LTE-R:LTE-based Next-Generation Railway Wireless Communication System
LTE-R encompasses all the features of voice services (individual/group/emergency/priority calls and broadcasting), video services (video conferencing, CCTV train monitoring), and data (control signals, large-sized file transfer) services necessary for railway and public network operations.
- Voice communication among drivers, control center operators, maintenance and other railway staff supporting 1:1,
Push-to-Talk group communication, broadcasting, location-dependent addressing, and multi-level prioritization
- Data communication for the train control signaling and other operation and maintenance as well as
short message service (SMS) during voice communication.
- Multimedia communication for the wireless video surveillance, mobile video conference, large file sharing,
mobile office and passenger infotainment services.
Call Server provides 1:1 voice communication service. LTE-R supports high quality voice service even when user quipment is moving at high speed.
PTT Server provides Push-to-Talk service which has been supported by traditional train radio systems such as TETRA or GSM-R. PTT Server also supports short message services (SMS).
Conference Server supports multi-media group communication among multiple parties.
Operators in the control center can manage the train broadcasting system and provide broadcasting service for passengers by using LTE-R.
Emergency interphone calls by passengers on the train can be automatically connected to the drivers and operators in the control center via LTE-R.
Data & Multimedia Services
LTE-R provides the QoS (Quality of Service) needed for Train Control Signaling Communication. LTE-R can make Real-time Status Monitoring and Diagnostics of Train and Wayside Infrastructure Systems possible.
The real-time video of the CCTV cameras in the front and rear of the train can be sent to the operation control center via LTE-R.
The real-time CCTV video of passenger cabins can be sent to the operation control center to prevent and respond to emergency situations such as crimes, fires and accidents.
Real-time CCTV video of the level crossings can be sent to the drivers and/or control center operators to prevent accidents.
Video Conference Calls using handheld and other user terminals are supported by LTE-R.
- OCC (Operation Control Center)
LTER Functional Servers
- Call (VoIP or VoLTE) Server
- PTT (Push-to-Talk) Server
- Conference Server
- Command Server
- Video Server
- LTE Network
- PCRF (Policy and Charging Rule Function)
- S-GW (Serving Gateway)
- P-GW (Packet-Switched Data Network Gateway)
- MME (Mobility Management Entity)
- LCM-C/R (LTE System Manager for Core Network /
Radio Access Network)
- HSS (Home Subscriber Server)
- eNB (evolved Node B):
Remote Radio Unit
- LTER User Equipment
- Voice Call (VoIP or VoLTE)
- Push To Talk
- Short Message Service (SMS)
- Video Call
- Broadband Multimedia Service
- Mobile Office
Efficient Operation & Maintenance
It is no longer neccassary to build separate wireless communications systems dedicated to CCTV surveillance, signalling, or a specific data service. LTE-R supports voice, data, and video communication and can be easily integrated with other operational and management systems because it is an end-to-end IP-based system.
LTE-R will not only reduce costs for system building but also for operation and maintenance.
LTE-R can make the real-time status monitoring of train and wayside infrastructure systems possible by continuously connecting the train, wayside and Operation Control Center. The collected status data can be used for pre-analytics services to enhance the efficiency of the railway operation and maintenance.
Enhanced Passenger Experience
LTE-R can be used to provide real-time passenger information, e-ticketing and other multimedia infotainment services to enhance passenger satisfaction.
LTE-R system can support critical and priority communication services even when incoming calls and data traffic are overflowing.
LTE-R will allocate the necessary communication resources to those critical and priority services while adjusting the quality of the other less important communication services.
Drivers and Operation Control Center operators can monitor in real time the passenger cabins and/or platforms to prevent possible crimes or accidents and to immediately respond to emergency situations.
||LTE Standard||3GPP release 11|
|Duplex Scheme||FDD or TDD|
|Peak Downlink Speed||150 Mbps (for 20 MHz)|
|Peak Uplink Speed||50 Mbps (for 20 MHz)|
|Data Type||All packet-switched data (voice, data & video)|
|Frequencies Supported (Hz)||All 3GPP Standard Frequencies|
|FDD (700M, 800M, 850M, 1.8G, 1.9G, 2.1G, 2.6G, etc.)|
|TDD (2.3G, 2.5G, 3.5G, etc.)|
|Channel Bandwidth (MHz)||1.4, 3, 5, 10, 15, 20|
|Latency (ms)||Max. Connection Setup Time 500 msec|
|Access Schemes||OFDMA (Downlink)|
|Modulation for Downlink||QPSK, 16QAM, 64QAM|
|Modulation for Uplink||QPSK, 16QAM|
|Call Server||Functions||VoIP (Voice over IP) or VoLTE (Voice over LTE)|
|Operating System||Microsoft Windows 2008 Server|
|CPU||Intel Xeon X5570 (Quadcore, 2.93G/8M) x 2ea|
|Location-based Addressing, Short Message Service (SMS)|
|CPU||Intel Xeon X5570 (Quadcore, 2.93G/8M) x 2ea|
|Conference Server||Functions||Multi-media Group Communication|
|Operating System||Microsoft Windows 2008 Server R2|
|CPU||Intel Xeon X5540 (Quadcore, 2.53G) x 2ea|
|Command Server &
|Functions||User Data Management, Equipment Data Management,|
|User Group Management, User Equipment Status Monitoring,|
|Call History Management, Passenger Broadcasting Interface,|
|Passenger Emergency Interphone Interface|
|Command Console also supports LTE-R User Equipment functions|
|Operating System||Microsoft Windows|
|Functions||Voice (VoIP or VoLTE), PTT, Conference & SMS|
|CPU||Intel Atom(TM) DC N2600, 1 MB cache, 1.60 GHz|
|I/O||Receiver (Microphone Jack 3.5 mm)|
|Earphone (Phone Jack 3.5 mm)|
|HDMI (Display), UART, 10/100 LAN, USB2.0|
|Functions||Voice (VoIP or VoLTE), PTT, Video PTT, Conference, SMS & MMS|
|Operating System||Android Jellybean (Version 4.2.2)|
|CPU||SAMSUNG Exynos4412 (Quad-Core)|
|LCD||720 x 1280 dots (4.67˝, Touch screen)|
Samsung LTE-R system was tested on the Daebul and Honam Lines for 2 years and was certified for railway use in 2014.
- Tested Functions
- Voice, data and video service functions including Voice Call (VoIP), Push-to-Talk (PTT), Conference Call, Emergency Call, Wireless Broadcasting, Wireless CCTV Surveillance, Video Conference, Train Control Signaling Interface (QoS) and Inter-Frequency Handover between 700 MHz and 2.6 GHz. In the 5 MHz uplink and 5 MHz downlink frequency bandwidth environment, 10 Mbps uplink and 34 Mbps downlink peak data rates were available with 2x2 MIMO antennas.
Daebul (Test Line)
Length 12 km Stations 2 Train Type Urban Train Max. Train Sp eed 90 km/h RF Carrier Ban d 2.6 GHz Frequency Bandw idth 5 MHz(UL), 5 MHz(DL) Number of Digital U nits 2 Number of Radio U nits 10
Honam (Operational Line)
Length 54.2 km Stations 9 Train Ty pe Intercity Train Max. Train Sp eed 160 km/h RF Carrier B and 700 MHz Frequency Bandw idth 5 MHz(UL), 5 MHz(DL) Number of Digital U nits 7 Number of Radio U nits 52