A thin column of air became the transmitting element in a radio experiment. Researchers fed a 30 MHz signal into a laser-induced plasma antenna, then measured what reached a nearby receiver. The surprising part was how they connected radio electronics to something no wire could safely touch.
North Carolina State University announced the work on October 5, 2026. The underlying paper appeared in the September issue of IEEE Journal of Microwaves, according to its research record. It reports a laboratory demonstration, not a deployed communications system.
How a laser-induced plasma antenna gets its signal
The laser ionizes a narrow path through air, creating a plasma filament. A surrounding metal ring acts as a capacitor: an applied radio-frequency signal produces an electromagnetic field that couples to the filament without direct contact. Touching it with metal would disturb it.
That arrangement gives the researchers a way to excite the plasma electrically. Changing laser parameters could also change the filament’s length; steering the beam could change its orientation. Those are proposed advantages of an antenna whose shape does not depend on mechanically extending a metal rod.
Five centimeters is the crucial detail
The study abstract hosted by Princeton University describes a receiver roughly five centimeters away, with matching polarization and an unobstructed near-field setup. With the laser blocked, the team measured the feed alone. With the filament present, received signal strength rose to about 2.5 times that baseline.
That comparison supports the filament’s contribution to the measured electromagnetic signal. It does not establish useful long-distance range, efficiency in a practical installation, or an advantage over a conventional antenna. The university also says reception using the plasma antenna itself has not been demonstrated.
What would make it useful?
The appeal is reconfiguration: an antenna whose geometry can follow a beam rather than a moving mechanism. Aircraft and satellites appear among the possible applications discussed by the researchers, but those possibilities remain prospective.
All three linked records describe the same study; they are not independent replications. Our assessment is that the next meaningful milestone would be performance measured under conditions closer to an actual radio link. Turning air into a transmitting element is an intriguing beginning. Making the complete apparatus worth carrying is the engineering challenge that follows.
