Spectra Precision SP90m, Руководство пользователя

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antennas after measuring the elevation deviation and the
baseline length. The sign of the elevation offset is also
provided on the diagram below (elevation offset negative if
the secondary antenna is lower than the primary antenna and
vice versa).
The elevation offset should not be more than 45 degrees (or
less than -45 degrees)
, or the receiver will consider the
antenna setup to be invalid. No heading, roll or pitch
measurements would be calculated in this case.
Azimuth Offset
Ideally, the two antennas should be installed in such a way
that the baseline direction is strictly parallel or perpendicular
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 respect to the vehicle centerline.
When the baseline is strictly parallel to the centerline and it
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 respect to the vehicle
centerline may be intentional (see explanations in the next
section below).
Baseline length
Baseline Length (m)
Elevation Deviation (m)
Elev
ation
D
e
viation
Secondary Antenna
Primary Antenna
Elevation Offset (°)
Elevation Offset (°)
=
arcsin
[+]
[-]
V
ehicle
C
e
nt
erline
Azimuth Offset (°)
Secondary Antenna
Primary Antenna
Base
line
Di
re
ct
io
n
F
o
rw
ar
d mo
v
e
men
t