WO2010106198A1

WO2010106198A1 - Polarisation rotator with multiple bowtie-shaped sections

Info

Publication number: WO2010106198A1
Application number: PCT/ES2009/070069
Authority: WO
Inventors: Jorge Alfonso Ruiz Cruz; Jose Ramón MONTEJO GARAI; Jesús María REBOLLAR MACHAIN
Original assignee: Radiacion Y Microondas, S.A.
Priority date: 2009-03-18
Filing date: 2009-03-18
Publication date: 2010-09-23

Abstract

Polarisation rotator by β° between an input waveguide (6) and an output waveguide (7) formed by interposing between the input and output waveguides (6, 7) at least two parallelepiped sections in which a bowtie-shaped cut-out (24, 26) has been made which has two axes of symmetry, one along a longitudinal axis and another along a transverse axis, and which is defined by a series of constructive parameters and has its longitudinal axis at an angle to the axis of one of the input and output waveguides, wherein the sections are identical constructively by pairs, one section being identical to the section placed symmetrically to it about a central point and being at an angle θ. to the axis of the nearest waveguide and, if the number of sections is odd, being inclined β°/2 to either of the two waveguide axes; this construction providing an adaptation better than 40 dB, compactness, minimum length, ease of machining and sturdiness.

Description

POLARIZATION TURNER WITH MULTIPLE SECTIONS IN FORM

OF BABY

DESCRIPTION OBJECT OF THE INVENTION

The object of the invention is an electromagnetic wave polarization spinner that has a multiplicity of sections that each have a bow-tie shape, the bow-shaped section of each section being rotated relative to the adjacent one.

The present invention characterizes the special configuration and design of the section in the form of a bow tie that each of the bow ties presents, as well as the angle of rotation that each section presents in order to achieve a polarization spinner that has a maximum compactness , a minimum length and an adaptation of the electromagnetic wave better than what has been achieved so far.

Therefore, the present invention is within the scope of polarization rotators for waveguides.

BACKGROUND OF THE INVENTION

There are numerous attempts to get electromagnetic wave polarization spinners.

Some, like those marketed by the FLANN company, are spinners that are manufactured from waveguides that have been rotated precisely while maintaining the dimensions of the waveguide. This way of achieving polarization rotators has several disadvantages, on the one hand, inconveniences derived from the manufacturing process itself, since it must be subjected to the waveguide at high temperatures to be able to be twisted, this causes stress in the material which forces to analyze the material again, on the other hand a reduction of the dimensions of the spinner is not achieved.

A torsion turn analysis of a waveguide is performed in the article "An Analysis of a Hybrid-Mode in a Twisted Rectangular Waveguide" (Hatsuo Yabe, Yasuto Mushiake) published in IEEE Transactions on Microwave Theory and Techniques, VoI MTT-32, no 1, January 1984.

Another known solution to achieve the polarization turn in order to avoid the previous drawbacks is described in the following article: "Design of Compact Waveguide Twists" by (Pedro I. Alonso-Juaris-ti, Jaime Esteban and Jesús Maria Rebollar published in IEEE Transactions on Microwave Theory and Techniques, VoI 45, no 5, May 1997. In this article the polarization spinner is based on an alternate succession of rectangular and circular section waveguides, where rectangular section waveguides are arranged successively turned in order to achieve the total turn, although some of the problems stated in the first proposed solution are avoided, it does not solve the problem of compactness, and besides, the manufacturing process is not favorable.

In the article "FuIl Wave Design of Broad-Band Compact Waveguide Step-Twists" (Massimo Baralis, Ricardo Tascone, Oscar Antonio Peverini, Giusseppe virone, Renato Orta) published in IEEE Microwave and Wireless Components Letters, VoI 15, no 2, February 2005, describes a polarization spinner formed by a succession of sections or elements that have a section rectangular, providing a section in relation to the consecutive turned. Although a certain compactness is achieved, a better adaptation of 40 dB is not achieved in the entire useful band of the guide.

Another solution known in the state of the art is that described in the US patent 6879221 Bl, in which a polarization spinner is described which provides an orthogonal rotation where both waveguides are arranged orthogonally with respect to a coupling transformer. in this one through a smaller section. This proposed solution, in addition to not being compact, is only valid for orthogonal rotation rotations, and the adaptation performance achieved has a very small bandwidth compared to the present invention.

The article entitled "Polarization Rotator- Analysis and Design" (Rafal Lech, Jerzy Mazur, published in the 14th Conference on Microwave Techniques, COMMITTEE 2008, April 2008) describes a new analysis of a polarizer composed of sections of frequency selective surfaces . The analysis is conducted considering the polarizer as a cascade connection of several elementary layers that is composed of periodic linear matrices of metallic wires.

