DE4412770A1 - Microwave lens aerial for car distance warning radar - Google Patents

Abstract

The aerial has a radiation excitation system and a dielectric lens (5) transparent to electromagnetic waves. The radiation excitation system generates a left, middle and right radiation lobe (4, 2, 3) by three separately switchable exciters (8, 6, 2).The left- and right-hand lobes (4, 3) overlap the middle one (2) in the flank suction of the horizontal aerial diagram. The lens is of collector type with a short focal length comprises thick and loss reducing steps. Pref., the radiation lobes have stronger beams in the vertical plane.

Description

The invention relates to a microwave lens antenna nenanordnung for motor vehicle distance warning radar according to the Preamble of claim 1.

To increase the safety of motor vehicles on the road traffic and to relieve the driver are warning signals or automatic measures in the event of a too tight opening possible obstacle, especially the vehicle in front, he wishes. This includes information about the distance and the relative speed to the obstacle is necessary. This information One can, for example, send out a suitable Neten electromagnetic microwave signal from one to the Front of the motor vehicle mounted antenna and on closing reception of the signal reflected at the obstacle receive. The antenna is said to be sharply focused Generate a beam that only illuminates the obstacle. There the dimensions of the antenna should be small so that for example, integration into the bumper is possible, a high frequency must be chosen in order to achieve a sufficient frequency To achieve beam bundling. The depth of the antennas unit should also be very low. So that in curves the Antenna beam aimed at the vehicle in front remains and no misinformation, for example from Leit planks, be received, it is important that the beam lobe by a small angle to the right or to the left can be pivoted to the left. Because such a pivoting process should run quickly and reliably, has an electrical Switch over advantages over swiveling with mechanical means.  

An antenna for a motor vehicle range radar, however with only one non-swiveling club is over DE-OS 38 40 451 known. It is a Lens antenna, which is fed by a horn. With this known lens antenna can be a directional Statistics with widely differing club widths in two realize orthogonal cutting planes. The lens points to this different lens cone in two orthogonal sectional planes ture, with the contour in the first section plane like this is chosen that one originating from the focal point of the lens Ball shaft after passing through the lens in a wave flat phase fronts is transferred while the contour is in the cutting plane orthogonal to this is selected so that the spherical wave originating from the focal point after passing through the lens still has non-plane phase fronts.

The object of the invention is for a motor vehicle distance warning radar an inexpensive, especially a large series manufacturing micro with extremely low unit costs wave lens antenna assembly to create a fast and reliable pivoting of the main orthogonal in two planes of radiation beam of different widths le allowed to the left or right while doing so in one building shape with very small external dimensions, especially what the depth dimension is feasible.

This task is arranged in a microwave lens antenna tion according to the preamble of claim 1 by the im characterizing part of this claim specified features solved.

The lens antenna arrangement according to the invention thus has three horizontally arranged in the focal plane of the lens Pathogens, each with its own radiation lobe is arranged. The lobes have in the horizontal plane for example a half width of about 3 ° and in the Vertical plane about 5 °. The offset of the pathogens from the Mit  telachse determines the deflection of the radiation lobes. By electronic switching from the middle to the right or left exciter of the radiation excitation system can from a central lobe to one side deflected beam are switched. The pathogens are so close together that the radiation lobes overlap in the flank area. Realizing the required Lich small width and height of the aperture of, for example se 100 mm × 75 mm is due to a high operating frequency of for example, 77 GHz ensured. A shallow depth is achieved by a lens with a short focal length, which is used for Reduction of lens thickness and losses as well Stepped lens is executed. Step lenses are very narrow dig and can usually hardly be used here but good because of the very narrow transmission band be used.

Appropriate training and execution options of Invention are specified in the subclaims.

The invention and exemplary embodiments thereof are described in the fol explained with reference to eleven figures.

