Technical Manual

1. INTRODUCTION
6
LZT 123 7607 R1B
1.3.2 Short Message Service
The GT47 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). This feature is network dependent.
• SMS STATUS REPORT according to GSM 03.40.
• SMS COMMAND according to GSM 03.40.
The maximum length of an SMS message is 160 characters when using 7-
bit encoding. For 8-bit data, the maximum length is 140 characters. The
GT47 supports up to 6 concatenated messages to extend this function.
1.3.3 Voice Services
The GT47 offers the capability of mobile originated and mobile
terminated voice calls, as well as supporting emergency calls. Multi-party,
call waiting and call divert features are available. Some of these features are
network-operator specific.
For the inter-connection of audio, the GT47 offers a balanced 4-wire
analogue interface.
DTMF (Dual Tone Multi Frequency) is supported.
The GT48 also supports the Adaptive Multi Rate (AMR) type of vocoder.
GT48 GSM 850 GSM 1900
Frequency Range (MHz) TX: 824-849
RX: 869-894
TX: 1850-1910
RX: 1930-1990
Channel spacing 200 kHz 200 kHz
Number of channels 124 carriers *8 time slots
GSM: channels 128 to 251
299 carriers *8 time slots
PCS: channels 512 to 810
Modulation GMSK GMSK
TX Phase Accuracy < 5º RMS phase error (burst) < 5º RMS phase error (burst)
Duplex spacing 45 MHz 80 MHz
Receiver sensitivity at
antenna connector
< –102 dBm < –102 dBm
Transmitter output power
at antenna connector
Class 4
2W (33 dBm)
Class 1
1 W (30 dBm)
Automatic hand-over between GSM 850 and GSM 1900