DE2248325A1 - DEVICE FOR FOCUSING WAVE ENERGY, IN PARTICULAR FOR ANTENNAS - Google Patents

Description

- ~ 'fatentanwAlte
DR. PHIL. G. NICKEL · DR.-ING. J. DORNER

8 MUNICH 15

LANDWEHRSTR. 35 POST BOX 10 *

__ TEL. (0811) 555719

Münohen, September 19, 1972 Attorney's files. I 27 - Pat. 40

Raytheon Company, 141 Spring Street, Lexington, Mass. 02173, United States of America

Device for focusing wave energy, especially for Antennas

The invention relates to a device for focusing wave energy, in particular for antennas. In detail concerns the invention electronically scanned antennas with a radiator arrangement each adjustable phase. It should be noted in advance that the invention basically involves a parasitic yeast deflector is provided at which a reflection of the scanning radiation takes place.

Known antenna systems with a radiator arrangement of adjustable phase in each case have a large number of elements. For example, 11,000 elements for an antenna are provided, which produces a very sharp-ray beam with an opening angle of the order of 1 degree, the radiation beam scanning a deflection through an angle of - 60 degrees may be experienced. Such an antenna is ideally suited for the pursuit of several targets, which can be highly variable with regard to the elevation angle and aziruth angle. As is known, such antennas are extremely expensive, large and heavy and Im

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Structure very complicated as far as this is the general economic ί borrowed application, for example the instruction of plug-in tools a runway. Apart from the aforementioned sewing parts, there is an antenna with an array of radiators adjustable phase ideal for briefing Plugzeug on a runway suitable as such an aircraft can be detected by the radar even if a there is a strong deviation from the desired approach path. The antenna can remain stationary while guide beams or tracking beams are generated in a variety of directions can to capture the different planes. It can be seen here that the usual design of antennas with an arrangement of radiator elements of controllable phase is significantly larger Search or detection capacity, namely a much larger area of the elevation angle and the azimuth angle, than for applications such as directing aircraft to a runway, is necessary ..

The invention aims to achieve the object of providing a device for focusing wave energy, in particular for Antennas to be designed in such a way that, despite a relatively simple and cost-saving structure, a very sharp directional characteristic is obtained. In particular, an antenna should have an arrangement of radiators each adjustable phase in the structure can be simplified and cheaper in such a way that the use for the instruction of aircraft on a runway is economically possible.

This object is in accordance with the idea underlying the invention by the phase position of individual beams of radiation relative to each other substantially independently changing, and thereby the direction of a resultant wavefront changing phase shifting arrangement and a ng at a distance therefrom and in the G _a of the Phasensohieberanordnung continuous beams located deflection device solved, which the direction of individual radiation rays impinging on them in relation to one another according to the respectively impressed

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Phase position changes so that essentially independent of the Direction of a beam associated with the deflection device whose directional characteristic remains the same.

An antenna arrangement built according to this basic principle comes with significantly fewer radiator elements than with the previous ones known antennas with an array of adjustable phase radiators were necessary. For a practical example are, for example, around 800 radiator elements compared to around 11,000 radiator elements in conventional antennas of this type provided with a comparable opening of the directional characteristic. To achieve a narrow beam Using a relatively small arrangement of radiator elements, a passive component is, for example, according to the invention provided in the form of a large reflector or in the form of a lens whose dimensions are so large, that the appropriate sharpness of the beam is achieved. A large reflector is preferably used. Through the The invention also relates to a system for instructing vehicles, in particular aircraft, along a predetermined path, for example, on a runway, proposed which contains a novel antenna.

In addition, they form expedient refinements and developments The invention is the subject of the accompanying claims.

A suitable arrangement is created which enables the generation of phase shift command signals enables the To control the phase position of the radiation emanating from the respective radiator elements of the arrangement in such a way that this Radiation ^ at a variable angle the surface of the reflector is scanned and reflected by the reflector as the desired, sharp beam, regardless of the shape of the beam and the shape of the opening with respect to the active radiation are retained. An area that is the most suitable Has regularity to this mode of action of the

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To generate antenna system is a conic section surface, in particular a hyperboloid of revolution and accordingly the surface of a reflector in a preferred embodiment of the invention is a hyperboloid of revolution.

A radiation target tracking or detection system which can work with all forms of electromagnetic radiation energy as well as with acoustic energy, according to the invention build in such a way that by means of signals generated by a computer, the required phase shift for the individual Radiator elements are generated to select the phase shift required in these individual radiator elements, such that the position and arrangement of the radiator elements relative to the reflector is taken into account, so that an antenna system manufactured with limited scanning range and with a sharp bundle of rays can be. It was also found that the arrangement radiating elements preferably corresponding to a curved surface or in a simple case corresponding to a cylindrical surface should be provided in order to facilitate the formation of the scanning beam.

It should also be emphasized that, according to a preferred embodiment of the invention, the control of the phase shift although it takes place in such a way that the wave front of the radiation emanating from the aforementioned radiator elements is approximately - 50 degrees while the direction of the is steered by the reflector outgoing beam is only deflected by -10 degrees, which is due to the concave shape of the surface of the reflector based on this preferred embodiment and the arrangement of the radiator elements relative to this surface. One with the Features of the invention equipped antenna has the effect of reducing the scanning angle of the radiation beams, while the opening effective for the radiation and the directional characteristic compared to the arrangement of radiator elements can even be enlarged.

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The following are exemplary embodiments with reference to special Advantages and significant features explained in more detail with reference to the drawing. Show it:

Figure 1

Figure 2

Figure 3

figure k

characters
and 6

Figure 3 is a perspective view of a radar tracking system with an antenna having the features of the invention and with further components of the radar system, which are shown as a block diagram,

another embodiment of the invention, at which the passive reflector is replaced by a passive lens,

another exemplary embodiment of the invention, in which, in contrast to the aforementioned embodiment, an active lens with a A plurality of phase shifters is provided along with an active reflector, which in similar Way contains a large number of phase shifters,

a graphical representation to explain the geometrical relationships between the individual Elements for the purpose of deriving the mathematical expressions used by the calculator in the system of Figure 1 for determining the phase shift command signals for the individual Phase shifters must be used in the antenna according to Figure 1,

Figures showing two types of distortion of the active antenna aperture that are duroh an incorrect adaptation of the curved reflector surface to the wavefront or to the surface the same phase position of the radiation caused by a certain arrangement of phase shifters of the antenna system according to Figure L impinges on the reflector,

) 0 <) ii I B / I 0 ί) 3

characters
7A and 7B

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

6 22A8325

an illustration to explain the distances

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and the dimensions of components of an antenna system with the features of the invention according to an advantageous embodiment in Upright and in side view,

a geometrical representation, which is used to set up a beam control program is appropriate and to determine the coefficients for the Reohner-controlled phase shift for beam control in an antenna system nit serves the features of the invention,

a block diagram of a beam control unit Direction for generating the control signals influencing the phase shift for a antenna according to the invention,

a schematic circuit diagram of the control circuit for the phase shifters in the antenna system with the features of the invention,

Time diagrams to explain the processes in the circuit according to FIG. 10,

a schematic front view of a lens for an antenna with the features of the invention, being the distribution of heating within the lens and the required width of the Pulses are indicated which are used to generate an additional flux in the magnetic material the phase shifters of the lens are necessary to the effect of the different heating the phase shifter to compensate and finally

a timing diagram for the system shown in FIG.