Show it:

Fig. 1 is a sectional view of an in a housing housed lens antenna device according to the invention, with associated radiation lobes

FIG. 2 is a similar view, but with an alternative lens design,

Fig. 3, 4 and 5 are schematic representations of consisting of three waveguide radiators each radiation exciter systems for a lens antenna arrangement according to the invention,

Fig. 6 is a schematic representation of a three patch antennas existing radiation exciter system for a lens antenna arrangement according to the invention,

Fig. 7 is an oblique view showing the outer structure of an embodiment of a car Abstandswarnradar- front end with an integrated lens antenna arrangement,

Fig. 8, the interior of the structure of the front end of FIG. 7,

Fig. 9 is a sectional view of a front-end embodiment with separate transmit and receive antenna,

A cross-sectional view of the radiation lobes Fig. 10 by the antenna arrangement of FIG. 9 produced,

Fig. 11, the apertures of the two in the embodiment of FIG. 9 used for antennas 45 ° -Linearpolaristion.

In Figs. 1 and 2, a front-end housing is shown in each case as well as 1 for a Kraftfahrrzeug-Ab level warning radar with lens antenna arrangement of this the generated beams 2, 3 and 4 in a sectional view from above. This front-end housing 1 is attached to the front of a motor vehicle. The cuboid, made of sheet metal housing 1 is open to the front and there weatherproof covered with a dielectric lens 5 , which is permeable to electromagnetic waves and z. B. consists of polystyrene. The radiation exciter system consists of three separately switchable, horizontally arranged in the focal plane of the lens 5 side by side exciters 6 , 7 and 8 men. In this case 2, the average excitation 6 generates the average radia tion lobe of the left exciter 7, the right-hand beam 3 and the right exciter 8, the left lobe. 4 In addition to the lens 5 and the exciters 6 , 7 and 8 , subordinate electronic switching elements are accommodated in the compact cuboid housing 1 . The housing 1 has connections on the back or on another side wall for supplying power to the electrical switching elements and for forwarding information from the housing 1 to an external computer in the motor vehicle. The housing walls on the side of the lens 5 are coated with a microwave-damping layer 9 to avoid wall reflections. The radiation lobes 2 , 3 and 4 have, for example, a half-width of about 3 ° in the horizontal plane and about 5 ° in the vertical plane. The offset of the exciters 7 and 8 from the central axis determines the deflection of the radiation lobes 3 and 4, respectively. By electronically switching from the middle exciter 6 to the right or left exciter 7 or 8, it is possible to switch from the central radiation lobe 2 to a radiation lobe 3 or 4 deflected to the side. The exciters 6 , 7 and 8 are so close together that the radiation lobes 2 and 3 or 2 and 4 overlap in the flank area. The implementation of the required small width and height of the antenna aperture of, for example, 100 mm × 75 mm is ensured by a high operating frequency of, for example, 77 GHz. A shallow depth is achieved by a lens 5 with a short focal length, which is also designed as a stepped lens to reduce the lens thickness and the losses. Step lenses are very narrow-band, but can also be used for this purpose because of the very narrow transmission band.

In order to counter the risk of contamination on the outside of the lens 5 facing away from the vehicle, the steps, as shown in FIG. 1, are preferably attached on the inside. In individual cases, however, it can be expedient, as shown in FIG. 2, to also attach them to the outside. In this case, with an additional low-loss radome window 10 with a smooth outer surface, better protection against contamination can be achieved. If the lens antenna arrangement has an in-phase aperture, the rays emerge parallel to the axis of rotation. The embodiment shown in FIG. 2 in this case has the advantage over the embodiment according to FIG. 1 that no graded shadow areas in the aperture result from the gradation of the lens 5 on the outside, which lead to an increase in the side lobe in the radiation diagram.

As shown in FIG. 1, both lens surfaces can be curved. However, as shown in FIG. 2, one of the lens surfaces, apart from the possible gradation, can also be flat. The radiation behavior can be optimized through a special choice of lens contours. For example, laterally offset exciters 6 , 7 and 8 resulting imaging errors can be reduced. To avoid reflections, one of the lens surfaces can have changes. Such changes can be, for example, suitably sized bores which are uniformly distributed over the surface or a surface layer of suitable thickness with a low dielectric constant.

In order to achieve a different bundling of the antenna in the horizontal and vertical plane, a rectangular or elliptical aperture of the lens 5 is suitable. The long side lies in the plane with the higher club bundle. In this case, the pathogen diagram should also have different bundling in both levels. This is achieved with rectangular excitation apertures, the edges of which are also vertical or horizontal. Square or circular excitation apertures are also possible because of the mostly different bundling in the E and H planes. The exciters in question here, namely waveguide radiators or patch antennas, are then either vertically or horizontally polarized depending on the feed.

