
Installation OEM6 Family Cards
Chapter 2
OEM6 Family Installation and Operation User Manual Rev 7
23
2.3.1
Choosing a Coaxial Cable
An appropriate coaxial cable matches the impedances of the antenna and receiver (50 ohms) and has a
line loss not exceeding 10.0 dB
.
If the limit is exceeded, excessive signal degradation may occur and the
receiver may not meet performance specifications. NovAtel offers several coaxial cables to meet GNSS
antenna interconnection requirements, including:
•
5, 15 and 30 m antenna cable with TNC connectors on both ends (NovAtel part numbers GPS-
C006, GPS-C016 and GPS-C032)
•
85 cm interconnect adapter cable used between the MCX and the TNC
connectors
- OEM615 NovAtel part number 01017278
•
22 cm interconnect adapter cable used between the MMCX and the TNC
connectors
- OEM617D, OEM628 and OEM638 NovAtel part number 01016772
2.3.2
Mounting the GNSS Antenna
After the OEM6 family card is installed in an enclosure, the antenna can be mounted and connected. The
GNSS receiver is designed to operate with any of the NovAtel single, dual and triple-frequency GNSS
antenna models. See
Section 2.3 Selecting a GNSS Antenna on page 22
for more information.
When installing the antenna:
•
Choose an antenna location with a clear view of the sky so each satellite above the horizon can
be tracked without obstruction. For more information on RF signal propagation and multipath,
refer to the NovAtel application note
APN-008 Discussions on RF Signal Propagation and
.
•
Mount the antenna on a secure, stable structure capable of safe operation in the specific
environment.
To select a coaxial cable for the application, consult the NovAtel application note
RF Equipment Selection and Installation
available at
. Also refer
to this application note if the application requires the use of cable longer than 30 m.
A conversion is required between the OEM638 and OEM628’s MMCX connector or the
OEM615’s MCX connector and the female TNC connector on NovAtel’s GNSS antennas.
NovAtel recommends using high quality coaxial cables because an impedance mismatch is
possible when using lower quality cables and this produces reflections in the cable that
increases signal loss. Although other high quality antenna cables can be used, the
performance specifications of the OEM6 family receivers are warranted only when used
with NovAtel supplied accessories.