Dec 5 (Fri) @ 2:30pm: "Towards Deployable mmWave Networks: Robust LoS MIMO and Distributed Radar," Lalitha Giridhar, ECE PhD Defense

Location: Engineering Science Bldg (ESB), Room 2001
Zoom Meeting: https://ucsb.zoom.us/j/89075474343?pwd=y0tEyjD3WYfwxbLwy6r02X6PiIf0Ul.1
Research Area: Communications & Signal Processing, Computer Engineering
Research Keywords: Wireless Communication, Digital Signal Processing, Distributed Radar, mmWave Comm Systems

Abstract

Reliable millimeter-wave (mmWave) systems require architectures that remain robust under real-world geometric uncertainties and can flexibly leverage distributed sensing. This dissertation advances this goal by developing resilient line-of-sight multiple-input multiple-output (LoS MIMO) communication strategies and a practical framework for using distributed radar networks to extract one-shot position and velocity information for a moving target. Together, these contributions move toward deployable, geometry-aware mmWave networks.

The first thrust introduces SOAR (Spatially Oversampled Adaptive Reception), a design that combines receive-side spatial oversampling with adaptive space–time equalization to mitigate misalignment and link-range variations in short-range LoS MIMO front-, mid-, and backhaul links. For long-range operation, the use of reflect-arrays is explored to form large virtual apertures that restore spatial degrees of freedom while preserving compact, power-efficient hardware, enabling multi-Gbps LoS MIMO communication over kilometer scales.

The second thrust presents mmSnap, a framework for self-calibrated distributed mmWave radar that transforms opportunistically deployed COTS nodes into a coherent sensing network. A closed-form calibration method determines relative poses from aligned target tracks, and a Bayesian one-shot fusion scheme provides instantaneous position and velocity estimates, demonstrating a practical pipeline for extracting actionable information from distributed radar measurements.

Bio

Lalitha Giridhar is a Ph.D. candidate with a background in wireless systems and signal processing. After completing her B.Tech at VIT Chennai in Chennai, India, she pursued graduate studies at UCSB, where her work centers on mmWave communication, distributed radar, and hardware-aware system design. She is broadly interested in building systems that connect mathematical structure with practical constraints and enjoys working across theory, simulation, and real-world experimentation.

Hosted By: ECE Professor Upamanyu Madhow

Submitted By: Lalitha Giridhar <lalitha@ucsb.edu>