Xircom An Intel Company GEM3501 User Manual
Core Engine GSM/GPRS Modem Developer Guide Preliminary Draft: 7/6/2001
56
Part Number: 07100026, Revision: 002
Confidential
© 2001 Xircom, Inc., an Intel company All rights reserved.
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
All trademarks and copyrights are the property of Xircom, Inc., an Intel company
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There are a number of antennas designed for use with the Core Engine modem. If
coverage is poor then the use of a remote antenna may be required. Ideally, the external
antenna is mounted on a rooftop, or on the side of a building where optimal signal
strength can be obtained.
coverage is poor then the use of a remote antenna may be required. Ideally, the external
antenna is mounted on a rooftop, or on the side of a building where optimal signal
strength can be obtained.
15.1 Antenna Coaxial Cable and Connectors
In most cases RG223 50 ohms or similar small diameter cable can be used. For outdoor
installations, the coaxial cable must be rated for outdoor exposure.
installations, the coaxial cable must be rated for outdoor exposure.
For either fixed or mobile applications, if the antenna has less than a 3 dB gain and a
separation distance of greater than 20 cm (7 7/8 inches) from the body of the antenna,
and any nearby person(s), then the installation will comply with current FCC requirements
addressing human exposure to radio frequency electromagnetic fields.
separation distance of greater than 20 cm (7 7/8 inches) from the body of the antenna,
and any nearby person(s), then the installation will comply with current FCC requirements
addressing human exposure to radio frequency electromagnetic fields.
NOTE: The installer is responsible for assuring that the proper antenna is installed
so that the above limits are not exceeded.
so that the above limits are not exceeded.
15.2 Outdoor Antenna Grounding
Any outdoor antenna used to transmit or receive RF signals and the antenna connecting
cables must be properly grounded to comply with the National Electrical Code (NEC) -
specifically, but not limited to, articles 250, 800, 810, 820.
cables must be properly grounded to comply with the National Electrical Code (NEC) -
specifically, but not limited to, articles 250, 800, 810, 820.
Codes require proper grounding of the cables at the point where they enter a building.
Local building codes may also be applicable. For clarification on either local or national
grounding requirements, contact the state or county inspection officials in your location.
Local building codes may also be applicable. For clarification on either local or national
grounding requirements, contact the state or county inspection officials in your location.
15.3 Coaxial Cable Routing
When surveying a site for external antenna installation, verify that there is a suitable path
for the antenna cable from the antenna to the RF antenna connector on the modem. The
coaxial cable must be supported along its path, and protected to assure that damage
does not occur.
for the antenna cable from the antenna to the RF antenna connector on the modem. The
coaxial cable must be supported along its path, and protected to assure that damage
does not occur.
NOTE: All cables require routing to be free from any obstacles or any other type of
interference that may cause the cable to be damaged or undergo later damage to
the shielding or cable casing.
interference that may cause the cable to be damaged or undergo later damage to
the shielding or cable casing.
Installation of the cables should be in accordance with the manufacturer’s instructions, the
National Electrical Code, applicable building codes, and general industry standards and
National Electrical Code, applicable building codes, and general industry standards and