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Successful Demonstration of 5G (Millimeter Wave) Area Coverage Inside JR Yamanote Line Train Cars

NQ Score 96/100

AI Summary (NQ-processed)

KDDI and JR East have successfully demonstrated a system to provide 5G millimeter-wave coverage inside a Yamanote Line train. By receiving signals with a glass antenna on the window and re-radiating them inside, the area capable of 1Gbps speeds was improved from 40% to 97% of the car.

AI Analysis

Frequently Asked Questions

Q: What was the main achievement of this demonstration?
A: 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.
Q: How did the technology bring the 5G signal into the train?
A: 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.
Q: By how much did the 5G coverage inside the train improve?
A: The communication area capable of achieving speeds of 1Gbps was improved from approximately 40% of the vehicle to about 97%.
Q: Which companies were involved in this project?
A: The demonstration was led by KDDI and JR East, with technological cooperation from AGC, Nippon Dengyo Kosaku, and Kyocera.
Q: Why is it difficult to get a 5G mmWave signal inside a train?
A: 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.