J 0 f) HI Γ) / I 0 9 Ί

In Figure f, a control system 30 is shown, which is able to derive data about a radiation source and which contains an antenna arrangement 32 with the features of the invention, this antenna in the present embodiment as a radiation source detects an aircraft 34, which is on a near the. Runway 36 located at antenna 32 is to land. Antenna 32 includes a reflector 38, a lens 40 and a horn 42 is directed from which radiation through the lens 40 through the reflector 38, from where it is reflected to the plane side 34 in this embodiment of the invention. The reflector 38 is significantly larger than a region struck by the radiation 44, which is hereinafter referred to as the active opening 46, in such a way that the active opening 46 can carry out a scanning of the reflector 38. In addition, the active opening 46 is larger than the lens 40, so that a sharper beam and a sharper directional characteristic of the antenna 32 can be achieved. The surface of the reflector 38 is curved in the manner still to be described, in such a way that active openings 46 of essentially constant shape with essentially constant radiation distribution with respect to the viewing direction along the axis of the beam emanating from the reflector regardless of the position of these active openings 46 on the reflector 38 can be obtained. Such equality of the active openings 46 is very important in order to obtain precise data about the position and the directions of the aircraft 34 which are to land on the runway 36 ′.

The lens 40 contains regions which impress different amounts of phase shift on the incident radiation, with these phase shifting areas of a multitude of Phase shifters 48 are formed which are oriented normal to the inner surface 50 and the outer surface 52 of the lens 40. Of the Horn antenna 42 has such a distance from the lens 40 that a curved or arcuate wave front, which from the horn antenna 42 goes out when hitting the inner surface of the lens

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preferably essentially in this curved inner surface comes to rest. The energy is transferred from this wavefront to each of the phase shifters 48 and is planted through them Phase shifter 48 continues to exit again at outer surface 52 of lens 40. The phase shifters 48 preferably have Holding properties, whereby a Perritwerkstoff nit an im essentially rectangular hysteresis is used, so that electrical signals to control the phase shifter via lines 54 only need to be fed instantaneously to adjust the phase shift, which of the propagating through each phase shifter 48 Energy is to be impressed to adjust where each phase shifter 48 retains the phase shift property, until further control signals are supplied via lines 54. For example, phase shifters 48 can each contain two windings, which are so around the ferrite material are laid that one of these windings is used to reset the ferrite material to a reference state of magnetization can be, while the second winding with a voltage pulse of predetermined duration can be applied to a certain magnetization state in the ferrite material to generate, which leads to the desired phase shift. Explanations in this regard are given below in connection given with Figure 10.

The phase shift signals generated in the manner indicated below are fed via the control lines 54 for setting the phase shift of each phase shifter 48 in such a way that the radiant energy emitted by the outer surface 52 of the lens 40 reaches a part of the reflector 38 in a predetermined direction, from which it is in is reflected in a desired direction. The phase shifters kti are preferably moved sufficiently close together that a grid-like arrangement of maxima and minima does not result in a grid-like arrangement of maxima and minima within a range of -50 degrees, i.e. over a range over which the radiation emanating from lens 40 is to perform a scan. The resulting bundle of rays 56,

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which is generated on the concave Fläohe of the reflector 38 by reflecting the incident radiation, but performs only a scanning movement over a Winkelbereioh of - 10 degrees duroh so that. the lens 40 and the reflector 38 apparently cooperate in the sense of reducing the scanning angle. Despite the limited scanning range of the antenna 32, it is possible to track or guide aircraft 34 in the general vicinity of the approach path to the runway 36 by simply tracking the radiation beam 56. The system 30 sprays both on a radiation beam 56 due to a reflection on the aircraft 34 and on the radiation generated within the aircraft 34, for example from a repeater beacon.

A base 58 has a support structure 60 for support of the reflector 38 connection, the support structure 60 also giving the reflector 38 a certain dimensional stability, itself when wind forces are effective. The base 58 is with a side arm 62 provided on which an arm via a hinge point 66 64 is stored. The arm 64 is like through the streaked lines 68 and 70 is indicated, structurally connected to the lens 40 and the horn antenna 42 in order to give these components a certain relative position to the reflector 38 to keep. This predetermined position can be changed by means of a motor 72, which in on can be energized in a known manner, not shown, to pivot arm 64 about side arm 62; so that the distance between the lens 40 and the reflector 38 can be changed. It should be mentioned in this context that the pivoting of the arm 64 to the side arm 62 expediently has an adjustment effect, duroh which the width of the beam 56 and its active opening 46 can be changed.

The horn beam-r 42 is preferably designed for single-pulse feeding and can contain four wave guides, which with an electronic. Unit 74 over a group of four Wave lines are connected in Figure 1 by the lines

- ο

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76 are indicated. Each of the lines 76 carries a portion of the signal sent out or received by the horn antenna 42 and with respect to the received signals, there is a phase difference between the signals from each of the lines 76 information relating to elevation angle deviation and azimuth angle deviation of the aircraft 34 from the center of the beam.

The electronic unit 74 contains a waveguide comparator 78, a transmitter 80, a receiver 82, a transceiver switch 8Ai ₁ which is in the sum channel of the waveguide comparator 78 and the waveguide comparator 78 with the transmitter 80 and the receiver 82, furthermore a signal processing unit 8V, a Reohner 86, a beam control unit 88, a playback device 90, a control desk 92, via which an operator can input data that is displayed on the playback device 90 and processed by the Reohner 86, and finally a timer unit 94, which transmits clock signals over the lines 96, 98, 100 and 102 in order to time-control and synchronize the respective processes in the beam control unit 88, the playback device 90, the receiver 86 and the signal processing unit 84.

The waveguide comparator 78 and the horn radiator 42 are advantageously designed as a single structural unit, which is designed as a multiple mode single-pulse radiator and comparator, such as in the publication by Peter Harmon, "Transactions of the Institute of Radio Engineers Professional Group on Antennas and Propagation ", September 1961, is described, with higher order vibrations propagating in a horn antenna, for example the antenna 42. It is known that such a construction has essentially the same spreading in both the sum and difference characteristics. The comparator 7H contains, for example, the known Hybril-Miiichet-, U hut which ilie lines ~} ύ with one another

M) ¹ IH

are to perform the arithmetic operations ssma - formation of the difference between the signals on the lines "? 6 for the guidance of the elevation angle difference signal for the line i © 4 and the Azlmuthwinkel difference signal for the line 1 © 6, while the sum of the Signals from all four lines 76 * form the signal of the aforementioned sum channel for line 108. The transmit / receive tube 8%, which can be of conventional design, allows the signal from the transmitter 8C to be passed on via the lines iiO and 108 to the waveguide comparator 78 and from there to the horn antenna 42, while the receiver 82 is separated from this signal conduction path be a conventional three-channel receiver, which sends HiJhenwinkel and Amimuthwiankel error signals via line 112 to the computer 86, which then sends these data to the ne The external alignment of the beam 56 is evaluated for the purpose of tracking the aircraft 34. If several aircraft are in the area of the bundle of rays 56, then the line 113 can be supplied with ready-to-stop signals which enable the individual aircraft to be tracked in certain areas. Moreover, that is "weiterbehandclt, Iwiehmbare signal in the signal processing unit 84V which I" of the sum channel pul * compression circuit "n contained, may be able to make a distinction between aircraft that together are very close range as standard, or Signalverarbeitungseiniielt 84 ^a can make use of the correlation technique, in which a low-power double of the transmission signal is obtained as a reference signal via the line 114 and is used for a correlation in order to be able to distinguish relatively closely spaced aircraft. The area information, which is determined by the time relationship of the received signal and the clock signal on the line 102, arrives via the line 116 to the computer H ¹ S ₉ BIe control of the StrahlemMinder 5 & © rialgt via Winkelelnstellurags command signals, soft v © m dean ffleasliner 86 and via line HB to the beam control

-IS-

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unit 88 can be transferred. The beam steering unit 88 generates depending on these angle adjustment signals, the group of aforementioned phase shift command signals which The individual phase shifters 48 are supplied via the lines 54 will.

