We have looked at glass-based connectivity solutions a few times on this blog, especially the work around transparent antennas and the use of windows as part of the radio network. The idea may sound futuristic, but it is gradually moving from concept demonstrations to more practical deployment scenarios. The latest example comes from KDDI and JR East, who have successfully demonstrated a way to expand 5G millimetre wave coverage inside JR Yamanote Line train cars. The demonstration was completed by 15 April 2026 at JR East’s Tokyo General Rolling Stock Center, with the news release published on 20 May 2026. The train cars used for the test were parked, so this should be seen as an important technical demonstration rather than a live passenger service deployment. The challenge being addressed is easy to understand. The 28 GHz band used for 5G millimetre wave can provide high-speed, high-capacity connectivity, but it is also highly directional and more easily blocked by obstacles. Train...
2G, 3G, 4G, 5G, 6G, Wi-Fi, IoT, Bluetooth, LoRaWAN, Sigfox, Satellites