Citation: Speirs, P.J.; Ummenhofer,
M.; Schüpbach, C.; Renker, M.;
Wellig, P.; Cristallini, D.; O’Hagan,
D.W.; Kohler, M.; Murk, A.
Comparison of DVB-T Passive Radar
Simulated and Measured Bistatic
RCS Values for a Pilatus PC-12
Aircraft. Sensors 2022, 22, 2766.
https://doi.org/10.3390/s22072766
Academic Editor: Andrzej Stateczny
Received: 4 February 2022
Accepted: 30 March 2022
Published: 3 April 2022
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Article
Comparison of DVB-T Passive Radar Simulated and Measured
Bistatic RCS Values for a Pilatus PC-12 Aircraft
Peter J. Speirs
1,
* , Martin Ummenhofer
2
, Christof Schüpbach
3
, Matthias Renker
3
, Peter Wellig
3
,
Diego Cristallini
2
, Daniel W. O’Hagan
2
, Michael Kohler
2
and Axel Murk
1
1
Institute of Applied Physics, University of Bern, 3012 Bern, Switzerland; axel.murk@unibe.ch
2
Fraunhofer FHR, Fraunhofer Institute for High Frequency Physics and Radar Techniques, Fraunhoferstr. 20,
53343 Wachtberg, Germany; martin.ummenhofer@fhr.fraunhofer.de (M.U.);
diego.cristallini@fhr.fraunhofer.de (D.C.); daniel.ohagan@fhr.fraunhofer.de (D.W.O.);
michael.kohler@hensoldt.net (M.K.)
3
armasuisse W+T, 3603 Thun, Switzerland; christof.schuepbach@ar.admin.ch (C.S.);
matthias.renker@ar.admin.ch (M.R.); peter.wellig@ar.admin.ch (P.W.)
* Correspondence: peter.speirs@unibe.ch
Abstract:
Passive radar is a technology that has huge potential for airspace monitoring, taking
advantage of existing transmissions. However, to predict whether particular targets can be measured
in a particular scenario, it is necessary to be able to model the received signal. In this paper, we present
the results of a campaign in which a Pilatus PC-12 single-engine aircraft was measured with a passive
radar system relying on DVB-T transmission from a single transmitter. We then present our work
to simulate the bistatic RCS of the aircraft along its flight track, using both the method of moments
and the shooting and bouncing ray solvers, assess the uncertainty in the simulations, and compare
against the measurements. We find that our simulated RCS values are useful in predicting whether or
not detection occurs. However, we see poor agreement between simulated and measured RCS values
where measurements are available, which we attribute primarily to the difficulties in extracting RCS
measurements from the data and to unmodeled transmission and received path effects.
Keywords:
passive radar; bistatic RCS; RCS simulation; DVB-T; ultrahigh frequency; turboprop
aircraft; field measurements; signal processing; CFAR; range-Doppler analysis
1. Introduction
The research and development in the field of passive radar has been significant over the
last two decades. Passive radars have now become an established technology, approaching
the stages of commercialization [
1
,
2
] and certification [
3
]. As a consequence, the radar
community is now investigating advanced applications that can benefit from the particular
characteristics of a passive radar system. Among these, the antistealth capability of passive
bistatic radar is one of the most appealing. This relies on both the bistatic acquisition
geometry and on the low operating frequencies with respect to conventional monostatic
active radars. Although such a characteristic is known and reasonable, few works have
addressed the problem of experimentally verifying it [
4
–
6
]. Specifically, these works mostly
consider prediction detection capability of a given passive radar system and compare it
with experimental detection performance.
Passive radar antistealth capabilities can also be analyzed in terms of bistatic radar
cross section (RCS) [
7
]. That is, we analyze the bistatic RCS signature measured in time
for a given target over a specific target trajectory and target attitude. This approach has
been proposed as an aid to target tracking as well as a way to address automatic target
recognition (ATR) [8–12].
The problem of comparison between simulated and measured RCS for the active
monostatic case was addressed in [
13
,
14
]; in [
15
] a comparison between the simulated and
Sensors 2022, 22, 2766. https://doi.org/10.3390/s22072766 https://www.mdpi.com/journal/sensors
