ashtech HDS800, Reference Manual

Page: 39 / 678

23
Receiver Description
Azimuth Offset
Ideally, the antennas should be installed to generate a
baseline strictly parallel or perperpendicular to the vehicle
centerline. However, you may also be facing some installation
constraints on your vehicle compelling you to install the
antennas differently. The azimuth offset describes the non-
alignment of the baseline with the vehicle centerline. When
the baseline is strictly parallel to the centerline and the
baseline is oriented in the direction of forward movement, the
azimuth offset is zero. In all other cases, the offset is non-
zero and should be measured as shown in the diagram below.
The non-alignment of the baseline with the vehicle centerline
may be intentional (see explanations in the next section
below).
Correlation Between
Azimuth Offset,
Antenna Setup &
Measurements Made
Consider the following four setups before installing your
antennas. A ship is shown in the examples but this could be
any other type of vehicle.
Depending on the type of measurements you wish the
receiver to perform (roll or pitch) and the
installation possibilities offered in the vehicle, you will
choose the most appropriate setup and set the azimuth offset
accordingly.
V
ehicle
C
ent
erline
Azimuth Offset (°)
Antenna #2
Antenna #1
Baseline
Dir
e
ction
F
or
w
ar
d mo
v
emen
t