Researchers at Malaysia's Universiti Teknologi MARA used ionized gas in a common fluorescent light tube to create an antenna for a Wi-Fi Internet router, Phys.org reports.
The invention is designed to address a coverage problem. Pretty much everyone is familiar with Wi-Fi radio "dead spots," which can occur in areas where Wi-Fi is in high demand: conference centers where walls or appliances block a router's signal or degrade it so much that it becomes too weak for a tablet or phone to be used reliably.
The prototype antenna in question consists of a fluorescent tube that connects to the router through a tuned wire coil in a sleeve slipped over one end. The coil passes the router's radio signal through the glass of the fluorescent tube and into the plasma.
According to the Malaysian research team, the plasma found in a standard 62-centimeter light tube is highly conductive and signal measurements on a test device show that it's strong and stable, Phys.org says. It just so happens that plasma compares favorably with standard metal Wi-Fi antennas for transmitting and receiving.
Plasma has conducting properties comparable to a common metal radio antenna, allowing an attached router to send and receive radio signals through the light tube on the standard 2.4-gigahertz Wi-Fi frequency in the same way it does through a regular antenna. The router's radio waves can ionize the gas in the tube, so it acts as an antenna whether the light is on or off.
The report suggests that one possible application could involve installing the technology in outdoor billboard lights. Each plasma antenna array would then be integrated with a Wi-Fi router to provide large-scale, system-wide wireless communication.
There's no word on whether the technology or something akin to it would be considered for deployment in the U.S. Back in 2013, a common fluorescent light fixture in a hair salon in San Antonio, Texas, was identified as the source of interference for a nearby AT&T LTE cell site. An FCC agent used a spectrum analyzer and handheld antenna to confirm that the salon's overhead light fixture emanated a stray signal at 705 MHz, causing interference to AT&T's Band Class 17 LTE network.
- see this Phys.org article
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