It is often desirable to have an air surveillance radar device 120 with an antenna 122 and a radiator or feeder 124, which rotate around a base 126 to the position coordinates of an aircraft, namely distance, elevation angle and azimuth angle as well as the derivatives thereof via to deliver a line 128. A known coordinate converter 130 calculates these values of the position coordinates into a group of values which correspond to the position of the antenna 32. These rearranged coordinate values are then sent over the line 132 to the control panel 92 to be transmitted over the line 134 to get into the playback device 90 so that the position of the aircraft in the vicinity of the runway 36 can be displayed. aside from that the converted values reach the computer 86 via the line 136, thereby enabling the tracking of such an aircraft is initiated according to the selection made on the control panel 92.

In Figure 2, another embodiment is one with the features The antenna equipped with the invention is shown, which has a horn antenna 138, a lens 140 with a plurality of phase shifters 142 for aligning the output from the horn 38 Radiation and a lens 144 contains, welohe made of ceramic material or plastic or from each other parallel waveguide sections 146 located at a distance from one another are produced, which are indicated schematically, lens 144 directing radiation that has passed through lens 140. The lens 144 is convex in such a way that that the radiation rays which strike the central part of the lens 144 are opposite to the radiation rays, impinging near the edge of the lens 144, a delay occurs.

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drive to achieve the aforementioned alignment or collimation. Note that the lens 144 and the lens 140 interact in a corresponding manner, as in the embodiment according to FIG. 1, the reflector 38 and the lens 40.

In Figure 3 is yet another embodiment of the invention shown, oei which the lens 40 according to Figure 1 by a Auxiliary reflector 148 is replaced, which has an arrangement of phase shifters 150 contains to 'the horn 152 from It directs incident radiation onto a reflector 154, the auxiliary reflector 148 controlling the individual radiation beams effected in a corresponding manner, like the lens according to FIG. 1. In the two shown in FIG. 2 and FIG Embodiments, the individual components of the antenna are supported and held by mounting structures known per se, but which are not shown in the drawings. Furthermore, it goes without saying that the reflector 154 according to FIG a lens corresponding to the lens 154 according to FIG. 2 'can be replaced.

As mentioned earlier, it is a fundamental property the device according to the invention that for example the reflector 38 according to FIG. 1 is irradiated in such a way that the active openings their shape and uniform irradiation regardless of their Maintain position on reflector 38. This is achieved by selecting a corresponding curvature of the reflector 38 and by corresponding Selection of the mutual position and alignment of the reflector 38, the lens 40 and the horn antenna 42 is achieved. A method for determining the curvature and the named positions is given below.

The reflector 38 is much larger than the lens 40 and is arranged within the near field of the lens 40, ie it is located at a sufficiently small distance from the lens so that the principles of Fresnel ¹ see optics for calculating the beam 56 are valid from the

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Effect of the lens 40 with the reflector 38 results, these components essentially as a single focusing element are effective, the lementen ordered from two parts, namely the lens 40 and the reflector 38. Here is a distinction compared to previously known systems in which a large number of microwave lenses or other focusing elements were provided in order to achieve a desired focusing or alignment of a beam. With previously known Systems were focussing in one. Trächtliohen distance, in the Frauenhofer area or in the far field area located while the components of the present focusing system are located in the Fresnel area or in the near field.

The lens 40 is provided with a curved surface in order to keep the radiation as small as possible, which is intended to reach the reflector 38 from the phase shifters 48 at a grazing angle. In this way, the effects of mutual coupling between the various phase shifters 48 are kept low and an increased output of the radiated radiation is obtained, since this radiant energy can be emitted in a direction essentially perpendicular to the end face of the phase shifter 48, so that a reduced gain in the Directional characteristic of each phase shifter 48 in the direction of a grazing angle is substantially avoided. The curvature of the lens 40 also facilitates the interception of the radiation emanating from the horn antenna which leaves the horn antenna 42 essentially in the radial direction, with a curved, essentially spherical wave front being formed which can be picked up particularly easily by the phase shifter when the phase shifter is used of the lens 40 are located with their receiving surface on a curved surface. According to a preferred embodiment, the distance between the lens 40 and the horn antenna 42 is chosen so that the lens lies in the far field of the horn antenna 42 (the distance here is slightly greater than <, M / A, where D is the diagonal of the opening of the horn antenna 42

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and Λ mean the wavelength of the emitted radiation).

When choosing the surface curvature of the reflector 38, it is expedient to use an area that is easy to use mathematical expression to describe is, 'for example a Hyperboloid surface of revolution in which a whole group of curved surfaces can be characterized in a simple manner by two parameters, for example by the eccentricity and the axial distance between a focal point and the hyperboloid. By simply varying these parameters as well as by changing them the relative positions of reflector 38 and lens 40 to one another Repeated subroutines can be performed by a computer to locate specific points on the lens 40 to assign corresponding points in the active opening 46, for example points along a vertical line and points along a horizontal line such that the general shape of the active opening 46 can be seen without the antenna 32 needs to be made practically. This assignment of Points on lens 40 to points on the active aperture of the reflector 3 & will now be described.

If you look at Figure 4, you can see the individual construction lines to carry out the assignment. The first step is to determine the size, location, and placement of the array

of phase shifters in the lens 40 of Figure 1, which here is indicated by a rectangle 156., The reflector 38 is in FIG. 4 through the trace or section line of a hyperboloid surface 158 shown. This arrangement is the same as with the The embodiment according to FIG. 1 shows the rectangle 156 opposite the hyperboloid surface 158 offset so that the beam reflected from the hyperboloid surface 158 does not hit the rectangle 156 can hit. First, a central beam of rays 160 and two extreme bundles of rays 162 and 164 considered in more detail which bundle of rays of radiation in a non-deflected State, in a state of deflection in the azimuth direction of + 10 ° and in a state of deflection in the azimuth direction of

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- represent 10. The method and the individual steps are shown here for an azimuth plane, while of course repeat the same procedure for a plane corresponding to a given elevation angle.

The bundle of rays 160 is through an upper ray 166 and defines a lower beam 168. The beam 162 is delimited by an upper beam 170 and a lower beam Ray 172 while finally the bundle of rays 164 bounded by an upper beam 174 and a lower beam 176 will. Beams 170 and 172, beams 166 and 168, and beams 174 and 176 are each equidistant from one another. It is assumed that the beams 160, 162 and 164 from external radiation sources onto the hyperboloid surface 158 meet, the radiation meeting in a direction corresponding to the arrows drawn on the beams 166, 170 and 174 propagates. The beam 162 irradiates an active opening 178, which corresponds to the active opening 46 according to FIG and the bundle of rays 64 irradiates an active opening 180 in a corresponding manner.

