ORBIT FR Horizontal Scanners User Manual
Horizontal scanners, Near -field scanners
18
NEAR
-FIELD SCANNERS
www.orbitfr.com
ORBIT/FR planar scanners are available for
horizontal mounting. Horizontal mounting of
scanners is useful when the AUT is designed to
be supported from below, or cannot be mounted
to face a vertical scanner. The most common
example of this type of antenna is a space borne
type. Other examples include large reflectors
and some vehicle mounted antennas.
The AL-4951 and AL-4952 family of scanners,
up to 9 x 9 feet (2.7 meters square), may be
ordered by substituting an H for the V in the part
number. The AL-4953 and AL-4954 series may
be ordered in 1 meter increments in each axis
starting at 4 meters in length. The part
numbering is the same as the horizontal versions
with an H substituted for the V in the part
number.
The large horizontal scanners are constructed
from lightweight steel trusses. The X-axis is
supported on a frame with multiple precision
linear rails. The X-axis rides on linear bearings
below the support frame. Multiple pinions on a
common shaft drive the X-axis by engaging
racks along side the rails.
The Y-axis carriage travels along the X-axis
using a similar arrangement of 2 parallel linear
rails and bearings; a rack and pinion drive is also
used. The carriage is able to carry a Z-Roll
assembly and the probes. The large capacity
allows the use of a distributed network analyzer
on the probe carriage.
Horizontal scanners may be mounted in several
ways. Contact ORBIT/FR with information about
the facility in which the system is to be installed
for a detailed design proposal. Horizontal
scanners may be mounted to existing steel
beams or concrete pillars within a building. New
steel or concrete footings can be installed. Most
installations require a combination of these
techniques.
For applications that require special
configurations, scanners are available that place
a linear slide on the floor and a single axis
suspended from overhead. This combines
motion of the AUT and the probe to produce a
planar scan.
A variety of software correction techniques can
be employed to improve performance. These
techniques are based on optical and laser
calibration of the scanner actual position
measured with the optical system and compared
to the encoder reported position. For most
applications, the purchase of an expensive laser
system is not required.
Horizontal Scanners
1. High-speed option: Y-axis only for all models, 350 mm/sec (14 in/sec).
2. AL-4953 series X and Y = 3 to 12 meters in 1 meter increments, AL 4954
series X and Y = 13 to 25 meters in 1 meter increments.
Notes
AL-4951-H Series
AL-4952-H Series
AL-4953-H Series
AL-4954-H Series
Horizontal Scanners