751-3 Railway Communication System Basics

This page covers the basics of the 751-3 system, used as a railway communication system. In Europe, track-to-train mobile communication systems were initially based on the UIC standard, specifically 751-3, issued in 1970.

The 751-3 system supports both voice and data message communication. Short data messages can be transmitted using 2-tone FSK modulation. In this system, specific frequencies are assigned to different geographical areas. As a mobile device enters a new area, it automatically switches to the assigned frequency for that region.

Any mobile device can transmit on the channel, and any device in the nearby area can listen.

Here are the key features of the 751-3 railway communication system:

• Technology: Analog FM
• Frequency: 460 MHz
• Effective Bandwidth: 25KHz (per voice channel)
• Call Setup Time: Less than 1 second
• Call Features: Supports group calls and emergency calls.
• WAN Support: No WAN support.
• Security: Roaming, authentication, and encryption are not supported.
• Handover: Limited handover is supported.