We have looked at several approaches to improving millimetre-wave (mmWave) connectivity on this blog, including transparent antennas, metasurfaces and, more recently, KDDI and JR East's demonstration of bringing 28 GHz signals inside railway carriages. While these technologies address challenges such as signal penetration and coverage, another important problem is maintaining stable connectivity when vehicles are moving between different antenna coverage areas. This is something that NTT DOCOMO, NEC and NTT have been investigating through their work on distributed MIMO (Multiple-Input Multiple-Output) technology. In May 2026, NTT DOCOMO and NEC, in collaboration with NTT, announced the successful demonstration of a technique that allows multiple vehicles travelling at speed to maintain more stable, high-capacity wireless communications using the 40 GHz mmWave band. The work builds on their earlier research and is being positioned as an important step towards future 6G application...
High Altitude Platform Stations, or HAPS, are often described rather simply as "flying base stations". The idea is to place a communications platform in the stratosphere, typically around 20 km above the Earth, where it can provide mobile coverage across a much larger area than a conventional terrestrial base station. SoftBank's latest HAPS trials in Japan suggest that this description may increasingly undersell what these platforms could eventually do. In August 2026, SoftBank and US-based Sceye conducted a series of HAPS communications trials off Cape Muroto in Kochi Prefecture. The tests included conventional smartphone connectivity, communications with drones and, perhaps most interestingly, edge computing performed directly aboard the HAPS. SoftBank sees these capabilities eventually becoming part of a three-dimensional communications network integrating terrestrial networks, HAPS and satellites. The platform itself was Sceye's lighter-than-air, or LTA, HAPS. U...