11
７．Acquisition of RCS
Acquiring the target
’
s RCS value is done in the following two steps.
(1) Reference measurement of target with known RCS value
(2) Measurement of RCS value unknown targets and RCS calculation
The operation of each step is explained below.
(1) Measure reference with known RCS value
Measure the reflected reception power of the object to be measured (known target, CR corner reflector, etc.) whose
RCS value is already known and store it in the measuring device as a reference with correspondence between RCS
value and received power. In order to calculate the RCS value by measuring the measurement object whose RCS
value is unknown, it is necessary to memorize this reference in advance.
①
Measure the distance between the radar and the known target , set the distance range slightly longer so that the
reflected signal of the target
comes in
the distance range
in consideration of
the transmission pulse width (75
cm) of the radar.
And then acquire 2D imaging data.
(Note) Even if it is a point target like a CR,
its
Tx pulse width is 5 ns, and there is a received signal with a width
of
more than 75cm
in the distance direction. Please click the Recalculate button when changing distance
range.
②Drag the mouse in the image display area and place the target within the rectangular area.
By designating the range like this, it is possible to measure only the reflected signal of the desired target (CR).
(Reference) To check the actual θ, φ angle of the specified rectangular range, you can check the angles of the start
and end points by opening the setting and clicking Specify Rectangle Range as shown below. (It is also possible to
specify by specifying an angle at the start point and the end point of this rectangular range specification.)
③Enter the measured distance (m) of CR in the "measured distance" field of the " RCS Reference" frame, enter the
known RCS value (dBsm) in the "RCS value input" field. When clicking the Get Reference button, the values of
the "total received power value (Total Power)" field, the "peak power value (Peak Power)" field and the "RCS value
Release the left button here.
Hold the left button and
move the mouse
.