In the exemplary embodiments according to FIGS. 1 and 2, horns or waveguide exciters are used as exciters 6 , 7 and 8 . In individual cases, it may be necessary to make the exciter apertures of horn radiators so large that a low lens overexposure would result in an overlap of adjacent exciters. In this case, smaller, non-overlapping apertures can be used if the directivity of the exciters 6 , 7 and 8 , as shown in FIGS. 1 and 2, is reinforced by dielectric rod radiators 11 inserted into the radiator openings.

To the trained as horn emitter or waveguide exciter 6 , 7 and 8 in the Ausführungsbeispie len according to FIGS . 1 and 2 each have a 90 ° waveguide elbow and other waveguide pieces, which transitions follow on the ribbon cable. In order to meet the requirement for extremely low unit costs, the exciters 6 , 7 and 8 are realized with the adjoining elbows and the rectangular waveguide pieces as recesses in an inexpensive manufacturable fine injection molded part composed of two plates 12 and 13 . The parting plane of these injection mold plates 12 and 13 is designated by 14 .

A problem with the motor vehicle distance warning radar is that interfering microwave radiation from oncoming vehicles that use the same warning system could also be picked up via the main lobe flank or the side lobes of the radiation diagram. This problem of suppressing the interference from oncoming vehicles can be solved in an advantageous manner by rotating the polarization of the exciters 6 , 7 and 8 by 45 °. The polarization of the three lobes 2 , 3 and 4 is then rotated through the same angle. The radiation from oncoming vehicles is thus theoretically invisible, because in the opposite direction of travel, a + 45 ° - a -45 ° polarization and vice versa. However, the antenna cannot receive orthogonally polarized waves. This effect does not occur with circular polarization, since, for example, a right-hand circular polarization also remains circular on the right when the vehicle is traveling in the other direction (for comparison: a right-hand screw never becomes a left-hand screw, regardless of the side from which it is screwed into a nut) . The implementation of a 45 ° linear polarization in conjunction with the other measures is an essential part of the antenna concept according to the invention.

A relatively simple way to rotate the Erregerpo larisation consists in rotating each of the exciters 6 , 7 and 8 itself by 45 ° about its longitudinal axis. Fig. 3 shows in a front view, which is partially cut away, of an inventive lens antenna arrangement, a three waveguide pathogens 6, 7 and 8 existing excitation system, in which the exciter 6, 7 and 8 are rotated about their longitudinal axis, that there is a polarization angle of 45 °. The exciters 6 , 7 and 8 can be simple open rectangular waveguides, or as shown in Fig. 4 in section AA, which have a particularly short design of a box horn 15 , ie a waveguide with a sudden cross-sectional expansion. In addition, they can also be designed as simple pyramid horn emitters. As already mentioned in connection with the description of the arrangements according to FIGS . 1 and 2, each of the exciters 6 , 7 and 8 is followed by a 90 ° waveguide elbow and further waveguide pieces 16 , which are followed by transitions 17 on the ribbon line 18 on a base board 31 with a very thin dielectric intermediate layer is applied.

Fig. 5 shows another way of rotating the exciter polarization. Here, the radiator apertures of the exciters 6 , 7 and 8 are not rotated in the longitudinal axis direction, but only the waveguide feeds 19 by 45 °. As the comparison with the arrangement according to FIG. 3 shows, a somewhat larger excitation aperture can be used with the same excitation distance. This reduces the glare at the edge of the lens. A certain increase in cross polarization on the flanks of the radiation lobe in the vertical and horizontal planes could be disadvantageous in the exciter principle according to FIG. 5.

It is pointed out that in the FIG. 4 form of the exciter as the box horn 15, the 90 ° waveguide elbow 20 adjoining it is visible in the sectional view. The polarization vector 21 of the electromagnetic waves is in the direction shown in FIG. 4.