To determine the boundaries of rectangle 156, the ray 170 extended to the hyperboloid surface 158 where the ray experiences a reflection as new ray 170A and ray 166 is in a corresponding manner at the hyperboloid surface 158 as Ray 166A reflects and intersects ray 170A at point 182. Point 184 results in a corresponding manner as the intersection of rays 168A and 176A, which latter respectively the reflected rays to the incoming rays 168 and 176 are. Points 182 and 184 represent the boundaries of the front face of the array of phase shifters which are symbolized here by the rectangle 156. While rays 170 and 172 are substantially parallel, are the reflected rays 170A and 172A generally not parallel, since, as can be seen from FIG. 4, the angles of incidence and reflection for the various rays correspond to the

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associated contact point on the hyperboloid surface 158 vary, It should be noted that the specified construction method for conical section surfaces any eccentricity and focal distance as well as for electromagnetic radiation energy, sound energy and for Light is valid. (For example, ellipsoids have an eccentricity less than one and hyperboloids an eccentricity greater than one).

The next part of the geometrical construction in assigning the points is that rays are drawn from each point on a line 186, which is the connecting line of points 182 and 184, in the direction of the hyperboloid surface 158, around the ray bundles 160, 162 and To generate ΙβΊ , which now run in a direction from the hyperboloid surface 158 to the outside. The line 186 represents the end face of the arrangement of phase shifters k8 contained in the lens hO according to FIG. 1 in a cross section corresponding to an azimuth plane.

Before the description of drawing rays to achieve the point assignment is continued are two examples of records with reference to Figures 5 and 6 explained and the The actual geometry of the arrangement according to a preferred exemplary embodiment can be seen from FIGS. 7A and 7B.

Looking at FIGS. 5 and 6, two recordings can be seen of reflection points on the hyperboloid surface 158, the reference numeral 188 denotes these reflection points and are located within active openings 178A and 178B, respectively are. Both active openings are shown in the drawing figures Illustration of an example distorted in order to clarify the effect of an incorrect selection of the hyperboloid surface 158. the active openings 178A and 178B are shown in two directions, both in the direction of the elevation angle and auoh

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in the aziruth direction to show that although there is a symmetry the active opening can prevail with respect to a vertical plane, but this is not necessarily also a symmetry to the azimuth axis means. The distortion can easily be seen in FIGS. 5 and 6 by comparing the shape of the active openings 178A and 178B with the desired shape of the active opening 189 indicated in dashed lines. This distortion would clearly lead to an undesirable result in the single pulse tracking system because of the phased midpoint for the four quadrants 190A to 19OD opposite the center the active port 178B is reversed. When deriving the difference frequency for the elevation angle error signal of the single-pulse method For example, in the case of the active opening 17BB in the distorted shape, a misalignment of the aiming system results and this error varies with elevation angle as the distortion of the active aperture 178B varies with its location Opening on reflective surface 158 of the hyperboloid changes.

Reference is now made to FIGS. 7A and 7B, in which two schematic illustrations of the antenna 32 according to FIG. 1 are shown, on the one hand a horizontal view or plan view in a representation with the coordinates X and Z and on the other hand a side view in a representation with the coordinates X and Y. The Heflektor 38 is shown schematically as a trace of a hyperboloid area sector, üie schematic illustrations of the reflector 38, the lens kO and the horn antenna 42 are superimposed in the illustrations to the dimensions and the arrangement of the components according to A preferred embodiment of the invention for generating the active opening 46 according to FIG is. The reflective surface of reflector 38 is shown in the drawing figure

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given by an equation of a hyperboloid, of which, the reflector surface is simply a sector. All dimensions in the drawings are given in inches. The one in the equation Occurring coordinates X, Y and Z relate to coordinates in the graphic representation. The reflector 38 extends in a horizontal plane from the value Z = 43 inches or 109.2 cm up to. a value of Z = 153 inches or 386.5 cm and in the vertical plane from a value of Y = - 62 inches or 157.5 cm to a value of Y = + 78 inches or 198.3 cm. The lens 40 and the Horn antennas 42 have a common axis 192 which relative to the X-axis in the manner shown in the drawing around is inclined at an angle of 47.9 °. The endpoints of the front face or the surface of the lens 40 facing the reflector 38 are in the horizontal plane by the coordinate values X = 60.31 Inches or 248.5 cm and Z = 18.52 inches or 47.1 cm for the one end point and by the coordinates X = 80.52 inches or 204.8 cm and Z = 36.80 inches or 93.5 cm. The radiating opening of the horn 42 is from the rear surface of the Lens 40 measured over a distance of 26 inches or 66 cm on axis 192, removed. The lens 40 is curved, as indicated by the auxiliary representation within FIG. 7A at 194 is, wherein the lens 40 is shown here schematically within a plane which contains the axis 192 and perpendicular to X-Z plane stands. In the auxiliary representation 194 is the radius of curvature the lens is drawn 40 by 65 inches or l65 cm, where the center of curvature the coordinates Y = O, X = 114.01 inches or 290 cm and Z = - 20.55 inches or - 52.2 cm. The lens 40 thus has a front surface and a rear surface, which in each case the shape of sections of a circular cylinder jacket surface own. The vertical coordinates of the lens 40 are shown in the X-Y plane, with the upper edge of the Lens 40 the coordinate values Y = + 20 inches or 50.8 cm and the lower edge of the lens 40 the coordinates Y = - 20 inches or 50.8 cm. In the horizontal or azimuth plane, the antenna 32 generates a scanning radiation beam within one

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Arc areas of 20 °, the center being located at an angle of 3.4 relative to the X axis, as shown in FIG. 7A. In a vertical plane or in a plane corresponding to the elevation angle, the antenna 32 effects a scan over an arc region corresponding to an angle of 15 ° _f of which about 6 are below the horizontal plane, while about 9 ° are scanned above the horizontal plane.

The desired shape of the antenna components in accordance with the illustrations of Figures 7A and 7B was obtained in the manner described above by a Strahlenaufzeiohnungeprogramm using a computer, Duroh continuation of Strahlauf be drawing program, the coordinates of the reflection points along the hyperboloid 158 of FIG h using the plane equation of the hyperboloid can be calculated without difficulty. If, for example, the rays of the bundle of rays 162 are constructed, the rays which emanate from the lens, which is represented by the rectangle 156, are found by an iteration process (see Newton ¹ approximation method) in which a ray starts from a point line 168 is drawn in a direction approximately parallel to ray 170A to a point with hyperboloid surface 158, after which a second ray is drawn from this intersection in a direction parallel to ray 170. The angle of incidence and the angle of reflection of these two rays are then compared with one another, after which the two rays are drawn again to a slightly displaced point of impact on the hyperboloid surface 158 and the angle of incidence and the angle of reflection are compared again. This process continues until the two angles are substantially equal. Then another pair of rays, one of which is roughly parallel to the ray 170A and the other parallel to the ray 170, is drawn from another point on the line 168 to another point of incidence on the hyperbolic area 158 and that The iteration process is continued until the point of intersection with the Ilyperboloid surface 158 occurs

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a point comes to rest at which the equality of the angle of incidence and the angle of reflection applies. The result is the recording of these points of impact or intersection, such as they are indicated in FIGS. 5 or 6 at 188. The calculation program is now based on a repetition of the beam construction program set, but for a hyperboloid 158 with a different eccentricity and / or cup distance. Different hyperboloid areas are then displayed in the computer program 158 used with different parameter values, until an optimal set of values is reached as shown in Figures 7A and 7B.

