From windows to base stations

14 November 2024

JTower recently announced the deployment of a new glass antenna, created with glassmaker AGC and NTT Docomo.

The first was installed on a window in Tokyo’s Shinjuku district, and, according to Shota Ochiai, a marketing manager at AGC, is “the world’s first antenna that turns a window into a base station that can be attached to a building window inside and turn the outdoors into a service area without spoiling the cityscape or the exterior appearance of the building.”

5G networks, lauded for their high-speed low latency capabilities, require many more base stations than older generations of mobile networks to achieve the same coverage. Accordingly, to expand 5G footprint without installing unsightly equipment, Japanese companies are now developing transparent glass antennas that allow windows to serve as base stations that can be shared by several carriers.

NTT Docomo uses transparent conductive materials as the basis for its antenna, sandwiching the conductive material along with a transparent resin, in between two sheets of glass. The WAVEANTENNA antenna can be engineered according to the thickness of the glass to reduce the attenuation and reflection of the radio signals being absorbed and emitted.

“The glass antenna uses our proprietary technology to smooth out the disruption in the direction of radio waves when they pass through a window,” added Ochiai.

Compatible with frequencies in the sub-6GHz band, the WAVEANTENNA’s lower frequency ranges penetrate walls and buildings better than the higher bandwidth mmWave portions of the 5G spectrum. As such, these next-generation glass antennas could prove a real boon to expanding 5G coverage, particularly within dense urban regions, especially amidst growing infrastructure sharing.

“I don’t think the idea for using transparent conductive materials as an antenna existed before,” said AGC’s general manager Kentaro Oka. “The durability of the antenna was significantly increased by placing the conductive materials between glass.”