Three-port polarization and frequency-duplexing device

DESCRIPTION

The present invention relates to a three-way polarization and frequency duplexer device.

In polarizing duplexer material, the orthomode type duplexer is known which comprises a main guide, on whose axis a short-circuit blade is placed, and another guide, called a parallel access guide, orthogonal to the first and placed in a crotic position with Regarding this short circuit blade. This very classic device has the disadvantage of being limited to the use of a single frequency or frequency band.

On the other hand, a duplexing device is known, as described in the patent application EP-A1 0 192,186 filed on February 15, 1985, subsequently published on the priority date of the present application and comprising a main guide that transports both the frequency or frequency band of the multiplexer and other frequency bands of two orthogonal access guides to the main and orthogonal guides between them that are coupled to the main guide by resonance slots.

This mode of realization is not compatible with the requirements of multi-source implantation.

European patent application EP-A-0098192 describes a multiplexing device for grouping two frequency bands. This device for a multiband antenna comprises in series from the coupling access to the antenna: a circular common guide, which allows the passage of a band of high frequencies and a band of low frequencies, into which they flow through of two coupling holes displaced with respect to each other along the circular common guide, two orthogonal guides between them, which constitute the accesses for the two orthogonal polarizations of the low band; a transition guóa round-guóa-round; a polarization duplexer for the high band. In the coupling holes these are resonator arrangements that form a short circuit for the high band frequencies. In the circular common guide, a first quasi-optic filter, whose role is to reflect towards the first coupling hole, the waves located in the first and second coupling hole was arranged, seen from the coupling access to the antenna. low band and whose polarization is that of the wave destined to pass through the first hole, and between the second coupling hole and the transition was arranged a second quasi-optical filter whose role is to reflect towards the second coupling hole the waves located in the low band and whose polarization is that of the wave destined to pass through the second hole .

With regard to this device of the known technique, the invention has as its object a realization device and they executed much simpler with two low frequency accesses and a high frequency access and not the other way around.

The present invention relates to a device that allows two orthogonal polarization planes to be extracted or excited at a low frequency in the fundamental way and to extract or excite a polarization plane in a fundamental frequency to coplanar to one of the polarization planes of the Low frequency.

The present invention aims at a duplexer polarization and three-access frequency device, comprising, on the one hand, in series with respect to a coupling access to an antenna: a circular common guide, comprising the passage of two orthogonal polarizations of a wave in a low frequency band and a polarization of a wave in a high frequency band parallel to one of the two orthogonal polarizations of the low frequency wave, a transition, a secondary guide, and, on the other hand, a first access guide for one of the two orthogonal polarizations of the wave in the low frequency range that flows, through a resonance groove, in the common guide, a second access guide to the secondary guide, orthogonal to this, and which was coupled through a resonance groove, a short-circuit blade, which forms a short circuit with the part of the high frequency wave, intended for this second access guide, the free end of the secondary guide forming a third access guide or serial access guide, characterized in that the secondary guide is a rectangular guide, whose narrow side is parallel to the second polarization of the low frequency wave, and whose wide side is parallel to the polarization of the high frequency wave, because the first access guide to the common guide comprises a filter intended to select the wave in the low frequency band generating at the level of the resonance slot a short circuit for the high frequency wave, and because the second access guide is orthogonal to the wide side of the secondary guide and constitutes the access for high frequency wave polarization.

The present invention has the great advantage of presenting two exits located in the same plane and which, therefore, are easily accessible, which is very important in the space field.

On the other hand, the features and advantages of the invention were deduced from the description that follows, by way of non-limiting example, with reference to the attached Uonic figure representing a partially exploded perspective view of the device of the invention.

The device according to the invention is an excitation device of a low frequency F1, and an extraction or excitation device of a component of the fundamental mode corresponding to a high frequency F2.