It should be noted in this connection that the curvature of the lens 40 is not yet taken into account in the beam construction program because a cylindrical lens has been used which has zero curvature in the azimuth or horizontal plane owns. Essentially a similar recording process becomes however, carried out for the plane or vertical plane corresponding to the elevation angle, a mathematical expression being introduced which touches the curved surface of lens 40 and which in the beam design program accordingly is used.

Referring now to FIGS. 1 and 8 again, the beam control signals are fed from the beam control unit 88 via the lines $ k to the phase shifters 48 after they have been generated by the beam control unit 88 in accordance with a program which has been derived from a beam construction method, such as it is explained in FIG. The reflector 38, the lens 40 and the horn antenna 42 according to FIG. 1 are also shown schematically in FIG and then get to the aircraft 34 depends on the angle of the

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Beam 56 or on the angle of the wavefront, which is drawn in sohematiseh and is denoted in FIG. 8 by the reference number 196. A second wavefront 198 that appears in Figure 8 is shown as a broken line, propagates in a direction which is different from the direction of the wave front I96 is different.

FIG. 8 shows two bundles of rays, the first of which belongs to the wave front 196 and contains the radiation beams 200, 201 and 202 and the second of which belongs to the wave front 198 and contains the radiation beams 203, 204 and 205. Each of the six radiation beams mentioned is reflected at the reflector 38 and, after reflection, bears the additional reference letter A and as such a beam passes through one of the phase shifters 48 of the lens 40 to the horn antenna 42. Regarding the three radiation beams 200, 201 and 202 is to note that these are in phase with one another at wavefront 196. However, the electrical path length, measured in wavelengths, for beam 200 plus beam 200A is different from the electrical path length of beam 201 plus beam 201A or beam 202 plus beam 202A. The phase difference on these paths of radiant energy between the horn 42 and the wavefront 196 is compensated for by the phase shifters 48, which impart an additional phase shift to each radiation beam in order to make the phase of the individual beams at the wavefront 196 the same. The size of the phase compensation to be applied by each phase shifter 48 to achieve phase equality can easily be determined by means of a Reohner programmed according to a beam construction program, this program being based on the positions and orientations of the individual components of the antenna 32 and the wavefront I96. These calculated values of the phase shift are precisely those values which are necessary to generate a beam having a wave front corresponding to wave front 196.

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In the same way, a group of phase shift values Taezüglioh der Welleniront ± 98 is calculated. The phase shifters 48 realize these phase shift values modulo 360 °. the Phase shifts for other beam directions are determined by the computer program simply by the fact that the wave leniront 196 is rotated around point 208 in other directions, as carried out, for example, for the wavefront 198, where then the calculation program is repeated. .._.-

The subroutine indicated above is repeated for a sufficiently large number of directions of the wavefront 196 to be able to produce a graphic representation in which the phase shift of each of the phase shifters 48 is plotted over the beam direction. Such a graphical representation is produced for each phase shifter 48 as a function of the elevation angle at azimuth angle zero and a further graphic representation is produced for each phase shifter 48 as a puncture of the azimuth angle at elevation angle zero. This pair of graphical representations or characteristics for each phase shifter 48 can be represented fairly precisely by a polynomial in the form of a power series, namely ⁰ ^ - C. ^ + Cg ^ & ■ + + O / c ^ ~ * ^ ~ 4k τ "* "6 ~ k ^ P " where (S> the azimuth angle and φ the elevation angle and ⁰ ^ is the total amount for the phase shift, which is impressed by the k-th phase shifter 48, in the preferred embodiment of the antenna equipped with the features according to the invention 32 824 phase shifters 48. The symbols C. _fe -G- denote a group of five constants for each of the k phase shifters 48. As can be seen from the above equation, the terms including the elevation angle and the azimuth angle are separate and terms with both sizes do not occur.

It has been found that the expressed by the above basic equation Approximation of the phase shift actually provides a sufficiently accurate prediction of the amount of phase shift required O ^ allows which of the k-th phase shifter

- 23 309 8 15, / 109 3

must be generated, so that then 'if each phase shifter produces the required phase shift in accordance with the basic equation, the beam 56 of Figure 1 with respect to elevation angles and azimuth angles using the Nährungewerte £ p and φ is controlled from the above basic equation.

In order to determine the exact angular deflection of the beam 56 with respect to that which results from the above basic equation, the antenna 32 is simulated by a computer, the proportional phase shifts of all phase shifters being added up to calculate a resulting beam 56, which is derived from the proportional phase shifts of all phase shifters 48 results, which in each case generate the phase shift assigned to them, calculated in accordance with the above basic principle. The elevation angle components and azimuth angle components of the direction of the bundle of rays 56, as calculated by this computer when simulating the antenna, are then compared with the elevation angle components and azimuth angle components, namely with the values Φ and £> , which are used in the above-mentioned basic equation to determine what correction must be made to the beam steering command signals. The necessary correction is calculated for different directions of the beam 56 and it has been shown that the corrections can be expressed by an empirical equation which is evaluated within the beam control unit 88. The correction of the beam control command signals which are output on the lines 54 is carried out by means of the beam control unit 88 in such a way that each of the angle information signals received via the line 118 is changed into a slightly different angle information signal by adding the necessary angle correction as it is within of the beam control unit 88 has been calculated in the manner to be described, so that the beam control command signals which are output to the lines 54 have such values that the beam 56 is steered in the desired direction.

309815/1093

Detailed representations can be found in FIGS. 9, 10 and 11 the beam control unit 88 according to Figure 1, indicating the connections to the driver circuits for the Phase shifter 48 according to FIG. 1. FIG. 9 illustrates the beam control unit 88, while FIG. 10 shows the driver circuits 250 for generating the magnetic flux in the ferrite material the phase shifter 48 shows, such a driver circuit 250 being assigned to one of the phase shifters 48 is. The phase shift of each of the phase shifters 48 of the lens 40 is set to a suitable value depending on the drive signal of the associated driver circuit 250, the driver signals from the timing diagram shown in FIG. 11 being increased can be found.

Referring to Figure 9, the beam control unit 88 receives an angle command signal via line 118 and clock signals via line 96. Both signals were previously used in connection with FIG already mentioned * Also, the group of output lines is 54 which, as already shown in FIG. 1, connect the beam control unit 88 to the individual, associated phase shifters 48. To the clock signals on the line 96 it is to be said that these different time signals and synchro- contain nisationsimpuise as they are generally known for digital devices and which, for example, to the shift registers, to the logic control circuits, to the pulse generators and get to the arithmetic units. The use of such. Clock signals or timing signals are well known and accordingly the line 96 is shown only symbolically in FIG. which ends at the dashed border of the blook symbol of the beam control unit 88 'without the connection for the individual components of the beam control unit 88 would be drawn.

