Chapter 2 MarinePak7 Installation
NovAtel offers a variety of GNSS antennas with band pass filtering and an LNA (refer to our web site:
for details of available antennas). The GNSS antenna chosen depends
on the particular application. Each model offers exceptional phase center stability and a significant
measure of immunity against multipath interference. Each antenna has an environmentally sealed
radome and all meet the European Union’s Restriction of Hazardous Substances (RoHS) and Waste
Electrical and Electronic Equipment (WEEE).
For optimum GNSS tracking and Oceanix L-band reception, a cascaded antenna gain of +25 dB to +35
dB is recommended.
A dual frequency capable GNSS antenna is required to use SPAN, RTK or ALIGN.
2.5 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:
l
5, 15, or 30 m antenna cables with TNC male connectors on both ends (NovAtel part numbers
C006, C016 and C032 respectively)
For more information about antenna cabling, including using cables longer than 30 m and in-line
amplifiers, refer to APN-077: RF Equipment Selection and Installation available from
(
hexagondownloads.blob.core.windows.net/public/Novatel/assets/Documents/Bulletins/APN-
077-RFEquipmentSelection/APN-077-RFEquipmentSelection.pdf
).
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 OEM7 receivers are warranted only when used with NovAtel supplied
accessories.
MarinePak7 User Manual 2
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