{"693797":{"#nid":"693797","#data":{"type":"event","title":"PhD Defense by Alex Saad-Falcon","body":[{"value":"\u003Cp\u003ETitle: Adaptive Subspace Tracking and Inverse Design for High-Dimensional Electromagnetics\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EDate: Thursday, November 19, 2026\u003C\/p\u003E\u003Cp\u003ETime: 2:00 PM EST\u003C\/p\u003E\u003Cp\u003ELocation:\u003C\/p\u003E\u003Cp\u003EIn person: CODA C1015 (Vinings)\u003C\/p\u003E\u003Cp\u003EVirtual: \u003Ca href=\u0022https:\/\/teams.microsoft.com\/meet\/2420063874953443?p=zH2mKpDkLDTZuzvr7Q\u0022\u003Ehttps:\/\/teams.microsoft.com\/meet\/2420063874953443?p=zH2mKpDkLDTZuzvr7Q\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EAlex Saad-Falcon\u003C\/p\u003E\u003Cp\u003EMachine Learning PhD Student\u003C\/p\u003E\u003Cp\u003ESchool of Electrical and Computer Engineering\u003C\/p\u003E\u003Cp\u003EGeorgia Institute of Technology\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003ECommittee\u003C\/p\u003E\u003Col\u003E\u003Cli data-list-item-id=\u0022e8822b1f8847192446f68609d62b4c6d6\u0022\u003EDr. Justin Romberg (Advisor), School of Electrical and Computer Engineering, Georgia Institute of Technology\u003C\/li\u003E\u003Cli data-list-item-id=\u0022ee46f18fd53bea8da268de129bee2e6d8\u0022\u003EDr. Mark Davenport, School of Electrical and Computer Engineering, Georgia Institute of Technology\u003C\/li\u003E\u003Cli data-list-item-id=\u0022e2db7aa1a3cf0f8ecb9861ffa4a13cc16\u0022\u003EDr. Saibal Mukhopadhyay, School of Electrical and Computer Engineering, Georgia Institute of Technology\u003C\/li\u003E\u003Cli data-list-item-id=\u0022ed79062ef38d3050c5349d1847bdf7dd4\u0022\u003EDr. Nima Ghalichechian, School of Electrical and Computer Engineering, Georgia Institute of Technology\u003C\/li\u003E\u003Cli data-list-item-id=\u0022e436a337b45e5b5fe325d218d58a8fa4b\u0022\u003EDr. Ryan Westafer, Georgia Tech Research Institute\u003C\/li\u003E\u003C\/ol\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003EAbstract\u003C\/p\u003E\u003Cp\u003EThis dissertation develops theory, algorithms, and systems for high-dimensional optimization problems in electromagnetics. The first part studies subspace tracking and principal component analysis under hardware constraints such as limited computation, scarce memory, or acquisition restricted to a few linear measurements per sample. For Gaussian data in dimension d, it shows that an Oja-type algorithm using 2k adaptive linear measurements per sample estimates the top-k principal subspace at the minimax error rate of a two-level spiked model, up to a constant factor, when the sample size is known in advance, while measurement designs fixed in advance have a lower bound larger by a factor of order d\/k at large sample sizes when the (k+1)-th eigenvalue is comparable to the k-th. It also develops regularized least squares algorithms on the Grassmann manifold for tracking time-varying subspaces. On the systems side, it describes AdaAFE-CIM, which uses subspace tracking for adaptive data compression in array processing hardware and reduces baseband power by 95.4% relative to full digitization in power-model simulations, together with an open-source end-to-end simulator for array processing under realistic hardware and channel effects. Finally, it presents inverse design methods for electromagnetic structures: a periodic level set function for gradient-free topology optimization, validated by fabrication and measurement for metasurfaces, and a neural adjoint method for reconfigurable antennas with exponentially large switch configuration spaces.\u003C\/p\u003E","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EAdaptive Subspace Tracking and Inverse Design for High-Dimensional Electromagnetics\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Adaptive Subspace Tracking and Inverse Design for High-Dimensional Electromagnetics"}],"uid":"27707","created_gmt":"2026-11-05 13:33:34","changed_gmt":"2026-11-05 13:34:16","author":"Tatianna Richardson","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2026-11-19T14:00:00-05:00","event_time_end":"2026-11-19T17:00:00-05:00","event_time_end_last":"2026-11-19T17:00:00-05:00","gmt_time_start":"2026-11-19 19:00:00","gmt_time_end":"2026-11-19 22:00:00","gmt_time_end_last":"2026-11-19 22:00:00","rrule":null,"timezone":"America\/New_York"},"location":"CODA C1015 (Vinings)","extras":[],"groups":[{"id":"221981","name":"Graduate Studies"}],"categories":[],"keywords":[{"id":"100811","name":"Phd Defense"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1788","name":"Other\/Miscellaneous"}],"invited_audience":[{"id":"78771","name":"Public"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}