This device comprises a main guide 1 corresponding to the fundamental mode of the frequency F1, an access guide 4 corresponding to the frequency F1 orthogonal to the main guide 1, a transition 5 between the main huoa 1 and a rectangular guide 7, whose wide side corresponds to the fundamental mode of the frequency F1, and the narrow side corresponds to the fundamental mode of the frequency F2, and an access guide 8 corresponding to the orthogonal frequency F2 to the wide side of the rectangular guide 7. The rectangular guide 7 comprises a short-cut blade 10 parallel to its wide side. Orthogonal access 4 to the main guide 1 and orthogonal access 8 to the guide

018 791 rectangular 7 are coplanar. The access guide 4 orthogonal to the main guide 1 is coupled thereto through a resonance slot 2. The access guide 4 comprises a filter 3 intended to select the frequency F1, the filter 3 being constructed to substantially reset on the resonance slot 2 a short circuit for frequencies outside the F1 frequency. The access guide 8 orthogonal to the rectangular guide 7 was coupled to the rectangular guide 7 by means of a resonance groove 9 and placed in a certain position with respect to the short-circuit blade 10.

The operation of the device just described is as follows:

Coming from the receiving antenna, to which it was connected, for example, the device of the invention, orthogonal polarization waves arrive on the one hand at a first frequency F1, for example 12 GHz, and on the other hand, a wave of a second frequency F2, for example 18 GHz, of polarization parallel to one of the polarization planes at the frequency F1. The F1 frequency waves propagate in the main guide 1 following their fundamental mode and following two orthogonal polarizations.

The first polarization of the first frequency F1 was located in the plane of the figure and the second polarization is orthogonal to this plane.

At the moment when the component parallel to the plane of the groove 2 reaches the level of this coupling groove, a first part thereof is derived by the groove groove 2 towards the filter 3 and, therefore, towards the access guide Four.

The part of this component that is not directed towards the guide 4 continued to propagate in the guide 1, then in the first part of the transition 5 in which it is reflected to the right of the short circuit plane 6 to return to the coupling groove 2 which then directs it to guide 4, as explained above. A part of the wave, on the other hand negligible in the practice, which is not directed at this time towards the guide 4, is then reflected towards the radiating element.

Of course, in a manner known to the technician, the distance between the short circuit plane and the radiating slot 2 is adjusted so that a maximum of reflected waves is absorbed by the guide 4.

The second frequency component F2 propagates in the main guide 1 without being derived by the coupler 2, which is presented, on the other hand, against this frequency as a short circuit, then in the transition 5 to continue its path in the guide rectangular 7. In part it is directed towards the guide 8 through the resonance groove 9 sized to resonate at this frequency F2.

The part of this component that is not directed towards the guide 8 continued to propagate in the guide 7, in which it is reflected on the short-circuit blade 10 to return to the resonance groove 9.

A part of the wave, on the other hand negligible in practice, which is not directed at this time towards the guide 8 is then reflected towards the radiating element.

Of course, the distance between the short-circuit blade 10 and the radiating slot 9 is adjusted, in a manner known to the technician, so that a maximum of reflected waves is absorbed by the access guide 8.

The second component of the frequency F1 orthogonal to the plane of the slot 2 is propagated in the main guide in the transition 5 and in the guide 7 without being derived neither by the coupler 2, nor by the coupler 9, nor by the short-circuit blade 10 , and goes to access 11, called "serial access".

The device just described is susceptible to a large number of interesting applications. For example, it is possible to use this device in a primary source of multi-source antenna. This antenna operates following three accesses: for example, with two reception accesses, a broadcast access, and reciprocally; or with a broadcast access, a reception access and a telemetry access.

An absorber element can be placed in the access guide 11. In any linear polarization, the received component, orthogonal to the extracted component, will be absorbed by the absorber element on the two frequency bands and thus will not disturb the operation of the source.

Of course, the present invention has only been described and represented by way of preferred example and that its constituent elements may be replaced by equivalent elements without, therefore, departing from the scope of the invention.

When talking about F1 and F2 frequencies, it is, of course, two low and high frequency bands.

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