The beam control unit 88 includes a compensator 252, whence any angle information signal appearing on line 118 changes so that an angle correction is made as previously in connection with the beam construction

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according to FIG. 8 and the determination of the phase shift values accordingly the above-mentioned basic equation. the Corrected angle adjustment signals appear on line 254. Compensator 252 contains an on the sign of the Angle as a function of the elevation angles and the azimuth angles Respective unit 256, a memory * 25 * 3 and an arithmetic unit 260, soft to the angle information signal of the line 118 adds a correction expression from memory 258, in order to be able to output the corrected angle information signal via line 254. The required correction expression will be derived from the memory 258 by means of an address signal, which is fed via the line 262 as a function of a calculation in the unit 256 responding to the sign of the angle on the basis of a formula in which the magnitudes of the height - angle and azimuth angle can be used.

The required phase shift, which must be communicated to the radiation emanating from the horn antenna 42 by each of the phase shifters 48 according to FIG executes the calculation rules contained in the above-mentioned basic equation, namely the multiplication of the elevation angle and azimuth angle with the corresponding constants C ₂ and C., the squaring of the elevation angle and the azimuth angle and the multiplication of the respective square values with the constants C_ and C_ and finally the summation the-

3 5

These expressions with the constant C., The corresponding values of elevation angle φ and azimuth angle 0 reach the arithmetic unit 264 via the line 254 and the required values of the phase shift, which are calculated by the arithmetic unit 264, appear as three-digit binary numbers on the lines 266A to C, the individual digits appearing on one of the lines 266A to C. A storage unit 268 stores particular groups of constants C. to C ₁ -, with one of these groups each corresponding to one of the phase

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slide 4.8. is assigned according to Figure 1. In the preferred embodiment, in which 824 phase shifters 48 are provided, there are therefore 824 groups of constants G. to C-, welohe a storage space of 44 places each for. make each phase shifter 48 necessary. The arithmetic unit 264 must therefore have the Repeat the above calculation 824 times and each calculation process uses that group of constants C. to C-, which belongs to the phase shifter 48 in question. The coordinate -ring these bills and also addressing the correct ones Groups of constants in the storage unit 268 are carried out by a logical control unit .270, which communicates with the arithmetic unit 264 and to the storage unit 268 via lines 272 and 274 in FIG Connection. After the logical control unit 270, the storage unit 268 and the computing unit 264 for calculating the Phase shifts can, for example, be of a type known per se and can be designed as digital units, are unnecessary a further description of these components of the circuit.

Since all the rays of the beam 56 according to FIG. 1 are simultaneously must be controlled in a certain direction, it is necessary that each of the phase shifters 48 has its phase shift control signal received via line 54 at the same time. The calculated values of the phase shift, which for each of the phase shifters 48 on lines 266 A through C for the individual phase shifters must occur in sequence, accordingly are temporarily stored until the values for all phase shifters 48 are calculated, after which these values of the Phase shift can be delivered simultaneously via the lines 54 to the phase shifter 48. This temporary. Storage is done by three shift registers 276A to 276C, each of which is a number of cells or bit locations has equal to the number of phase shifters 48 wel-, before are included in the lens 40 according to FIG. Each of the shift registers Thus, in the preferred embodiment of the invention, 276a-C has 824 cells. In Figure 9 there are a few

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of these cells as an example and provided with the reference numbers 1, 2, ... 823 and 824. Those with the reference number 1 designated cells store the digits of the binary number, which is the phase shift command signal of a phase shifter 48, which is arbitrarily designated as phase shifter no. 1, those designated with 2 are stored in a corresponding manner Cells of the shift registers 276A to 276C the digits of the binary number, "suffice the phase shift for the phase shifter No. 2 represents. Oa each of the shift registers 276A-C stores only a single digit of the three-digit binary number which is on occurs on lines 266A-C, the digit stored by shift register 276A corresponds to a phase angle of 45 electrical degrees, while the digits stored by shift registers 276B and C correspond to phase angles of 90 electrical degrees and 180 electrical degrees, respectively.

Each of the shift registers 276A to 276C has parallel output lines for controlling multiplex selector holders 278, each of which has a multiplex selector stereo holder 27t for one each the total of 824 phase shifter exists and each multiplex selector holder 278 three inputs old with the designations A, B and C has bit 276C for receiving the respective digits of the binary numbers from the cells of the corresponding shift register 276A. The cells no. 1 of the shift registers 276A to 276C have old de » Multiplex selector holder 278 with the designation MUX No. 1 connection that cells # 2 of shift registers 276Λ to C have with the multiplex selector switch 278 with the more detailed designation MUX No, 2 connection and corresponding connections are to the Remaining multiplex selector mounts 278 made. The multiplex selector switches 278 are of a known type and each provide the digital equivalent of a single-pole switch Multiple selector contacts, in which the single output 280 of the multiplex selector switch 278 with one of the lines 282 can be connected and the respective connection to be established between a line 282 and the line 280 according to the binary

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reu number is selected that is connected to inputs A, B and C of the multi-tiplex selector switch 278 appears.

As' before regarding the creation of the correct magnetization of the ferrite material in each phase shifter of the lens 40 according to FIG Figure 1 was carried out, a voltage pulse of a predetermined duration of a winding surrounding the ferrite material so supplied that the magnetizing flux, which is proportional to the integral of the voltage of the pulse, has the value corresponding to the desired phase shift produce. The pulse duration required to introduce phase shifts of 45 °, 90 °, 135 ° ... 315 °, is experimental determined for the relevant ferrite material used in the phase shifter and for generating the voltage pulses, which occur on lines 282 and the required im- Have pulse width, a pulse generator 284 is provided. As As indicated in the drawing, the pulse width is one which appears on line 282 and produces a phase shift of 45 Impulse relatively narrow. A phase shift of 0 ° is not associated with any pulse on line 282. The momentum for a 90 phase shift is approximate twice as wide as the momentum for a 45 phase shift and the longest pulse duration acts for a 315 phase shift a. The use of a pulse generator 284 to provide a group of pulses on lines 282 with each any predetermined pulse width in cooperation with the multiplex selector switches 278 to select those pulses enables the compensation of non-linearities within the phase shifter 48, so that a very precise control of the phase shifter is possible. There are a total of eight lines 282 for generating any amount of phase shift in the above Way provided in soles of 45 what modulo 360 seen. The pulse generator 284 also provides a state control signal over the line 285, which is used for setting and resetting of the phase shifters is used in a manner to be explained in connection with FIGS. 10 and 11.

309815/1093

Each line 280 carrying a selected excitation signal is via an OR gate 286, on which nooh below is received, coupled to a line 287. Every Line 287 and the line carrying the state control signal 285 are combined in separate connection cables for the individual phase shifters, with each connection cable in the Figures 9 and 1 as the respective leading to a phase shifter Line 54 is designated.

FIG. 10 is a schematic circuit diagram of driver circuit 250 and the connections to coils 288 and 290 of the associated phase shifter 48 reproduced. The driver circuit 250 contains digital inverters 292, 294, 296 and 298, which convert a logical ONE into a logical ZERO and vice versa in a known manner, NANü switching elements 300 and 302 and a pair of emitter follower mounts 304 and 306, which respectively Transistors 308 and 310, diodes 312 and resistors 314 and 316 included. The emitter follower circuit 304 feeds the coil 290 for setting the phase shifter 48 to a specific Phase shift value and the emitter follower circuit 306 feeds the coil 288 for resetting the ferrite material of the phase shifter 48 to a known reference state of the magnetic flux. There is one driver circuit 250 for each of the 824 phase shifter 46 is provided, the driver circuits 250 being identical to those shown in FIG Own circuit structure.

