Abstract
The design of a common ellipsoidal mirror for the focalization of several radioastronomic bands, by means of a straightforward method, is presented. Three bands centered at 100, 80 and 45 GHz are chosen for the validation of the method. Quasi-optics theory is used to design an optical system that can focalize several bands with the minimum possible optic elements, and also to share the maximum of them. Lenses, mirrors, feeder dimensions and the distances among each component necessaries for the focalization in each band are calculated. The simultaneous design in several radioastronomic observation bands reduces the cost of manufacturing, the total number of optic elements and the density of optical elements on the receiver cabin.
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REFERENCES
P.F. Goldsmith, “Quasioptical Systems,” IEEE Press/Chapman & Hall Publishers Series on Microwave Technology and RF. New York 1997.
Rohlfs K., Wilson T. L., “Tools of Radio Astronomy”, Springer, Third Edition, Astronomy & Astrophysics Library, 1999.
G. A. Deschamps, “Ray tehcniques in electromagnetics” Proceeedings of the IEEE, Vol 60, No 9, Sep. 197, pp 1022–135.
Kraus J.D., Radio Astronomy, “2nd Edition, Cygnus Quasar Books, 1986.
Burke F. B., Graham-Smith F., “An Introduction to Radio Astronomy”, Cambridge University Press, 2000.
López Fernández J. A. et al., “Configuración óptica del radiotelescopio de 40 m del CAY”, Technical repport of OAN, 2001.
J. Tuovinen, “Accuracy of a gaussian beam” IEEE Transanctions on antennas and propagation, Vol 40,No 4, Apt. 1992, pp 391–398.
L. Empacher, W. Kasparek, “Analysis of a multiple-beam waveguide for free-space transmission of microwaves” IEEE Transanctions on antennas and propagation, Vol 49, No 3, March 2001.
P.F. Goldsmith, “Quasi-optical techniques” Proceeedings of the IEEE, Vol 80,No 11, Nov 1992,pp. 1729–1747.
R.J. Wylde, “Millimetre-wave gaussian beam-mode optics and corrugated feed horns” IEEE Proceedings, Vol 131, Pt H, No 4,Aug. 1984, pp 258–262.
J.A. Murphy, “Distorsions of a simple gaussian beam on reflection from off-axis ellipsoidal mirrors”, International Journal of Infrared and Millimetre Waves, vol 8, pp 1165–1187, 1987.
A. Azeez, A. Rashed, B. Saleh, “Decentered gaussian beam”, Applied Optics, Vol 34,No 30, Oct 1995.
James W. Lamb, “Quasioptical coupling of gaussian beam systems to large Cassegrain antennas”, International Journal of Infrared and Millimetre Waves, vol 7,No 10, 1986, pp. 1511–1536.
Murphy J. A., A. Egan, S. Withington, “Truncation in millimetre and submillimetre-wave optical system” IEEE Transanctions on antennas and propagation, Vol 41,No 10, Oct. 1993, pp 1408–1413.
Carter M., Lamb J. W. “Proposal for a New layout Receiver cabin of the 30-m Telescope at Pico Veleta” IRAM Internal Report, 1995
García E., et al, “Analysis of the defocused Gaussian beam telescope on Cassegrain feeds” Microwave and Optical Technology Letters, Vol. 32,Number 6, March 2002, pp 420–423
Maffei B., Ade P. A. R., Tucker C. E., Wakni E., Wylde R.J., Murphy J. A., Colgan R. M., “Shaped corrugated horns for cosmic microwave background anisotropy measurements”, International Journal of Infrared and Millimetre Waves, Vol. 21,No 12, 2000, pp. 2023–2033..
Padman R., Murphy J. A., Hills R. E. “Gaussian Mode analysis of Cassegrain antenna efficiency” IEEE Transactions on antennas and propagation, Vol. AP-35,No 10, Oct. 1987, pp 1093–1103.
García E., et al, “Convergence of beam mode expansion coefficients for corrugated and conical feed horns”, accepted in PIERS 2002, Cambridge, Massachusetts, USA, 1–5 July, 2002.
García E. et al, “Feasibility study for the focalisation of the new 40m radiotelescope of Centro Astronómico de Yebes”, accepted in 13th Symposium on Space Terahertz Technology, Cambridge, Massachusetts, USA, 16–28 March, 2002.
Lamb J. W., “Optics study for ALMA receivers”, ALMA Memo 359, March 2001.
Withington, S. Yassin G., “A horn-reflector antenna for high performance submillimetre wave applications”, Proc 7 th Int. Sym. Space Terahertz, Charlottesville, pp 389–398, 1996.
Murphy J. A., “Aperture efficiencies of large axisymmetric reflector antennas fed by conical horns”, IEEE Trans Antennas Propag, Vol. AP-36, pp 570–575, April 1988.
Van Dooren G. A.J., Vant Klosster C.G.M., “Analysis of a reflector antenna with quasi-optical front-end using Gaussian beams”, JINA 90, pp. 201–205, November 1990.
Chu, T.S. “An imaging beam waveguide feed”, IEEE Trans. Antennas Propag., Vol. AP-31, pp. 614–619, July 1983.
Boucher D., Buric J., Bocquet R., Chen W., “Quasi-optical mirrors made by a conventional milling machine”, Int. J. Infrared Millimeter Waves, Vol. 13, pp. 1395–1402, September 1992.
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García, E., López Fernández, J.A., De Haro, L. et al. Design of a Common Ellipsoidal Mirror for the Focalization of Several Radioastronomic Bands: New Method and Application to Three Bands. International Journal of Infrared and Millimeter Waves 23, 1193–1213 (2002). https://doi.org/10.1023/A:1019611725506
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DOI: https://doi.org/10.1023/A:1019611725506