Question Can you give me a brief explanation on the difference between GSM-traffic and GSM-R traffic, and would it be possible to tell me where I can find some more indeep info on this toppic please ? (equipments, protocols, physical layers, etc ...) - Tx a million
Answer Hello, Danny.
GSM is short for Global System for Mobile communications, one of the leading digital cellular systems. GSM uses narrowband TDMA, which allows eight simultaneous calls on the same radio frequency. GSM was first introduced in 1991, GSM service are widely available in most countries and has become the de facto standard in Europe and Asia
GSM is the global standard for mobile telephone as described in the ITU UMTS standards, GSM-R is just the same standards and protocols specially tailored to Railway applications with high-speed mobility and specially adapted propagation characteristics for application when a train should pass trough a length underground tunnel.
GSM-R is specifically designed for various railway applications, such as communication between pilot and traffic control with selective and direct mode, internal train communications for train staff, shunting, and maintenance teams along the track.
Shunting mode
Shunting mode is the term used to describe the application that will regulate and control user access, shunting communications is basically a link assurance signal that is provided in order to give reassurance to the driver that the radio link is working.
Direct mode
Direct mode is the walkie-talkie mode (mobiles station talking to each other without the network) and has been proposed in Eirene, however it has never been in application since being based on analogue radio.
In some industry claims to have developed a GSM direct mode, not currently recognized in the GSM-R specification, and has no frequency allocation.
The best source of information would be the ITU and UMTS Documents, which states the frequency and protocol standards as well as many relevant information covering GSM and GSM-R
