Die Erfindung betrifft eine Empfangseinrichtung fur links- und rechtsdrehend zirkular polarisierte Mikrowellensignale. The invention relates to a receiving device for left-handed and right-handed circularly polarized microwave signals. Dabei ist der zur Antenne gehorende Speisehohlleiter (H) als Bandpasfilter (BP) ausgebildet und an den Speisehohlleiter ein die Umsetzerschaltung tragendes Mikrostreifenleitersubstrat (MS) angekoppelt. In this case, the belonging to the antenna feed waveguide as a bandpass filter (BP) is (H) and is coupled to the waveguide feeder which a converter circuit carrying microstrip conductor substrate (MS). Weiterhin ist die Ankopplung (K1, K2, K3, K4) so gestaltet, das sie die Funktion eines Polarisationswandlers ubernimmt, oder es ist direkt in den Speisehohlleiter ein Polarisationswandler (T1, T2, A1, A1', A2, A2') integriert. Furthermore, the coupling (K1, K2, K3, K4) designed so that it assumes the function of a polarization converter, or it is directly in the feed waveguide, a polarization converter (T1, T2, A1, A1 ', A2, A2') are integrated. Auf diese Weise ist eine sehr einfache, kompakt aufgebaute Empfangseinrichtung realisiert (Fig. 3a). In this way is achieved a very simple, compact built-up receiving means (Fig. 3a).

Microwave receiving arrangement

In an antenna having a main and an auxiliary reflector, whose supply system ensures optimum illumination of the main reflector, interfering reflections are suppressed as far as possible. A dielectric moulded body (D), which is provided with a reflecting end surface which carries out the function of the subreflector (SR), is inserted into the exciter (E) of the antenna. The dielectric moulded body (D) has a layer with a smaller material thickness, so that the effective dielectric constant of this layer is reduced with respect to the dielectric constant of the rest of the moulded body (S).

Dual reflector antenna

The present invention relates to a conical scanning process in a radar antenna. The antenna comprises a principal parabolic reflector (1) and a primary rear-feed source (2) fed by a circular waveguide (3) and displaced with respect to the focus of the parabolic reflector (1). The conical scanning is produced by the rotary movement of the parabolic reflector (1) about the source (2), the said source (2) and the circular guide (3) remaining fixed. The present invention is applicable to tracking radars operating in the millimeter waveband.

Conical scan process in a radar antenna, radar antenna implementing such a process and use of such an antenna in a tracking radar

Antenne a balayage conique et utilisation d'une telle antenne dans un radar de poursuite

L'invention concerne une antenne (10) pour un satellite spatial comprenant au moins : un guide d'ondes (20) ayant d'une extremite (21) destinee a emettre ou a recevoir une onde electromagnetique, une structure piege a ondes de surface (30) solidaire de l'extremite du guide d'ondes, ladite structure comprenant une surface (31) s'etendant transversalement par rapport au guide d'ondes a partir de laquelle font saillie des anneaux concentriques (32) autour du guide d'ondes, caracterisee en ce qu'elle comprend en outre une lentille dielectrique (60) fixee sur l'extremite (21) du guide d'ondes, la lentille presentant une forme de revolution autour d'un axe (X) du guide d'ondes, le diametre de la lentille etant croissant en s'eloignant de l'extremite du guide d'ondes, et en ce que la lentille presente une permittivite dielectrique relative effective superieure a 1 et inferieure ou egale a 5.

Antenne pour un satellite spatial

A waveguide (1) which passes axially through the parabolic reflector (5) is terminated in an insert piece consisting of a sharp end (6), a cylindrical portion (2) and an expanding portion (3) made in one piece of a dielectric material having a dielectric constant of 2,5 to 3,5. The front end is intended so as to form a triangular cross section with an azimuth angle (alpha) of 150 deg. the surface of which is metallised and acts as a reflector. The sharp end (6) faces incoming radiation propagated in the waveguide (1) and reduces partial reflection at the transition to the dielectric material. The merit of this arrangement is that a ray element (1) which in a traditional construction would be lost in that it would bypass the auxiliary reflector, is through double reflection from the inside of the insert piece (3) and the metallic surface (4) included in the beam emitted by the reflector (5). Also, the construction is robust and does not require auxiliary mirror support struts which in older designs disturb the homogeneity of the emitted beam.

Gert Nottebom

Papers

Cassegrain excitation wave guide arrangement for parabolic antenna - uses glass fibre reinforced insert piece as secondary reflector carrier

Cassegrain-erreger-system fuer eine parabolantenne