In operation, driver circuit 250 takes digital pulse signals on lines 285 and 287, inverts these signals by means of inverters 292 and 294, after which the inverted signals get to the NAND gate 300. In addition, that is on signal appearing on line 285 along with the inverted form of the signal on line 287 to NAND gate member 302 fed. The at the outputs of the NAND Sohaltglieder 300 and 302 occurring signals are then again by means of the digital

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Tal inverters 296 and 298 inverted and the emitter follower circuits 304 and 506 / The latter two circuits essentially receive the waveforms of the signals appearing at the outputs of the digital inverters 296 and 298 and bring about a power amplification of these signals level suitable for operation of coils 288 and 290. the Coil 290 is connected in series with a resistor 3I8, the in the collector circuit of the transistors 508 and 310 between the KoI-lektoran connections and a voltage source 320 is * the resistance 318 and a capacitor 322 serve as filters for isolation of coils 288 and 290 from each other as well as for attenuation from interference from voltage source 320. In the same way, the coil 288 is in series with a resistor 318 la collector circuit of the emitter follower circuit 306 between the Collector connections of transistors 508 and 310 and the voltage source 320 laid. Resistors 314 and 316 are known in FIG Designed so that a suitable bias voltage for transistors 308 and 310 is generated. The diode 3i2 prevents dag too large negative overvoltages occur to a to ensure proper operation of the maintenance facility.

The signals appearing on lines 285 and 287 are shown in the time diagram according to FIG. In addition, in FIG. Ii those appearing on lines 282 and indicated in FIG Pulse waveforms are shown, three of these pulse waveforms being designated by the reference numerals 324, 326 and 328 in both drawings. The waveforms show a part of the clock-wise control signal on the line or on the line 287 according to FIG. lenform 32 * has a relatively short duration to get the correct Generate flux for a phase shift of 45 ° while the pulse waveforms 326 and 308 are wider and the have to produce the correct flux for phase shifts of 90 ° or 135 °. In Figure 11, the pulse waveforms 324, 326 and 328 shown as negative-going pulses with a voltage amplitude of, for example, 5 volts. After triple

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Inversion by means of the digital inverters 294 and 296 and the NAND gate 300, these pulses appear to be more positively directed Pulse at the base of transistor 308. That is valid in the preferred embodiment of the invention The time scale is indicated in Figure 11 and it can be seen that the clocked control signal on line 287 during the first 50 microseconds has a voltage of zero volts and then transitions to a value of 5 volts. The clocked control signal returns the value of zero volts for the duration of a flow generating Signal as shown by pulse waveform 324 is. It should be noted that the tail end of each pulse of waveforms 324, 326, and 328 is at 90.625 microseconds occurs, but the forehead of the respective pulses occurs at different times depending on the pulse width. Since the Phase shifter 48 own self-holding property will be them no further flow-generating drive signals are supplied until the beam 56 of Figure 1 is set to a new direction shall be.

The switching state control signal of line 285 is also shown in FIG. It lasts for 55 microseconds has a value of 5 volts and has a value of zero volts for the rest of the working cycle. During the first Microseconds during which the clocked control signal a has a low voltage of zero volts and the switching state control signal has the high voltage of 5 volts, no signal appears at the output of the emitter follower circuit 304, however a reset signal occurs at the output of the emitter follower control 306 on. This can be easily done by following the logic circuit path through inverters 292, 294, 296 and 298 as well as through the NAND switching elements 300 and 302. After a time of 55 microseconds, after which the voltage of the switching state control signal drops to zero, the remains The output of the NAND gate 302 is at its high value, so that no reset signal is present at the output of the emitter follow-up circuit 306 can occur. Since the inverted, the switching

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was the controlling voltage signal, which is transmitted via the inverter 292 reaches the NAND holding element 300 ", now has a high voltage value, the NAND holding element 300 is excited and leaves that inverted control signal from inverter '294 duroh when this signal is high. This high value in turn will reached during the duration of pulse waveforms 324, 326 and 328, at what time the emitter sequencer 304 actuates is to magnetize the ferrite material of the phase shifter 48 in the sense of generating the desired phase shift. It should therefore be noted that this is what controls the switching state Signal on line 285 the times of setting and resetting the phase shifter 48 controls, while the cyclic control signal of the line 287 determines the flow rate, which is required to generate a certain phase shift.

When constructing the antenna 32 according to FIG. 1, the lens 40 and the horn antenna 42 are expediently arranged in a housing construction not shown in the drawing, which has the shape of a miniature radome and which is transparent to the radiation emitted by the antenna 32 and the lens 40 and the horn radiator 42 from the effects of the weather. Due to this wrapping or encapsulation and due to the structure of the lens 40 itself, this undergoes a temperature increase, welohe by ^1, the heat loss due to the radiation passage duroh the phase shifter 48 as well as due to the electric currents in the driver circuits 250 shown in FIG 10 is verursaoht. It is known that the electrical properties of ferrite material, as used in the phase shifters 48, change with temperature, which means that compensation for the thermally induced changes in the electrical properties is to be carried out when an antenna 32 is to be made that one to enable precise beam control. The heating and its compensation will be dealt with below with reference to FIGS. 9 and 12.

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FIG. 12 also shows a front view of a lens 40 according to FIG Figure 1 shown, wherein the various phase shifters 48 are arranged in vertical rows, which against each other slightly are offset to the lattice-like formation of maxima and Reduce minima. The vertical rows of phase shifters extend in the central part of the phase shifter arrangement from the bottom of the lens 40 to the top of the lens while the rows of the phase shifter arrangement closer to the sides are kept somewhat shorter. Lens 40 is shown according to Figure 12 divided into temperature zones, the lower Near the edge of the zone experiences a temperature increase compared to the surroundings of 6.5 ° to 6 °, the lower central zone a temperature increase from 6 to 8, the upper central zone has a temperature rise of 8 ° to 10 ° and the upper zone Sohließlioh experiences a temperature increase of 10 to 12.

With reference to FIGS. 9 and 12 it is now shown that the compensation the thermally induced changes in the electrical properties of the phase shifters 48 duroh amplification of the the flux generating drive signals for the ferrite material is carried out. Accordingly, additional drive signals for the phase shifters are supplied from the pulse generator 284 over the lines 230 and these compensation drive signals are in the form of Reohteo pulses, the pulse width of the value zero (no temperature compensation) for the phase shifters 48 in the warmest zone according to FIG. 12 up to a value of about 1.1 microseconds for the phase shifters 48 in the coolest zone of FIG. As also from Figure 12 As can be seen, the compensation drive signals arrive on lines 230 at pulse widths of approximately 0.3 microseconds and 0.6 Microseconds to phase shifters 48 in the upper temperature middle zone or the lower middle temperature zone. The compensation drive signals are fed from lines 230 to those shown in FIG 10 shown driver circuits 250 via lines 232 and the OR gate 286 according to Figure 9 and from there via the Lines 287 coupled. The driver circuits 250 speak

309815/1093

sr

aul the compensation driver signals which are transmitted over the lines
287 are supplied, in the same way as was previously carried out with regard to the clock-wise control signals also supplied via the lines 287. As shown in the timing diagram of Figure 11, the compensation drive signals,
which are designated in the diagram with "TEMP COMP", expediently immediately after the end of the pulse 324, 326 or
328 of the control signal.