Since when the exciters 6 , 7 and 8 rotate about their respective longitudinal axes, the radiation lobes 2 , 3 and 4 also rotate, a horizontally or vertically oriented elliptically or rectangularly edged lens 5 would no longer be properly illuminated in the case of an elliptical beam cross section. An overexposure occurs at the edges of the lens 5 , which causes interference and losses. In individual cases, it may therefore be more appropriate to choose the lens aperture and the exciter diagram in a circular manner, the lens diameter corresponding approximately to the long rectangular side of the original aperture. In the arrangement of FIG. 3, the Erregeröff voltage is therefore selected so as to give an approximately rotationally symmetric lobe. In order to nevertheless achieve different bundles of the radiation lobes 2 , 3 and 4 of the antenna in the horizontal and vertical directions, the lens contour is modified, for example in the vertical direction, in such a way that a suitable non-linear phase response results in this direction, which leads to the desired Beam broadening from, for example, 3 ° to 5 ° leads. In the lens version according to the arrangement according to FIG. 2, it may then be expedient to adapt the outer contour to the changed phase response; because only if no beam refraction occurs on the outer surface of the lens 5 , the advantages of this version are fully retained.

A radiation excitation system with an alternative form of exciter, namely a group of three patch antennas 22 , 23 and 24 , is shown in a schematic view in FIG. 6. This is a stripline antenna which consists of a conductive motherboard 25 with a very thin dielectric layer layer, on which rectangular metallic areas - namely patches 22 , 23 and 24 - are applied. These act as radiating elements. The supply of the Pat ches 22 , 23 and 24 takes place by lateral galvanic coupling via strip lines 26 , 27 and 28th The circuit board 25 with the patches 22 , 23 and 24 lies in the focal plane of the lens, that is to say parallel to the lens aperture. The strip lines 26 , 27 and 28 are connected by means of a transition 29 to a miniaturized integrated microwave circuit 30 , a so-called MMIC.

There now follows explanations of the function and the constructive Structure of the frontend.

The electronic circuit integrated in the front end contains a semiconductor component with a miniaturized integrated microwave circuit (MMIC) as the core. This also contains the electronic switches for switching between the three pathogens. In the case of patch pathogens, cf. exporting the approximate shape shown in FIG. 6, three lead lines 26, 27 and 28 by MMIC 30 directly through the transition 29 to the patches 22, 23 and 24. In the case of waveguides or pyramids, as is shown in FIG. 3, a special transition 17 for coupling from the ribbon cable 18 into the rectangular waveguide 16 is provided. The execution of such transitions is known in principle.

Since, given the very small dimensions, it is technically extremely problematic to establish a rigid galvanic connection between the MMIC and the further ribbon cable applied on a separate substrate ( 25 in FIG. 6 or 31 in FIG. 3), this is a flexible conductive connection provided between the two, which is fixed on one side by bonding.

In order to achieve high-frequency tightness, the entire focal plane outside of the waveguide openings with a metallic surface is sealed electromagnetically in the embodiments with waveguide exciters, so that no frequencies below the operating frequency can reach the electronic circuit. In order to achieve RF-tightness in the case of the patch exciter, it may be advisable to insert a piece of rectangular waveguide with corresponding couplings on both sides from the ribbon cables 26 , 27 and 28 and the space before the transition 29 in FIG. 6 to the MMIC 30 in addition to sealing the waveguides with a metallic surface.

An example of a constructive embodiment of a motor vehicle distance warning radar front end with an integrated lens antenna arrangement according to the invention is shown in FIGS . 7 and 8. In FIG. 7, an external perspective view is shown. The front end consists of a cuboid, z. B. manufactured in injection molding metal housing 32 , which on its front by a z. B. made of polystyrene, the lens 33 is covered. The lens 33 can e.g. B. by snap fasteners 34 as a lid. On a side wall 35 36 connector pins 37 z. B. cast, to which the power supply for the electronic switching elements in the housing 32 and lines for forwarding information from the housing 32 can be connected to an external computer in the motor vehicle. An example of the division of the components inside the housing 32 is shown in a partially cut oblique view in FIG. 8. It can be seen that the lens 33 rests on the housing 32 by means of a seal 49 such that a weatherproof cover of the housing 32 is provided. On the z. B. made of die-cast aluminum 38 , which is cast, for example, in the housing 32 , an electronics block 39 is glued. Electronic switching elements and possibly an ASIC module 40 with special protection are found therein or thereon. Also provided on a carrier MMIC 41 is provided in a protected manner. The exciters 42 , 43 and 44 with adjoining elbows and rectangular waveguides are realized as openings in a die-cast part composed of two plates 45 and 46 . Small conductive connecting strips 47 are interposed between the MMIC 41 and the electronics block 39 . The connections 48 to the cast connector pins 37 are also fixed by bonding on the electronics block 39 . The electronics block 39 , the ASIC module 40 and the MMIC 41 and the supply lines to them are protected and shielded by a metallized potting 70 .

