LZT 123 1834 14
2.3 Features
The wireless modem performs a set of telecom services (TS) according to 3GPP
release 99 and ITU-T. The functions of the wireless modem are implemented by
issuing AT commands over a serial interface.
2.3.1 Types of Mobile Station
The GR64 is a fully Quad Band capable GSM/GPRS mobile station with the
characteristics shown in the table below.
Feature GSM850 E-GSM900 GSM1800 GSM1900
Tx 824-849 880-915 1710-1785 1850-1910
Frequency range (MHz)
Rx 869-894 925-960 1805-1880 1930-1990
Channel spacing 200kHz 200kHz 200kHz 200kHz
Number of channels 124 174 374 299
Number of TD slots 8 8 8 8
Duplex spacing 45MHz 45MHz 95MHz 80MHz
GSM power class 4 (2W) 4 (2W) 1 (1W) 1 (1W)
Modulation GMSK
Receive sensitivity <-102dBm at antenna connector
GPRS multi-slot class Class 10
2.3.2 Short Message Service
The wireless modem supports the following SMS services:
• Sending; MO (mobile-originated) with both PDU (protocol data unit) and text
mode supported
• Receiving; MT (mobile-terminated) with both PDU and text mode supported
• CBM (cell broadcast message); a service in which a message is sent to all
subscribers located in one or more specific cells in the GSM network (for example,
traffic reports)
• SMS status report according to 3GPP TS 23.40
The maximum length of a text mode SMS message is 160 characters using 7-bit
encoding. The wireless modem supports up to six concatenated messages to extend
this function. Concatenation is performed by the host application.
