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Extra focusing multi-beam antenna for compensation of distortions of its reflector in operating conditions

Keywords:

A.G. Romanov – Ph. D. (Eng.), Main Designer of Development Activity, JSC Academician M.F. Reshetnev «ISS» (Zheleznogorsk)
E-mail: romanov@iss-reshetnev.ru
I.Yu. Danilov – Ph. D. (Eng.), Head of Department, JSC Academician M.F. Reshetnev «ISS» (Zheleznogorsk)
E-mail: danilov@iss-reshetnev.ru
V.V. Mochalov – Engineer, JSC Academician M.F. Reshetnev «ISS» (Zheleznogorsk)
E-mail: mvv115@mail.ru
Yu.I. Choni – Ph. D. (Eng.), Associate Professor, Kazan National Research Technical University named after A.N. Tupolev
E-mail: tchoni@rambler.ru


Even relatively small deviations of the large satellite hybrid reflector multi-beam antenna (MBA) shape caused by its non-uniform heating being under operational conditions lead to significant modification of large hybrid-reflector MBA characteristics. Primarily, this concerns the beam alignment. If a beamforming is performed through array feeds then the only way to stabilize their position data is associated with mechanical means ensuring reflector stiffness or beam recovery through compensating actions.
For beamforming, modern large hybrid-reflector MBAs use feed clusters. Under these conditions, it becomes possible to stabilize the beam alignment and beam parameters through adaptation of the cluster weight vector (power distribution of the cluster). For these purposes, pilot signals are used occasionally radiating by ground beacons. At the antenna array receiving elements’ outputs, complex amplitudes of these signals carry the antenna current state data and serve to regulate the weight vector in accordance with some adaptation algorithm. Ensuring a compliance of the weight coefficients with the complex-conjugate values of the pilot signal is widely used due to its simplicity and efficiency.
The paper contains the investigation of extra focusing effectiveness by the example of a large hybrid reflector offset MBA with the following parameters: reflector diameter Ø = 12 m, focal length F = 7.4 m, clearance H = 3 m, array area 2 m×1 m filled with feeds, which form 7-element hexagonal clusters with the hexagon side of 100 mm. The array center is located in the paraboloid focus, and its plane is inclined towards the reflector optical axis at the angle of 72°. It was assumed that reflector distortions lead to uncontrolled equivalent focus transition within a sphere with the radius of 72 mm.
Using the effective large reflector antenna simulating program, the multi-path computations were performed to evaluate the efficiency of the large hybrid reflector MPA extra focusing. The efficiency criteria were the minimum and average gain of the beam in its nominal direction under the ultimate deviations of the reflector equivalent focus. The calculations show that, without extra focusing, the gain decreases by an average of 1.5 dB with the maximum reduction of 2.7 dB. With the fixed number of clusters’ elements, the weight coefficients’ regulation reduces the losses to 0.3 and 0.6 dB, respectively. The adaptation of the cluster position along with the weight coefficients leads to even more significant results: 0.1 and 0.2 dB, respectively.