In the exemplary embodiments described so far, radiation beams 2 , 3 and 4 are both transmitted and received via the respective switched-on lobe. Under certain circumstances, it may be cheaper to separate the transmitting and receiving antennas and, for example, to arrange them side by side. Since it is sufficient to carry out the direction selection when the signals are received, it is possible in the case of transmission to produce a wider radiation lobe of, for example, 10 ° in the horizontal direction. Such an embodiment is shown in a ge sectional view from above in Fig. 9. The left part of the antenna arrangement seen from the front forms a receiving antenna 50 which corresponds to the front end structure described with reference to FIGS. 1 and 2. Here, however, the inner surface of the lens 51 is flat, whereas the outer surface is curved and additionally stepped. The aperture of an adjacent transmitting antenna 52 is correspondingly smaller than that of the receiving antenna 50 . The transmitting antenna 52 has only one exciter 53 , but can otherwise be constructed according to one of the principles already described. Transmitting and receiving antennas 52 and 50 can be constructed according to the same principle, but do not have to be. In the metal housing 54 , which is lined inside and between the two antennas 50 and 52 with a damping layer 71 , the waveguide exciters 53 and 54 , 55 and 56 with the connecting elbows and rectangular waveguides as openings or depressions in one of two plates 57 and 58 arranged on a parting plane 59 composed fine injection molding. The lens 60 provided for the transmitting antenna 52 , which has a smaller aperture than that of the receiving antenna 50 , is shaped and stepped in a similar manner to the lens 51 of the receiving antenna 50 . An oscillator 61 is also installed in the transmitter part within the metal housing 54 .

Fig. 10 shows an example in cross-sectional representation, the radiation lobe 62 of the transmitting antenna 52 and the three radiation lobes 63 , 64 and 65 of the receiving antenna 50 of the arrangement of FIG. 9. In Fig. 11, the circular apertures when operating with 45 ° linear polarization Transmitting antenna 52 and the receiving antenna 50 of the arrangement according to FIG. 9 are exemplified. The aperture of the transmitting antenna 52 is denoted by 66 and the aperture of the receiving antenna 50 by 67 . An antenna set up after the separate transmit / receive operation for 0 ° / 90 ° polarization with rectangular apertures would have the formats shown in dashed lines, for example. The aperture for a transmitting antenna is designated 68 and the aperture for a receiving antenna 69 .

Claims (35)

