The Trend of Research and Development and International Standardization of Radio Communication Systems using Millimeter-waves in Railway

In railways, train radio systems have long been introduced as a means of communication between running trains and the ground. However, current train radio systems mainly use voice communication, and the amount of information that can be transmitted are limited. Therefore, researches are being carried out to realize the broadband ground-to-train radio communication using millimeter-waves. This paper reports that the trends of research and development toward the utilization of millimeter-waves in railways, the current status of international standardization activities, and future prospects.