Trimble Inc. TRIMTRAC1 Benutzerhandbuch
DRAFT TrimTrac Locator Technical Manual 8
Global System for Mobile Communications
Cellular mobile telephone systems are widely available throughout the world.
However, because cellular mobile telephone systems are regulated at the national
level, these systems are not generally compatible with each other. To resolve the
dilemma of being able to communicate from almost anywhere, but only within
your own system, the European telecommunications operators—the Conference
of European Postal and Telecommunications Administration (CEPT)—designed a
new mobile telephone network.
However, because cellular mobile telephone systems are regulated at the national
level, these systems are not generally compatible with each other. To resolve the
dilemma of being able to communicate from almost anywhere, but only within
your own system, the European telecommunications operators—the Conference
of European Postal and Telecommunications Administration (CEPT)—designed a
new mobile telephone network.
This network has evolved into GSM, and CEPT has turned over management of
GSM to the European Technical Standards Institute (ETSI). GSM is the
predominant mobile communications system throughout the world. Outside the
United States, most GSM systems operate at 900 MHz, 1800 MHz or both and
services provided by these networks are generally referred to as Digital
Communication Services (DCS). The United States GSM system operates at 1900
MHz and is generally referred to as Personal Communication Service (PCS).
GSM to the European Technical Standards Institute (ETSI). GSM is the
predominant mobile communications system throughout the world. Outside the
United States, most GSM systems operate at 900 MHz, 1800 MHz or both and
services provided by these networks are generally referred to as Digital
Communication Services (DCS). The United States GSM system operates at 1900
MHz and is generally referred to as Personal Communication Service (PCS).
GSM Cellular Phone System
The Global System for Mobile (GSM) protocol offers a variety of data services
that allow users to send and receive data at rates of up to 9600 bps. Data can be
delivered over ISDN, Packet Switched or Circuit Switched Data Networks (PSDN
or CSDN) and via the Short Message Service (SMS). The TrimTrac locator uses
SMS, which is a store-and-forward service for the bi-directional exchange of
alphanumeric messages of up to 160 characters.
that allow users to send and receive data at rates of up to 9600 bps. Data can be
delivered over ISDN, Packet Switched or Circuit Switched Data Networks (PSDN
or CSDN) and via the Short Message Service (SMS). The TrimTrac locator uses
SMS, which is a store-and-forward service for the bi-directional exchange of
alphanumeric messages of up to 160 characters.
Architecture of the GSM network
Any asset tracking or management system on GSM consists of several distinct
components. The TrimTrac locator is the mobile unit that is installed in the
vehicle, equipment or other mobile asset and contains the Subscriber Identity
Module (SIM). The SIM card contains a unique International Mobile Subscriber
Identity (IMSI) number. This enables the network to identify the user and
therefore allow the terminal to have access to specific, subscriber services.
components. The TrimTrac locator is the mobile unit that is installed in the
vehicle, equipment or other mobile asset and contains the Subscriber Identity
Module (SIM). The SIM card contains a unique International Mobile Subscriber
Identity (IMSI) number. This enables the network to identify the user and
therefore allow the terminal to have access to specific, subscriber services.