Technical information

high-speed, single-pole, double-throw (SPDT) waveguide switch is installed in each channel
(SWlOl, SW102) to extract the low-beam signal for processing in the RDA. The added switch is
slaved to the existing RAG beam switch (S2, S3) so as to direct the low-beam signal to the RDA
receiver when the high-beam horn is connected to the target channel receiver. The low-beam
signal is connected to the target channel receiver under ASR-9 RAG control beyond the nominal
15 nmi range.
The insertion loss associated with these added waveguide switches increases the ASR-9
target channel’s low-beam receiver minimum detectable signal (MDS) by approximately 0.5 dB.
This will decrease the nominal detection range for a 1 square meter aircraft on the nose of the
beam by roughly 2 nmi. Since the ASR-9 system exceeds its detection envelope requirement by
more than this margin, the resulting decrease in performance is not expected to have an
operational impact on its aircraft surveillance function.
0m
* N” A
High Beam Waveguide
r-.----~--
, Cncular Polarization
High & Low Beam
I
-0
1 Highl3wn
I
-
I
channelr nSSw
Low BeamJaveg$de , 2 ,?-, ~
Channel1
+ Traffic
“B”
ASR-9 wsp
1 I
.
HF+SWg- Fl.3
C-SW
I
>A
I
S6 1
I-,-,---------J
Figure 10. Simplified Waveguide Assembly Line Drawing.
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