Chapter 1 – Description & Specifications
Multi-Tech Systems, Inc. MultiModem® GPRS with USB User Guide 6
GSM 850
Frequency RX 869 to 894 MHz
Frequency TX 824 to 849 MHz
RF Power Stand 2W at 12.5% duty cycle
Impedance 50 ohms
VSWR <2
Typical Radiated Gain 0 dBi on azimuth plane
GSM 1800 GSM 1900
Frequency RX 1805 to 1880 MHz 1930 to 1990 MHz
Frequency TX 1710 to 1785 MHz 1850 to 1910 MHz
RF Power Stand 1W at 12.5% duty cycle 1W at 12.5% duty cycle
Impedance 50 ohms
VSWR <2
Typical Radiated Gain 0 dBi on azimuth plane
AT commands for the GPRS wireless modem are published in a separate Reference Guide
included on the product CD and posted on the Multi-Tech web site.
IP commands for GPRS modems are also published in a separate Reference Guide included
on the product CD and posted on the Multi-Tech web site.
Phone Number for the Wireless Modem • Every wireless modem will have its own unique phone number.
• The wireless modem’s phone number may simply be told to the subscriber or be on the
SIM or both. Wireless provider implementations may vary.
Network Access The network access arrangements to be specified in Windows Dial-Up Networking (of the
computer that the wireless modem is serving) will vary according to the type of wireless service
used.
• For GSM-without-GPRS, a circuit-switched data connection is used. The user can set up
DUN to make a conventional V.32 modem connection to any terminating modem at the
other end. The phone number specified in DUN can be one supplied by the wireless
service provider or another phone number related to a different dialup modem service
(e.g., a dialup modem service phone number from any commercial or private dialup
network).
• For GSM-with-GPRS, a single DUN number is generally used by all of a wireless provider’s
subscribers throughout its area of coverage (regional, nationwide, continental, etc.).
Rather than being a literal phone directory number, as in conventional DUN, this is a code
that gives the modem Internet access. Normally, this phone number is *99***1# .