
3
Installation
GPS/GLONASS Receiver User Manual Rev 1
23
3.4.6 L1 GPS/GLONASS ANTENNA CONSIDERATIONS
The MiLLennium-GLONASS GPSCard has been designed to operate with the NovAtel 504 or 514 single-
frequency GPS/GLONASS antenna models. Though it is possible to operate with other single-frequency GPS/
GLONASS antennas, no guarantee is made that the MiLLennium-GLONASS GPSCard will meet its performance
specifications if a non-NovAtel antenna is used. For further information on GPS/GLONASS antenna systems and
extended length cable runs, contact NovAtel Customer Service.
The NovAtel L1 GPS/GLONASS antennas, models 504 and 514, are active antennas designed to operate at the
GPS and GLONASS L1 frequency. The 504 antenna is intended for surveying and other kinematic positioning
applications, and the 514 is an aviation antenna that is ideally suited for installation on aircraft. For more
information on the model 504 antenna please refer to the NovAtel L1 GPS/GLONASS Antenna Model 504 Brochure
(NovAtel part number OM-20000037), and for more information on the model 514 antenna please refer to the
NovAtel L1 GPS/GLONASS Antenna Model 514 Brochure (NovAtel part number OM-20000038).
When installing the antenna system,
•
choose an antenna location that has a clear view of the sky so that each satellite above the
horizon can be tracked without obstruction. (For a discussion on multipath, refer to the
relevant appendix in the MiLLennium Command Descriptions Manual.)
•
mount the antenna on a secure, stable structure capable of safe operation in the specific
environment.
3.4.6.1 Antenna Cable Considerations
An appropriate coaxial cable is one that is matched to the impedance of the antenna being used, and whose line
loss does not exceed the recommendations shown in Table 3.2, Page 23. NovAtel offers a variety of coaxial cables
to meet your single-frequency GPS/GLONASS antenna interconnection requirements. Your local NovAtel dealer
can advise you about your specific configuration.
NovAtel provides optional coaxial cables in the following lengths:
•
22 cm interconnect adapter cable (SMB female/TNC bulkhead - female; NovAtel part
number GPS-C001)
•
5, 15, or 30 m antenna cable (TNC male/TNC male; NovAtel part numbers C005, C015 and
C030 respectively)
Though it is possible to use other high-quality antenna cables, no warrant is made that the MiLLennium-
GLONASS GPSCard will meet its performance specifications if non-NovAtel-supplied coaxial cable is used.
Table 3.2 Recommended Maximum Cable Loss
NOTE:
The coaxial cable should be connected to the antenna and MiLLennium-GLONASS GPSCard before
system power is turned on. If for any reason the cable is disconnected from either the antenna or receiver,
you must turn off power before reconnecting the cable(s) otherwise the MiLLennium-GLONASS
GPSCard will not be able to sense the antenna and the system will not work. If this occurs, remove power
from the receiver, wait a few moments, and then apply it again.
Antenna Type
Allowable Cable Loss
Active
13.0 dB
Passive
1.5 dB