V. B. Khaikin, M. K. Lebedev

The paper is received on May 25, 2016

Abstract. In the present paper we describe the methods and results of the modeling and performance optimization of the imaging millimeter wave Cassegrain radiotelescope for solar research. We propose to use the 2-row densely packed array feed as a receiver, aligned with one image coordinate, and active beam scanning along the other one in order to maximize the number of pixels and achieve the best image quality with a feed of minimal size and weight. To solve the problem, conventional methods of antenna engineering and radioastronomy, as well as milli­meter-wave imaging approaches were employed. Beam scanning optical sys­tems with tertiary and secondary optics were considered. Two kinds of systems using tertiary mirror were studied, with an elliptic tertiary, and with a hyperbolic one, for the case of a magnification Ě = 10. The auxiliary swinging flat mirror is used for the beam scanning in those systems. In the system with a secondary optics, the beam is scanned using the subreflector, the case of M = 3 is considered. An optical design using secondary optics is shown to be more appropriate for the beam scanning.

Key words: solar radioastronomy, multibeam radiotelescope, secondary and tertiary optics, ray tracing, multibeam pattern modeling.

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