References:
  1. Rahmat-Samii Y. A generalized reflector/array surface compensation algorithm for gain and sidelobe control // IEEE AP-S Symposium. Blacksburg. VA. USA. 1988. AP. V. 19. № 4. P. 760−763.
  2. Gryanik M.V., Loman V.I. Razverty’vaemy’e zerkal’ny’e antenny’ zontichnogo tipa. M.: Radio i svyaz’. 1987. 72 s.
  3. Adelman H.M., Padula S.L. Integrated thermal structural electromagnetic design optimization of large space antenna reflectors // NASA-TM-87713. NASA Langley Research Center. Hampton. VA. USA. June 1986. URL = https://ntrs.nasa.gov/archive/nasa/ casi.ntrs.nasa.gov/19860019512.pdf (data obrashheniya 16.09.17).
  4. Shipilov S.E’., Efremov A.A., Yakubov V.P. Vosstanovlenie formy’ iskrivlenij zerkal’ny’x kombinirovanny’x antenn // Izvestiya VUZov. Fizika. 2008. T. 51. № 9/2. S. 103−105.
  5. Shendalev D.O. Proektirovanie formoobrazuyushhej struktury’ zontichnogo reflektora // Vestnik SibGAU. 2013. № 6(52). S. 164−173.
  6. Goldobin N.N. Metodika oczenki formy’ radiootrazhayushhej poverxnosti krupnogabaritnogo transformiruemogo reflektora kosmicheskogo apparata // Vestnik SibGAU. 2013. № 1(47). S. 106−111.
  7. Shenheng X., Rahmat-Samii Y., William A. Non iterative subreflector shaping for reflector antenna distortion compensation // IEEE Transactions on Antennas and Propagation. 2009. V. 57. № 2. P. 364−372.
  8. Gonzalez-Valdes B. Martínes-Lorenzo J.A., Rappaport C., Pino A.G. A new physical optics based approach to subreflector shaping for reflector antenna distortion compensation // IEEE Transactions on Antennas and Propagation. 2013. V. 61. № 1. P. 467−472.
  9. Acosta R.J. Compensation of Reflector Surface Distortions Using Conjugate Field Matching // International IEEE A/P-S Symposium and National Radio Science Meeting. Philadelphia. Pennsylvania. June 1986. P. 1−6. URL = https://ntrs.nasa.gov/archive/nasa/ casi.ntrs.nasa.gov/19860006991.pdf (data obrashheniya 12.09.17).
  10. Roberto J., Zaman A. Adaptive feed array compensation system for reflector antenna surface distortion // NASA-TM-101458. Prepared for the 1989 IEEE AP-S International Symposium and URSI Radio Science Meeting. San Jose. California. June 26−30. 1989.
  11. Alan R., Roberto J., Peter T., Lee Shung-Wu Compensation of reflector antenna surface distortion using an array feed // IEEE Transactions on Antennas and Propagation. 1989. V. 37. № 8. 1989.
  12. Smith W.T., Stutzman W.L. A pattern synthesis technique for array feeds to improve radiation performance of large distorted reflector antennas // IEEE Transactions on Antennas and Propagation. 1992. V. 40. № 1. P. 57−62.
  13. Pat. RU 2578289. H01Q 25/00. Sposob formirovaniya klasterny’x zon obluchayushhej reshetkoj mnogoluchevoj gibridnoj zerkal’noj antenny’ / Laskin B.N., Somov A.M.; zayavl. 29.12.2014; opubl. 28.03.2016.
  14. Ponomarev L.I., Vechtomov V.A., Miloserdov A.S. Bortovy’e czifrovy’e mnogoluchevy’e antenny’e reshetki dlya sistem sputnikovoj svyazi / Pod red. L.I. Ponomareva. M.: Izd-vo MGTU im. N.E’. Baumana. 2016. 197 s.
  15. Choni Yu.I., Shumina A.A. Vozbuzhdenie klastera obluchatelej gibridnoj zerkal’noj antenny’ v usloviyax deformaczii reflektora // Vseros. nauchno-prakticheskaya konf. AKTO-2016. T. 2. S. 753−759.
  16. Dy’mskij V.N., Choni Yu.I. Ob odnom reshenii zadachi sinteza antenn, dopuskayushhem e’ksperimental’noe modelirovanie // Izvestiya VUZov. Radiofizika. 1970. T. 13. № 9. S. 1389−1397.
  17. Choni Yu.I. Hodograph of antenna’s local phase center: computation and analysis // IEEE Transactions on Antennas and Propagation. 2015. V. 63. № 6. P. 2819−2823.
  18. US Patent 4 586 051. H01Q 19/10. Reflector distortion compensation system for multiple-beam wave satellite antennas / Saitto A., Mica G.; 26.04.1986.
  19. Huber S., Younis M., Krieger G., Moreira A., Wiesbeck W. A reflector antenna concept robust against feed failures for satellite communications // IEEE Transactions on Antennas and Propagation. 2015. V. 63. № 4. P. 1218 − 1224.

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