GPS-704-X
The GPS-704-X is a wide band passive
antenna designed to operate at the
following frequencies (in MHz):
GPS L1 (1575.42), L2 (1227.60) and
L5 (1176.45)
Galileo L1 (1575.42), E5a and E5b (1164-1215) and
E6 (1215-1300)
Glonass L1 (1598 - 1611.5) and L2 (1242.5 - 1254.3)
OmniSTAR/CDGPS differential correction services (1525 - 1559)
This guide provides the basic information you need to install and
begin using your new antenna.
ADDITIONAL EQUIPMENT REQUIRED
The equipment listed below is required to set up the GPS-704-X:
•
A mount, such as a range pole, tribrach, or tripod, with a
5/8" x 11 thread that extends between 3/8" and 7/8" (9
mm and 22 mm)
•
A 1" open-end wrench
•
1 short coaxial cable with a male TNC connector for the
antenna
•
An external Low Noise Amplifier (LNA)
•
1 coaxial cable between the receiver and the LNA
•
Power supply and power cable (dependant on LNA)
SITE SELECTION GUIDELINES
Before installing the antenna, select a site that as closely as
possible meets the following conditions for optimal performance:
•
An unobstructed line-of-sight from horizon to horizon
and at all bearings and elevation angles
•
As far as possible from reflective objects, especially
those that are above the antenna and any water bodies,
which can be a strong source of multipath reflections
•
If obstructions and reflective surfaces are within 30 m,
ensure the site is as high as possible. Otherwise, mount
the antenna as low as possible.
INSTALLING THE ANTENNA
After a site has been selected, install the antenna as follows.
1.
Verify that the thread on the mount does not extend more
than 7/8" (22 mm) to ensure the plastic inside the antenna
receptacle is not damaged when the mount is inserted. If it
extends further than 7/8" (22 mm), add two jam nuts to
shorten the exposed thread, ensuring the nuts are well-tight-
ened.
2.
Align the mount thread with the metal adapter on the bottom
of the antenna and rotate the antenna clockwise until it is
securely screwed to the mount. Using a wrench, tighten the
adapter to the mount.
The metal adapter on the bottom of the antenna is fixed in place.
Do not attempt to remove it.
3.
Remove the dust cap from the antenna’s TNC connector.
4.
Attach the male TNC connector of the coaxial cable to the
antenna’s TNC connector. Mount an LNA close to the RF
output of the antenna, see
LNA Setup
later in this guide.
5.
Attach the other end of the coaxial cable to an LNA (
1
below), see the
LNA Setup
section of this guide. All NovAtel
GPS receivers provide a 5 V power source for the LNA
through their antenna RF connectors (
2
).
6.
The LNA may either receive power from a NovAtel receiver
or a separate power source. If you provide separate power
(
3
) to the LNA, you must insert a DC block between the LNA
and the receiver.
ANTENNA CARE
The GPS-704-X is designed to withstand the elements, including
rain, snow, and dust. However, to ensure your antenna performs
optimally, keep the radome (the top surface of the antenna)
clean and brush off any ice and snow. In addition, ensure the
TNC connector remains clean and dry and replace the dust cap
when a cable is not connected.
ELEVATION GAIN PATTERNS
SPECIFICATIONS
USER GUIDE
5/8 x 11
thread
"
3/8 - 7/8
9 - 22 mm
"
" (
)
Mount
Metal
adapter
Jam nuts
or flange
TNC connector
Coaxial
cable
LNA
User-
supplied
power
NovAtel
receiver
1
2
3
RF
3 dB pass band (typical)
1150-1650 MHz
Gain at zenith (
θ
= 90°) (min)
L1: +6 L2:+2.5 L5: +2 (dBic)
Gain roll-off (zenith to horizon)
L1: 14 L2: 11 L5: 11 (dB)
Polarization
Right-hand circular
Nominal impedance
50
Ω
VSWR
≤
2.0 : 1
POWER
See the
LNA Setup
section of this guide.
PHYSICAL
Diameter
185 mm (7.28
"
)
Weight
468 g (16.5 oz)
ENVIRONMENTAL
Maximum altitude
9000 m (29527.5 ft)
Operating temperature
-40°C to +85°C (-40°F to +185°F)
Storage temperature
-55°C to +85°C (-67°F to +185°F)
Salt spray
MIL-STD-810F Method 509.4
Ingress protection
IPX6 and IPX7