Finally, FIG. 13 shows a timing diagram or schedule
of the system shown in Figure 1. The timing diagram
consists of successive, alternating intervals with the designations A and B, the former having a duration of 90 microseconds and the latter interval a variable duration from 660 microseconds to 1000
Has microseconds. During the interval A, the delivers
Reohner 86 the angle information for aligning the beam 56 and the beam control unit 88 sets the phase shifts on the phase shifter 48 so that the
results in the desired beam direction. During the interval B, the system 30 establishes communication with the aircraft 34 by transmitting and receiving radiant energy between the antenna 32 and the aircraft 34. This connection with the aircraft 34 can be improved by using a transponder or a repeater beacon 234, which is arranged in the aircraft 34 according to FIG. 1 and is used to identify the aircraft and to provide additional data such as the flight altitude. During the interval B, the computer 86 determines
based on the movement data of the aircraft 34 received from the antenna 32 as well as from the airspace surveillance radar 120 and from the
Data entered at the control panel 92 are derived, the next direction of the beam 96.

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Claims (25)

Claims Ij device for focusing wave energy, especially for antennas, characterized by the fact that the phase position of individual radiation beams is independent of one another
phase shifter arrangement (40 or 140 or 148) that changes from one another and thereby changes the direction of a resulting wavefront and by one at a distance from this and in the passage
the deflection device (38 or 144 or 154) located on the beams hitting the phase shifter arrangement, which changes the direction of individual radiation beams impinging on them in relation to one another in accordance with the respectively impressed phase position so that essentially independently of the direction of a beam assigned to the deflection device ( 56) of that
Directional characteristic remains the same. 2. Device according to claim 1, characterized in that the deflection device is in the form of a wave energy on the relevant acting lens (144) (Figure 2), 3. Device according to claim 2, characterized in that the lens (144) elements or areas are each different
Has deceleration behavior with respect to the wave energy impinging on it (Figure 2). 4. Device according to claim 1, characterized in that the deflecting device has the shape of a reflector (38) whose
Surface is formed by rotating a conic curve. 5. Device according to claim 4, characterized in that the axis of rotation of the conic section curve with the axis of the relevant Conic section coincides. - 36 - 309 815/1093 6. Device according to claim 4 or 5, characterized in that that the reflector surface is a surface area of a hyperboloid of revolution is. 7. Device according to one of claims 4 to 6, characterized in that that the reflector (38) is shaped so that the effective Radiation opening (46) reflected on the reflector and impinging on or proceeding from the phase shifter arrangement Beam (56) remains the same regardless of the direction of the beam. 8. Device according to one of claims 1 to 7, characterized in that that the phase shifter arrangement of one on its reflector surface in certain areas with each adjustable Phase shift reflective reflector (148) formed is (Figure 3). 9. Device according to one of claims 1 to 7, characterized daduroh, that the phase shifter arrangement is effective as a lens (40 or 140) with respect to the wave energy to be focused, which has a curved surface in at least one direction having. 10. Device according to claim 9 _; characterized in that the surface of the phase shifter arrangement (40 or 140) is cylindrically curved. 11. Device according to one of claims 1 to 10, characterized in that that the phase shifter arrangement (40 or 140 or, 148) consists of individual phase shifter elements (48 or 142 or 150) is composed, at welohen by means of phase shift control signals In each case certain phase shifts are electronically adjustable (5 ^) and that on a beam control command signal (112> appealing soaking agents (86, 88, 250) are provided for generating the phase shift control signals. - 37 - 309815/1093 12. The device according to claim 11, characterized in that said circuit means have a computing device (86) for Calculation of the phase shift values included at each the phase shifter elements (48) for aligning the radiation beams must be made in accordance with the direction given by the beam control command signal. 13. Device according to claim 12, characterized in that the holding means (86, 88, 250) a signal generator (284) to provide a group of pulses included, each are able to generate a predetermined phase shift in these when fed to the phase shifter elements (48) and that switching means responsive to the phase shift values calculated by the computing device (86, 264, 268) (276A to 276c, 278) are provided in order to couple certain of said pulses to certain of said phase shifter elements (Figure 9). 14. Device according to one of claims 11 to 13 »characterized in that that in said circuit means additional pulses (230, 232, 280) for temperature compensation to the Phase shifter elements (48) can be generated (Figures 9 and 12). 15. Device according to one of "Claims i to 14, characterized in that that the phase shifter arrangement (40 or 140 or 146) can be controlled in such a way that radiation beams impinging on it leave the phase shifter arrangement diverging in the direction of the deflection device (3β or 144 or, 154), which one surface generated by a conic curve has such a shape that such a reduction in radiation divergence takes place that the radiation beams are essentially bundled and the beam formed (56) is effective Has radiation opening which is larger than the effective area of the phase shifter arrangement. / - 38 - 309815/1093 16. Device according to one of claims 1 to 15, characterized in that that by means of the deflection device (38) one of one Radiation source (34, 234) outgoing beam (56) can be directed towards the phase-separator arrangement (40) and that with the Ahlenkeinrichtung and the phase shifter arrangement an evaluation device (42, 76, 78) is coupled, by means of which information relating to the radiation source is obtained from the beam are derivable. 17. Device according to claim 16, characterized in that the data which can be derived by means of the evaluation device (42, 76, 78) are movement data of the radiation source (34, 234), 18. Device according to claim 16 or 17, characterized in that that by means of a beam control unit (88) on the phase shifter arrangement (40) an independent change in the effective phase shift in each area or element by element is adjustable. 19. Device according to claim 17 and claim 18, characterized in that that the beam control unit (88) is coupled (82, 112, 86) to the evaluation device (42, 76, 78) in such a way, that the phase adjustment takes place in the sense of the generation of a received beam, which a future position of the radiation source (34, 234) meets. 20. Device according to one of claims 16 to 19, 'characterized * that the deflector (38) and the phase shifter assembly (40) sending means (42, 80, 84) for sending out of radiation in the direction of the radiation source (34, 234) are assigned. 21. Device according to claim 20, characterized in that the transmitting means (42, 84, 80) in such a way with the Aüswerteinrichtung (42, 76v ~ 78) are coupled that a Correlation of the received signals with the transmitted signals can be carried out is. ■ ■■ - 39 - 3098 15/1093 22. Device according to one of claims 16 to 21, characterized in that that the radiation source comes from a relay element or a repeater beacon (23 * 0 is formed. 23 * Device according to claim 22, characterized in that from the radiation energy received from the radiation source or the vehicle and from the current position the radiation source or the vehicle in accordance with the instantaneous values of the respective effective on the phase shifter arrangement Phase shifts a future position of the radiation source or the vehicle can be calculated (86), 2k. Device according to one of Claims 1 to 23, characterized in that the deflection device (3B) is arranged in the near field of the phase shifter arrangement (hO) . 25. Device according to one of claims 1 to 2k, characterized in that at least the deflection device is arranged on the path (36) of an object or vehicle (3 * 0) to be detected with a beam to be focused (56). 30981 5/1093 Blank page