Appendix B – Sources for Peripheral Devices
20
Appendix B – Sources for Peripheral
Devices
GSM Antenna
The integrated modem antenna connector is a MMCX connector. The MMCX connector incorporates a
'Snap On' latching action in order to make the connection easier with an excellent RF performance. An
additional advantage is its small physical size, which is 50% of the standard MCX connector.
This type of connector is suitable for the standard ranges of flexible and semi-rigid cables. The
characteristic impedance of the MMCX coaxial connector is 50 ohm. The antenna manufacturer must
guarantee that the antenna will be working according to the radio characteristics presented in the table
below.
Radio Characteristics
GSM 850
EGSM 900
GSM 1800
GSM 1900
Frequency RX
869 to 894 MHz
925 to 960 MHz
1805 to 1880 MHz 1930 to 1990 MHz
Frequency TX
824 to 849 MHz
880 to 915 MHz
1710 to 1785 MHz 1850 to 1910 MHz
RF Power
Stand
2W at 12.5% duty
cycle
2W at 12.5%
duty cycle
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
MMCX Plug
The SocketModem requires an MMCX plug to connect to an antenna.
MMCX Connector Example (right angle type)
Antenna
An antenna with matting connector can be ordered, for example, from:
IMS Connectors Systems GMBH
http://www.imscs.com/
MMCX / SMA Adapter
A small MMCX / SMA adapter can be ordered, for example, from:
Amphenol
http://www.amphenol.com/
Order No: 908-31100