Abstract. The task of narrow straight slot backscattering intensity
estimation has been solved. Here the slot is a groove or a through-thickness
gap in locally flat surface of metal object. The slot's cross-section is
supposed to be rectangular, while the width and the length of the slot are,
correspondingly, much less and much more than wavelength. Most intensive
scattering in the plane, perpendicular to the slot, has been estimated. The
reasons for two-position and one-position scattering intensity constancy, while
the direction of incidence is varying, have been found out. Simple formulae to
estimate groove's and through-thickness gap's radar cross section have been obtained,
using the one-mode approach and the equivalent surface currents technique for
entering and exit (the latest in case of through-thickness gap) surfaces of the
slot. The approach to numerically evaluate the admittance of external region,
adjoining to the entry (and exit) surface of the slot, has been suggested.
It
has been shown that once found admittance of external region for a particular width
of the slot can be used to evaluate scattering from the slot of the same width,
but of any type (groove, through-thickness gap) and depth. One-mode approach
with the accounting for the external region admittance results in high accuracy
calculation of slot's backscattering, particularly in the vicinity of
resonances in the groove, where its backscattering is the highest.
Key words:
backscattering, long narrow slot, groove, through-thickness gap,
formulae for radar cross section evaluation, one-mode approximation, external
region admittance.
References
1.
Kobak V.O. Radiolokatsionnie otradjateli [Radar Reflectors].
Ìoscow, Sov. Radio Publ. 1975.
248 p. (In Russian)
2.
Knott
E.F., Shaeffer J.F., Tuley M.T.. Radar Cross
Section - 2nd ed., SciTech Publishing, Inc., USA. 2004
3.
Lebedev
A.M., Furmanova T.A. Suppression Of Diffraction Noise Of Metal Plate Through Attenuation
Of Waves Traveling Along The Plate's Edges. Sbornik Trudov 4 Vserossiiskoi Mikrovolnovoi
Konferentsii [Proc. of 4-th All-Russian Microwave Conference]. Moscow, Kotelnikov IRE RAS, 2016, pp. 442-447
4.
Sazonov
D.M. Antenni and ustroistva SVCh [Antennas and Radar Frequency
Devices]. Moscow, Vishaya Shkola Publ. 1988. 434 p.
(In Russian)
5.
Peterson
A.F., Scott L.R., Mittra R.. Computational Methods For Electromagnetics.
IEEE, Inc., USA. 1998
For citation:
A. M. Lebedev,
T. A. Furmanova, A. I. Fedorenko, I .I. Krasnolobov.
Formulae
for narrow groove's and through-thickness gap's radar
cross section estimation.
Zhurnal Radioelektroniki - Journal of
Radio Electronics. 2018.
No. 5. Available at http://jre.cplire.ru/jre/may18/8/text.pdf
DOI 10.30898/1684-1719.2018.5.8