Manual

RaDeKL Radar ICD
107-201-001 ISSUE 2.10
MULTISPECTRAL SOLUTIONS, INC. PROPRIETARY AND CONFIDENTIAL
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levels are chosen based upon their exceeding threshold 13 out of 16 times. By re-
sampling the radar field of view using different threshold settings, it is possible to
improve return signal amplitude resolution to improve the understanding of the reflective
radar environment.
Since the radar was developed to support radar signal processing, the antenna beam
pattern is shown in the following figures for different frequencies and elevation and
azimuth planar cuts. These figures represent the general antenna pattern characteristics.
The true pattern will vary slightly from the one shown in the figure. The actual antenna
pattern must be determined with a calibration range.
1.3 System Operation
One important phenomenon that is necessary to understand for the operation of the radar
is the effect of multi-path on surface-to-surface radar detection performance. When the
radar is mounted near the ground with targets near the ground, the reflection from the
earth in the transmit and receive paths provides some cancellation of the direct path
signal due to the fact that these ground bounce paths are slightly longer with a phase
reversal upon reflection. Figure 3 illustrates the potential signal paths between the radar
sensor head and the target.
Figure 3: Surface-to-Surface Radar Operation with Multipath
Since the reflections combine with the direct path signal, the radar return will observe
both constructive and destructive interference depending on the heights sensor head and
target and the range between the sensor head and target. Figure 4 shows the variation of
h
a
h
t
R
h
a
-h
t
h
a
+h
t
L
direct
= (h
a
-h
t
)
2
+ R
2
L
reflect
= (h
a
+h
t
)
2
+ R
2
θ (Incidence Angle)
1
3
2
4
Reflectivity of
the surface
h
a
h
t
R
h
a
-h
t
h
a
+h
t
L
direct
= (h
a
-h
t
)
2
+ R
2
L
reflect
= (h
a
+h
t
)
2
+ R
2
θ (Incidence Angle)
1
3
2
4
Reflectivity of
the surface