User manual
GTR64  http://www.matrix.es/GTR64 
Voice Features 
Telephony 
Emergency calls 
Full Rate, Enhanced Full Rate, Half Rate and Adaptive 
Multi-rate (FR/EFR/HR/AMR) 
Noise suppression and echo cancellation 
Sidetone/microphone amplification 
Short Message Service (SMS) Features 
Text and PDU 
Point to point (MT/MO) 
Cell Broadcast 
Internet Protocols 
TCP/UDP/IP protocol stack 
Extensive AT command access to TCP/IP stack 
Multi sockets (up to 15) through AT commands 
Non blocking listening/server capability 
IPv4 protocol 
Dynamic & static IP address allocation 
PPP protocol (PAP) 
Embedded Application 
Multiple UART access 
Embedded script interpreter 
Extensive API library 
Embedded application script downloads over the air 
using GPRS 
1.3 GTR-64 Wireless modems in a Communication System 
Figure 1 and Figure 2 illustrate the main blocks of a wireless communication system using the wireless 
modem. Figure 1 shows the communication system when a micro-controller is used. They also show the 
communication principles of the system and the interface between the wireless modem and the 
application and Figure 2 shows the communication system when the script is embedded on the wireless 
modem. The definitions in the figures, as used elsewhere in this manual, are in accordance with the 
recommendations of 3GPP TS 27.007. 
The MS (mobile station) represents the wireless modem and SIM card. The wireless modem excluding 
SIM card, is known as the ME (mobile equipment). 
The DTE (data terminal equipment) is the controlling application. This can be either an external host or 
an internal embedded application. 
The DCE (data circuit terminating equipment) is the serial communication interface of the MS. 
GTR64 Integrators Manual V.1.2  Pag. 7 
Preliminary. Subject to change without prior notice 