1. Microwave lens antenna arrangement for motor vehicle distance warning radar with a radiation excitation system and a lens permeable to electromagnetic waves made of dielectric material, characterized in that the radiation excitation system for generating a left, a middle and a right radiation lobe ( 4 , 2 , 3 ) from three separately switchable, horizontally in the focal plane of the lens ( 5 ) side by side so arranged exciters ( 8 , 6 , 7 ) is that both the left and the right radiation lobe ( 4 , 3 ) with the middle ( 2 ) each in the flank area of the horizontal antenna pattern overlap, and that the lens designed as a converging lens has a short focal length and is provided with thickness and loss-reducing steps. 2. Microwave lens antenna arrangement according to claim 1, characterized in that the radiation lobes ( 2 , 3 , 4 ) in the vertical plane have a different, preferably stronger bundling than in the horizontal plane. 3. microwave lens antenna arrangement according to claim 2, characterized, that the exciter diagrams in cross section and the lens aperture are chosen circular, and that a different frets development in the horizontal and vertical plane is enough that the lens contour in the vertical or horizontal plane is modified so that in the respective suitable level gives a suitable non-linear phase response, the desired beam broadening in this plane leads. 4. Microwave lens antenna arrangement according to claim 2, marked by  a rectangular or elliptical lens aperture, the longer side in the plane with the higher club frets lung lies. 5. Microwave lens antenna arrangement according to claim 4, characterized in that the diagrams of the three exciters ( 6 , 7 , 8 ) each have different bundles in the two orthogonal planes. 6. Microwave lens antenna arrangement according to claim 5, characterized in that the three exciters ( 6 , 7 , 8 ) have rectangular apertures, the edges of which are vertical or horizontal. 7. Microwave lens antenna arrangement according to claim 5, characterized in that the three exciters ( 6 , 7 , 8 ) have square or circular apertures, different bundles being present in the E and H planes. 8. Microwave lens antenna arrangement according to claim 1, characterized in that the three exciters ( 6 , 7 , 8 ) of the radiation excitation system are designed and / or arranged such that they produce a 45 ° linear polarization. 9. Microwave lens antenna arrangement according to claim 8, characterized in that the three exciters ( 6 , 7 , 8 ) are each a rectangular aperture having waveguide exciters which are arranged side by side paral lel and with their edges rotated by 45 ° with respect to the vertical or horizontal direction . 10. Microwave lens antenna arrangement according to claim 9, characterized in that the waveguide exciter either as an open rectangular hollow conductor, as box horns ( 15 ), ie as a rectangular waveguide with a sudden cross-sectional expansion, or as a pyramid horn ner are formed. 11. Microwave lens antenna arrangement according to claim 8, characterized in that the three exciters ( 6 , 7 , 8 ) are each a rectangular aperture having waveguide exciters which are arranged side by side paral lel and with their longer edges in the vertical direction, but with the opposite by 45 ° twisted Hohllei tereinspitzeungen ( 19 ) are provided. 12. Microwave lens antenna arrangement according to one of claims 8 to 11, characterized in that for the case in which a spatial overlap of adjacent exciters ( 6 , because of the requirement for low lens radiation and the associated oversize of the horn radiator or waveguide exciter apertures) 7 or 7 , 8 ) would result in smaller apertures which do not cause any overlap, wherein dielectric rod radiators ( 11 ) which reinforce the excitation directional effect are then inserted into the radiator openings. 13. Microwave lens antenna arrangement according to claim 8, characterized in that the three exciters ( 22 , 23 , 24 ) of the Strahlungserregersy stems are three so-called patch antennas, ie line antennas, which consist of a conductive motherboard ( 25 ) with a very thin dielectric Intermediate layer exist on the rectangular metallic areas - the so-called "patches" - are applied, which act as radiating elements, that the feeding of the "patches" by lateral galvanic coupling via strip lines ( 26 , 27 , 28 ) it follows, and that the board with the "patches" in the focal plane of the lens ( 5 ), that is parallel to the lens aperture. 14. Microwave lens antenna arrangement according to one of the preceding claims, characterized in that the steps on the inside of the lens ( 5 ) are attached, and the outside of the lens has a smooth surface. 15. Microwave lens antenna arrangement according to one of claims 1 to 13, characterized in that the steps on the outside of the lens ( 5 ) are attached, and that in addition a low-loss radome window ( 10 ) with a smooth outer surface is arranged in front of the lens. 16. Microwave lens antenna arrangement according to one of the above arising claims, characterized, that by special choice of the lens contour the antenna beam behavior is optimized. 17. Microwave lens antenna arrangement according to one of the preceding claims, characterized in that one of the lens surfaces to reduce reflections
