**Abstract**.
Misphased horn feed for compact range MAK-5M is investigated. The slant of the
horn aperture in the vertical plane obtains the nonaxisymmetrical radiation
pattern. The form of the diagram help to achieve uniform field distribution on
the surface of the reflector. The radiation pattern has a region with
approximately constant value of the amplitude of the field in the horizontal
plane due to the fracture of lateral side of the horn. Angle of the slant and
flare angle of the big horn are optimized for making the best form of radiation
pattern.

Electrodynamic calculation was
carried out by the method of the integral equations (method of moments) using
FEKO. Using cluster of ITAE RAS allowed carrying out simulation of the field
distribution in the quite zone of the compact range in all frequency range. The
system of horn feed and reflector is considered in free space, the reflection
from the chamber walls are not taken into account.

Compact range MAK-5M with misphased
horn feed will be in the quit zone diameter of 2.5 m non-uniformity field not
exceeding ± 1 dB, and the phase of the non-uniformity of less than 10°. It is
mean the compact range with misphased horn feed allows you to expand the quite
zone of the about 25% in the frequency band from 9.8 to 12 GHz.

**Keywords**:
feed reflector, compact range, computer modeling by FEKO.

**References**

1.
Balabukha
N.P., Zubov A.S., Solosin V.S. *Kompaktnye poligony dlya izmerenii
kharakteristik rasseyaniya ob’ectov.* [Compact range for measurements of object scattering
characteristics]. Moscow, Nauka Publ. 2007. 266 p. (In Russian)

2.
Aizenberg G.Z., Yampol’skii V.G., Tereshin O.N. *Antenny
UKV.* [Antennas VHF]. Moscow, Svyaz’ Publ. 1977. P. 1, 383 p. (In Russian)

3.
Erukhimovich Y.A., Timofeeva A.A. *Kombinirovannye rupornye
obluchately dlya zerkal’nykh antenn.* [Combine horn feed for reflectors]. *Trudy
NIIR. *1979. ¹ 1. (In Russian)

4.
Mather J. C. Broad-Band Flared Horn with Low Sidelobes. *IEEE
Transactions on Antennas and Propagation. 1981.* V. AP-29, N. 6, November.

5.
Burnside W. D., Chuang C. W. An Aperture-Matched Horn Design.
*IEEE Transactions on Antennas and Propagation.* 1982. V. AP-30, N. 4,
July.

6.
Olver A.D., Xiang J. Design of profiled corrugated horns. *IEEE
Transactions on Antennas and Propagation.* 1988. V. 36, N. 7, July.

7.
James G.L., Clark P.R. Greene K.J. Diplexing feed assemblies
for application to dual-reflector antennas. *IEEE Transactions on Antennas
and Propagation*. 2003. V. 51, N. 5, May.

8.
Balabukha N.P., Grigor’eva M.I., Kurochkin A.P. and others.
Dielectric rod feed with radiation pattern of the special
form. *Antenny – Antennas.* 2001. N.2. p. (In Russian)

9.
Balabukha
N.P., Basharin A.A. A rod dielectric wide-band feed. *Antenny –
Antennas*. 2008. N.12. 65-72 p. (In Russian)

10. Glazman
Y.D., Korshunova N.V., Timofeeva A.A. *Uluchshenie osevoi simmetrii glavnogo
lepestka i snijenie urovnya bokovogo izlucheniya rupornykh antenn.*
[Improving the
axial symmetry of the main lobe and the sidelobe reduction in the level of horn
antennas]. *Trudy NIIR*. 1990. N3. (In Russian)

11.
Dronova V.A., Kozlovskay I.A. Timofeeva A.A., Khlopkova Z.K.
*Vybor** formy
raskryva neosesimmetrichnykh antenn v zavisimosti ot diagrammy napravlennosti
obluchatelya.* [Selection shape of an aperture nonaxisymmetric
antennas depending on the radiation pattern of the feed]. *Trudy NIIR.*
1987. N3. (In Russian)

12.
Timofeeva A.A. *Opredelenie geometricheskikh razmerov
rupornykh obluchatelei s diagrammami napravlennosti blizkimi k optimalnym.*
[Determination of the geometric dimensions of a feed horn antenna with
radiation patterns close to optimal.]. *Electrosvyaz’.* 1977. N5. (In
Russian)