Event Details

October 30, 2026

Join Zoom Webinar

Host: Steve Crago
POC: Amy Kasmir

Optical beams can be “structured” so that they can have unique amplitude and phase spatial distribution in the transverse X-Y plane at any given distance. This is exemplified by a beam being composed of one or more orthogonal spatial modes from a modal basis set, such as Laguerre Gaussian modes. Moreover, beams can be structured in the longitudinal direction along the propagation path, such that a beam can be tailored to exhibit various properties at different distances. This can be achieved by manipulating the longitudinal wavenumber of Bessel beams. Importantly, the above structuring can be applied to electromagnetic waves at other frequencies, such as millimeter and THz beams.

This presentation will highlight applications of beam structuring to communication and sensing systems. Topics will include:

(1) Communications: Capacity can be increased by multiplexing data-carrying beams that are on orthogonal modes, efficiency can be increased by encoding each bit on a mode from a larger set, and physical-layer security can be enhanced by simultaneously transmitting a data and a noise beam such that the noise is diminished only at the intended receiver’s location. These functions can be achieved at optical and RF frequencies. Moreover, degrading effects of turbulence and possible mitigation approaches will be discussed. (2) Sensing: Since a beam can be structured to have controllable parameters at different longitudinal distances (e.g., beam waist, spatial mode, polarization), atmospheric turbulence strength can be probed as a function of distance by varying the location of a narrow-waisted probe beam. Furthermore, accurate ranging can be achieved in underwater environments by measuring the beam’s features that evolve with propagation distance.

Speaker Bio

Alan Willner received a Ph.D. (1988) from Columbia University, as well as a B.A. (1982) and Honorary Doctorate (2012) from Yeshiva University. He has worked at AT&T Bell Labs and Bellcore, and is a Distinguished Professor and the Andrew & Erna Viterbi Professorial Chair at the Univ. of Southern California. His honors include: Member of US National Academy of Engineering; Int'l Fellow of UK Royal Academy of Eng; IEEE Eric Sumner Technical Field Award; NSF Presidential Faculty Fellows Award from White House; Fulbright, Guggenheim, Packard, and US DoD Vannevar Bush Faculty Fellowships; Thomas Egleston Medal from Columbia Eng. Alumni Association; IET JJ Thompson Medal; Ellis Island Medal of Honor; Optica Forman Eng. Excellence Award; IEEE Photonics Society Eng. Achievement Award; Eddy Best Technical Paper Award; Fellow of the National Academy of Inventors; and SPIE President’s Award. His activities include: Co-Chair of U.S. National Academies Study on Optics & Photonics; President of Optica and of IEEE Photonics Society; Editor-in-Chief of Optics Letters, IEEE/OSA J. of Lightwave Technology, and IEEE J. of Selected Topics in Quantum Electronics; Chair of National Photonics Initiative; and Member of the US Army Science Board and the Defense Sciences Research Council. He is a Fellow of AAAS, IEEE, IET, Optica, and SPIE. His research is primarily in optical communications, sensing, and signal processing.