Changes. 18. A microwave lens antenna arrangement according to claim 17. characterized, that the changes are appropriately sized, evenly across the surface is distributed holes. 19. Microwave lens antenna arrangement according to claim 17, characterized, that the change through a surface layer is more appropriate Thickness with a low dielectric constant is formed. 20. Microwave lens antenna arrangement according to claim 16, characterized in that the lens contour is selected so that resulting image errors are reduced by the lateral offset of the exciter ( 6 , 7 , 8 ). 21. Microwave lens antenna arrangement according to one of the preceding claims, characterized in that the dielectric lens ( 33 ) and the radiation excitation system as well as downstream electronic switching elements are accommodated in a compact, for example cuboid-shaped housing ( 32 ) and form a so-called front end, that the lens also represents the weatherproof front cover of the housing, and that the housing has connections ( 36 , 37 ) on the back or on another side surface for supplying power to the electronic switching elements and for forwarding information signals from the housing to an external computer in the motor vehicle. 22. A microwave lens antenna arrangement according to claim 21, characterized in that the housing walls on the side of the lens ( 5 ) are coated with a microwave-damping layer ( 9 ) to avoid wall reflections. 23. Microwave lens antenna arrangement according to one of the preceding claims, characterized in that the dielectric lens ( 5 ) consists of polystyrene. 24. Microwave lens antenna arrangement according to one of claims 9 to 12, characterized in that the waveguide exciters ( 6 , 7 , 8 ) each have a 90 ° waveguide elbow ( 20 ) and then further waveguide pieces ( 20 ), which transitions ( 17 ) follow on ribbon cables ( 18 ). 25. Microwave lens antenna arrangement according to claim 24, characterized in that the waveguide exciter ( 6 , 7 , 8 ) with the adjoining bends ( 20 ) and the rectangular waveguide pieces ( 16 ) through depressions in one of two metallic or metallized plates ( 12 , 13 ) composite injection molding are formed. 26. A microwave lens antenna arrangement according to claim 21 or 22, characterized in that the electronic switching elements provided in the front-end housing ( 32 ) are formed by an integrated electronic circuit ( 39 ), the core of which is a semiconductor device with a miniaturized integrated microwave circuit ( 41 , 30 ), ie a so-called MMIC, in which electronic switches for switching between the three exciters ( 42 , 43 , 44 ) are also provided. 27. Microwave lens antenna arrangement according to claims 26 and 13, characterized in that three ribbon lines ( 26 , 27 , 28 ) are provided which from the miniaturized integrated microwave circuit ( 30 ) directly to the "patches" ( 22 , 23 , 24 ) of three patch antennas. 28. A microwave lens antenna arrangement according to claim 26 and one of claims 21 to 25, characterized in that three ribbon lines are connected to the miniaturized integrated microwave circuit ( 41 ), and that a special transition for coupling from the ribbon line is provided in the rectangular waveguide . 29. Microwave lens antenna arrangement according to claim 27 or 28, characterized in that between the miniaturized integrated microwave circuit ( 41 ) and the three ribbon cables attached to a separate substrate, a flexible conductive connecting ribbon is provided, which is fixed on one side by bonding. 30. Microwave lens antenna arrangement according to one of the An proverbs 21 to 26, characterized, that in the housing the entire focal plane with the exception of the hollow ladder openings with a metallic electromagnetic surface table is tightly closed. 31. A microwave lens antenna arrangement according to claim 26 or 27, characterized, that before the transition point to the miniaturized integrated Microwave circuit each a rectangular waveguide piece with corresponding double-sided couplings from the band lines is inserted, and that in the housing the room next to the rectangular waveguide pieces with a metallic surface is sealed. 32. Microwave lens antenna arrangement according to one of the preceding claims, characterized in that the radiation beam ( 2 , 3 , 4 ) that is switched on is both transmitted and received. 33. Microwave lens antenna arrangement according to one of claims 1 to 31, characterized in that only received radiation lobe ( 63 , 64 , 65 ) is received, and that for transmitting a special, only a single exciter ( 53 ) having lens antenna ( 52 ) is provided, which generates a wide circuit lobe ( 62 ), but is also constructed according to one of the principles according to which the only receiving antenna ( 50 ) is designed. 34. Microwave lens antenna arrangement according to claim 33, characterized in that the aperture of the transmitting antenna ( 52 ) is smaller than the aperture of the exclusively receiving antenna ( 50 ). 35. Microwave lens antenna arrangement according to claim 33 or 34, characterized in that the transmitting antenna ( 52 ) and the exclusively receiving antenna ( 50 ) are accommodated in a common housing ( 54 ), for which the same design features apply as for the simple housing ( 1 ) according to claim 21.