volume | PIER Journals

2008-02-04

The Phase Centre of a Pure Mode, Smooth Wall, Conical Horn

Harry Green

Professor Harry Green

University of South Australia

Australia

Homepage

Progress In Electromagnetics Research B, Vol. 4, 285-298, 2008

doi:10.2528/PIERB08010705

Abstract

In this paper the phase centre of a pure mode, smooth wall, conical horn is studied. The method employed uses phase information obtained by aperture integration of the phase corrected mode field but differs from earlier presentations in first reducing the radiation integrals in terms of an identified family of functions prior to integration. The result is formulas for the principal plane radiation patterns that better exemplify operation of the antenna. The procedure uses these formulas together with least squares minimization to determine a best fit phase centre for each principal plane. It is shown that contrary to published results, even in its principal planes, there is no unique phase centre that is a property of the horn alone. The use of such a horn as the feed element of a radio-optical antenna system is then considered. It is shown that in situations where cost is paramount and the well known drawbacks of its unequal principal plane beamwidths and the diminished gain that results from lackof a uniquely defined phase centre can be tolerated, perhaps contrary to conventional wisdom, the pure mode, smooth wall, conical horn does have a useful role to play. This is illustrated by a design example in which such a horn was used to feed a 6.4 m. dish working in X-band with a Gregorian feed system. The result is confirmation of the usefulness of the method presented here for location of a best fit phase centre.

Citation

Copy Export

Harry Green, "The Phase Centre of a Pure Mode, Smooth Wall, Conical Horn," Progress In Electromagnetics Research B, Vol. 4, 285-298, 2008.
doi:10.2528/PIERB08010705

References

1. Green, H. E., "The radiation pattern of a conical horn," Journal of Electromagnetic Waves and Applications, Vol. 20, 1149-1160, 2006.
doi:10.1163/156939306777442999

2. Shafia, L. and A. A. Kishk, "Prime-focus waveguide feeds," Microwave Horns and Feeds, Olver, A. D., et al. (eds.), IEE Books, London, 1994.

3. Kildal, P. S., "Combined E- and H-plane phase centers of antenna feeds," IEEE Transactions on Antennas and Propagation, Vol. 31, 199-202, 1983.
doi:10.1109/TAP.1983.1143009

4. Rao, K. S. and L. Shafai, "Phase center calculations of reflector antenna feeds," IEEE Transactions on Antennas and Propagation, Vol. 32, 740-742, 1984.
doi:10.1109/TAP.1984.1143406

5. Rusch, W. V. T. and P. D. Potter, Analysis of Reflector Antennas, Academic Press, 1970.

6. Wylie, C. R. and L. C. Barrett, Advanced Engineering Mathematics, McGraw-Hill Book Coy, 1982.

7. Milligan, T. A., Modern Antenna Design, IEEE Wiley-Interscience, 2005.

8. Milligan, T. A., "Universal patterns ease circular horn design," Microwaves, Vol. 20, 83-86, 1981.

9. Muehldorf, E. I., "The phase center of horn antennas," IEEE Transactions on Antennas and Propagation, Vol. 18, 753-760, 1970.
doi:10.1109/TAP.1970.1139799

10. Hu, Y. Y., "A method of determining phase centers and its application to electromagnetic horns," Journal of the Franklin Institute, Vol. 27, 31-39, 1961.
doi:10.1016/S0016-0032(61)91013-4

11. Green, H. E. and W. G. Cowley, "Antenna refurbishment for use in a low-earth-orbit satellite earth station," Australian Journal of Electrical and Electronics Engineering, Vol. 3, 177-188, 2007.