GRIN dielectric lenses/antennas have been a hot topic of research for virtually every microwave/mmWave application, from military/defense, aerospace/space, to commercial telecommunications. There have even been several companies, products, and government/DoD grants using GRIN dielectric lens/antenna technology. This article provides some discussion around recent research (since 2018) on GRIN dielectric lenses/antennas, and an overview of GRIN dielectric lenses/antennas being deployed or intended for practical use.
