramatic reduction in cost and power consumption and a wide range of integrated RF components in the sub-6 GHz bands have become available. These trends have enabled the technology to transition to the commercial sector with great success.
More recently the same technology was transitioned to the millimeter-wave (MMW) bands (>30 GHz) to enable 5G MMW communications with data rates beyond 1 Gbps. Unfortunately, the technology (data converters and radio components) did not scale well so the 5G MMW phased arrays consume extremely high power. In fact, the first generation of 5G MMW-enabled mobile phones were only capable of operating at Gbps rates for ~10 minutes before the battery was drained.
Instead of taking technologies that worked well at low-frequencies and moving them up in frequency, an alternative approach is to take technologies which natively work at high frequencies such as lens antennas, and modify them to provide the desired functionality (high-speed beam-scanning and multi-beam apertures) for 5G MMW.
The purpose of this research project: Is to explore the length to which switch-beam lens antennas can provide the most important features and capabilities of a phased array but at a fraction of the cost and power. This project will build off of the MMW lens antenna demonstrations from the PIs research group and will include theoretical electromagnetic antenna modeling as well as linear systems analysis (especially beam-forming theory and beam-synthesis methods from field theory). If tie permits the student will use the PI’s measurement laboratory and near-field antenna range to demonstrate phased-array-fed lens antennas using state-of-the-art beamformer integrated circuits.
Student’s Role: The student will survey the network requirements for a realistic MMW wireless network (e.g., 5G NR UWB), perform analysis and simulation of phased array and phased-array-fed lens systems, and determine what sort of feed architectures are necessary in order to support all necessary network functions of a base-station. This includes make-before-break connections, beam management (e.g., UE tracking), support for two separate UEs. The student will perform full-wave electromagnetic simulation of feed antennas and combine them with lens antenna models developed by the PI’s group. This work will use Matlab as well as Ansys HFSS. The work will be supported with guidance from graduate students and the PI.
By the end of the summer, the student will have applied electromagnetic theory and systems analysis to the question of low-power millimeter-wave beam-scanning antennas. The outcome of the work will be an assessment of how well lens antenna systems can accomplish the same thing as phased arrays at a fraction of the power and cost.