JR山手線の車両内を5G（ミリ波）エリア化する実証に成功
KDDIとJR東日本は、山手線の車両内に5Gミリ波エリアを構築する実証実験に成功しました。窓のガラスアンテナで受信した電波を車内に再放射することで、1Gbpsの通信が可能なエリアが車両全体の約40%から約97%へと大幅に改善されました。
📋 記事の処理履歴
- 📰 発表: 2026年5月20日 23:00
- 🔍 収集: 2026年5月20日 14:31
- 🤖 AI分析完了: 2026年5月22日 14:04（収集から47時間32分後）
よくある質問
What was the main achievement of this demonstration?
The successful creation of a stable, high-speed 5G millimeter-wave (mmWave) communication area inside a JR Yamanote Line train car, a challenging environment due to the signal-blocking metal structure.
How did the technology bring the 5G signal into the train?
It used a mmWave-compatible glass antenna on the train's window to receive the signal from a trackside base station. The signal was then amplified and re-radiated throughout the car using a dielectric waveguide and other antennas.
By how much did the 5G coverage inside the train improve?
The communication area capable of achieving speeds of 1Gbps was improved from approximately 40% of the vehicle to about 97%.
Which companies were involved in this project?
The demonstration was led by KDDI and JR East, with technological cooperation from AGC, Nippon Dengyo Kosaku, and Kyocera.
Why is it difficult to get a 5G mmWave signal inside a train?
5G mmWave signals have high directivity and are easily blocked by obstacles. The metal body of a train car acts as a shield, making it very difficult for the signal to penetrate from the outside.