Circularly polarised microwave antenna.

p0001The invention relates to a microwave antenna for left-and right-circularly polarized electromagnetic waves, consisting of a waveguide radiator and two via a 90 - 3dB - coupler (hybrid) driven to 9₀° to one another arranged perpendicularly to the axis of the waveguide radiator excitation radiators.

p0002Such, for example, could also be used for the satellite known from practice microwave antenna is shown in FIG. 1 If you can be the radio frequency energy generated or received at one of the two mutually decoupled AnschluBtore the hybrid left-or right-polarized waves by feeding (transmission case) or removing (reception case). The respective other AnschluBtor is either finished, or used for receiving and transmitting the respective orthogonal components. The quality of the circular polarization depends in this known microwave antenna decisively on that the two connecting lines L₁, L₂ between the trained than connectors ST in the waveguide radiator HS dipping metal pins excitation lamps S and the hybrid H, and the metal pins and the connector precisely the same length. For example, the difference in length in the range of 12 GHz (satellite TV) may be only about o, l mm when a deviation from the required 90 ° phase difference of max. 3⁰ should be respected. However, these high demands on the manufacturing accuracy of the cables and connectors can be met in practice more complicated and more expensive only by means of production and assembly techniques.

p0003The invention is based is to provide a microwave antenna of the aforementioned type, which is simple and inexpensive, suitable as possible for mass production assembly with high precision of the phase difference between the polarization components the task. This object is achieved by the excitation DAB radiator, hybrid, and their interconnections are made in printing technology on a substrate of which the excitation radiator supporting part is arranged transversely in the waveguide radiators. The printed circuit is made with a single template photographically. In this erfindungsgemäBen microwave antenna, the advantage is achieved in a simple and elegant way, DAB necessary in the known antenna connectors and their inaccuracies omitted and beyond the connecting lines between the excitation emitters and the corresponding connectors of the hybrid by a correspondingly Big template virtually as accurate and also are extremely cost-effectively. Furthermore, the board is well suited for mass production, without any deterioration or DAB variations in accuracy are feared müBten. Rather, with the antenna erfindungsgemäBen the deviations from the 90 ° - keeping phase difference readily under 1 °. In addition, it has in comparison to the prior art described above also has a lower attenuation. Finally deleted by the erfindungsgemäBen build a might appear necessary weather protection (eg by covering the radiator - apertur) because the transversely in the waveguide radiators arranged substrate causes already holds a sufficient seal against weathering.

p0004The described in claim 2 embodiment of it - findungsgemäBen microwave antenna, a simple means is given to the hand, the shaft type conversion of the unsymme - tric coupling or decoupling the axisymmetric hollow _{Head wave} (When R_undh_Ohlleiter H₁₁- Type), thereby improving the adjustment, it being understood that the length of the metal strip is dimensioned according to the operating frequency range.

p0005The quarter-wave stub line formed by the structure governed according to claim 3, which is designed to be adjustable by means of an adjustable short circuit, if necessary, compensates for the generated by the excitation lamps interfering reactive components and also improved in the matching of the antenna. AuBerdem is generated in this way at a distance of a quarter wavelength of a longitudinal KurzschluB electroless plane in which the mounting of the substrate may not cause interference.

p0006Figures 2 and 3 show an embodiment of the erfindungsgemäBen microwave antenna, in which FIG. 2 is a 3 Axially-section and Fig. Is a plan view of the transversely inserted into the antenna substrate.

p0007The microwave antenna has a radiation direction in flared open circular waveguide - to spotlight Part 3 - Part 1 radiator and a shorted end 2 circular waveguide. Between the two means of attachment flanges 4, 4 'and 5, 5' and screws 6 firmly interconnected radiator parts 1, 3 is a substrate 7 is introduced, consisting of a double-coated with metal backing plate 8 of insulating material, said the radiant section 1 facing , together with the housing forming the ground plane Me - metal layer 9 having a circular recess whose diameter corresponds to the inner diameter of the circular waveguide, sodaB the electromagnetic waves can pass freely through the support plate eighth On the other side of the metal layer 10 to two AntennenanschluBleitungen 11, a connected thereto, made up of four each λ / 4 long, interconnected in a rectangular configuration interconnects hybrid 12, two exactly equal length lines 13 for connecting the hybrid 12 with two under 9₀° to each other excitation emitters 14, whose equal lengths from protruding into the radiant section 1 Endab - cut the lines 13 formed, as well as two of the He - lively spotlights 14 diametrically opposed, also projects into operating position in the radiator part 1 short, remaining with the ground plane lo associated metal strip 15 is etched away. The lines 11 and 13 are than 5₀-Ohm Lines formed in microstrip technology. In the assembled state of the microwave antenna, a channel 16 for non-contact arrangement of the connecting lines 13, the hybrid 12, and the AnschluBleitungen 11 is formed between the flanges 4 and 5, the latter, via a plug connection 17, of which one part is arranged in a holder 18 at secondary cable 19 are connected.

p0008By driving the two crossed excitation radiator 14 via a hybrid 12 which run in the lines 11 linearly polarized wave is in.eine from the hopper radiator - converted jettable or circularly polarized wave can be received. The entire microwave antenna through the complete structure in printing technology to äuBerst simple and cost - very accurately produced favorable manner in the dimensions. ort reaches the substrate 7 - In addition, by precise dimensioning of the antenna parts described on the one hand, and by the two in accordance with the respective operating frequency sized metal strip 15 and the short-circuited quarter-wave radiator portion 3 a very good adjustment and trouble-free extraction on insertion is.