New-Tech Europe | March 2017 | Digital Edition

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targets at user definable ranges
and radial velocities. The signal
generator also has multiple RF
sources, making it possible to test
radar against interference, as for
example co-existence with Long
Term Evolution (LTE) or other
radio-based services [2]. One can
also generate arbitrary waveform
files and transmit these additional
disturbing signals towards the radar
in order to test adaptive algorithms
like “constant false alarm rate”
(CFAR) or other land / sea clutter
mitigation techniques.
In addition to testing the functional
performance of the radar, the
COTS target generator can help
assess modern electronic protection
measures in the radar, helping
to prevent incidents such as the
disappearance of aircraft from
air traffic control radar caused by
military electronic warfare exercises
[3]. To test the performance of
the radar signal processing a radar
waveform is transmitted, delayed
and disturbed in the radar target
simulator. The radar receiver can
tell whether or not the echo return
was virtual or real using correlation
filters. An uncorrelated signal might
result from an ECM system due to
resampling at a different rate, a
small number of effective bits in
the ADC, phase noise or amplifier
distortions in the target simulator.
When using a DRFM, the generated
echo signal fidelity will likely be
different than one from a real
target. The radar processes focused
on electronic protection can detect
the differences from the returned
echo with different fidelity. This
measurement can also be assessed
by the presented radar target
generator.
Such demonstrations show clearly
that COTS test and measurement
systems address the test and
measurement of radars. In addition,
COTS test and measurement
equipment is able to generate also
radar echo signals with variable
range, radial velocity and radar cross
section. This combination makes
state of the art test equipment very
valuable and efficient instruments
for radar test.
References
[1] Small Business Innovation
Research (SBIR), Navy, Topic
N131-006, Acquisition Program,
"Direct Digital Radio Frequency (RF)
Conversion Digital Radio Frequency
Memory (DRFM)", 2013
[2] Heuel, S.; Roessler, A., "Co-
existence Tests for S-Band Radar
and LTE Networks", Microwave
Journal - Military Microwaves,
August 2014.
[3] Reuters, "Jets vanishing
from Europe radar linked to war
games", retrieved from http://www.
u s - e u r o p e - a i r p l a n e s - s a f e t y -
i d U S K B N 0 E O 1 CW2 0 1 4 0 6 1 3 ,
November 2014
Fig. 4: Single target generated by the COTS radar target
generator
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