**Abstract.**
Semi-transparent screen forming a cut-off pattern is discussed. The results
are relevant to jamming protection, electromagnetic compatibility and satellite
positioning. In the geometrical optics (GO) limit,
analytical approximations for impedance distribution along the screen have been
developed; it has been shown that the
impedance is pure resistive. To determine the domain of applicability, a
numerical procedure has been implemented as a solution of the integral equation
by the method of moments. The GO approximation becomes inapplicable as the
distance between the source and the screen decreases.
Beyond the GO approximation, an optimization procedure for
synthesis of impedance distribution has been employed.
At each step of the optimization procedure, the solution of the direct problem
in the form of an integral equation was carried out for a certain profile of the
impedance. Minimization of the quadratic functional describing the desirable
cutoff of source radiation pattern has been employed. Resulting impedance occurs
to be complex with a positive (resistive) real part.
Numerical estimations are discussed including that of the frequency
dependence of impedance distribution. It has been shown that the main constraint
factor for achieving the desired cut-off pattern is the distance between the
source and the screen.
For the distances more than 10 wavelengths, a 40dB cutoff is achievable within
an angular sector of +/-10 degrees around a desirable light-shadow boundary.
With one wavelength distance, the cutoff is 20dB. The
related figure is potentially valid for 0.5 wavelength distance.

**Key words:**
Half-plane diffraction, semi-transparent sheet, cut-off pattern.

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For citation**:**

D.V.Tatarnikov, A.A.Generalov^{.
}Synthesis of
semi-transparent screen forming a cutoff pattern. *Zhurnal Radioelektroniki - Journal of Radio Electronics, *
2017, No. 2.* *Available at http://jre.cplire.ru/jre/feb17/7/text.pdf.
(In Russian)