Finally, the article "Compact 90 ° Twist formed by a Double-Corner-cut Square Waveguide Section" (Anato-üy, Kirilenko, Dimitriy Y. Kulik, and Leonid A. Rud) can- Listed in IEEE Transactions on Microwave Theory and Techniques, VoI 56, not JuIy 2008, it shows a rectangular waveguide spinner where the section in charge of the rotation is formed by a square section that presents two cuts in two of its square corners. Although a certain compactness is achieved, only a 90 ° rotation is achieved, and a better adaptation than that achieved so far is not achieved.

Therefore, exposed the different polarization rotators known so far it is the object of the present invention to develop a polarization rotator according to the characteristics of the first claim, which allows an adaptation improvement of 40 dB in the entire useful band of the guide, which has a maximum compactness and minimum length in the longitudinal direction, with a reduced mass and volume and very easy to manufacture.

DESCRIPTION OF THE INVENTION

The object of the invention of the polarization spinner, as already stated, is a spinner that allows a better adaptation of 40 dB in the entire useful band of the guide, which has a maximum compactness and minimum length in the longitudinal direction.

In addition to the stated objectives, the spinner is intended to be compact in the transverse direction, not exceeding conventional "flanges", which is also easy to machine and robust, that can be easily integrated into complex subsystems such as Orthodontics, EH mixed elbows and routing structures, which allow a cheap manufacturing with a very high repeatability, presenting little mass and volume, which present flexibility in the choice of the number of sections to comply with the specifications of either good adaptation of bandwidth, where also the degree of rotation can be greater or less than 90 ° as desired and where the spinner is not exclusively limited to sections of rectangular waveguides equal to the input and output, the waveguide section of the input and output may be different.

To achieve these purposes, a polarization spinner with multiple sections is proposed, each section presenting a bow-shaped emptying.

Each emptying in the form of a bow tie made in each section has two planes of symmetry, one along a longitudinal axis that runs along the largest dimension of the bow tie, and another plane of transverse symmetry that runs along a axis transverse to the previous one. Each emptying in the form of a bow tie is defined by a series of parameters that allow the precise construction of said emptyings.

The spinner can be formed by a variable number of sections, all of them with a bow-shaped hollow that have the same geometric shape, that is, they have the same constructive parameters.

The longitudinal axis of each of the bow-shaped hollows in each section has an angle relative to the axis of the input and output waveguides.

So in the case of wanting to form a 90 ° swivel with two sections with two emptying in the form of Bow tie, both recesses have the same construction characteristics and the longitudinal axis of each recess has an angle θ. in relation to the axis of the entry guide and the exit guide respectively, axes that logically are transverse when looking for a 90 ° rotator .

In the case that there were three sections used to form a 90 ° swivel, the two bow-shaped hollows of the extreme sections have the same parameters, and their longitudinal axes will have an angle θ. In relation to the axis of the input and output waveguides, while the bow-shaped emptying of the central section, will have its own constructive parameters and will present an angle of 45 ° in relation to any of the axes of the input waveguides or output to be a 90 ° spinner.

Thus, in order to standardize the parameters that must be taken into account for the design of a 90 ° swivel consisting of N sections, the constructive equalities and rotation of the bow ties are as described below:

The spinner has an even number of sections with bow ties.

For i = 1,2, ..., N / 2 And all bow-shaped voids have their longitudinal axis with an angle B ₁ in relation to one of the axes of the input and output waveguides.

Therefore the number of parameters necessary to define a spinner consisting of N sections, where N is an even number is 7 * N / 2. • the spinner has an odd number of sections with bow ties

.The ₁ ^~ LS (N- _I + I)

For i = 1,2, ..., (N-I) / 2

And all bow-shaped voids have their longitudinal axis with an angle B ₁ in relation to one of the axes of the input and output waveguides.

Now the bow-shaped emptying of the section (N + l) / 2 has the following parameters.

Rfl (ϊ + i) / 2

Rb (N + l) / 2

The (N + i) / 2

Lb (N + l) / 2 LC (N + l) / 2 E _{(N +} i) / ₂ And it is rotated 45 ° in relation to any of the axes of the input and output guides since a 90 ° rotation is sought.

Therefore the number of parameters needed to define a spinner consisting of N sections, where N is an odd number is 7 * [(N + l) / 2] -1

Thanks to the consecutive arrangement of several sections with bow-shaped hollows, not only 90 ° rotators can be achieved, but of any type of angle D between the entrance and the exit.

In the event that the spinner is made up of two sections with bow-shaped hollows, both hollows have the same construction parameters Ra, Rb, La, Lb, Lc, E and an angle D. is rotated relative to the axes of the waveguides of the input and output respectively.

In the event that the spinner has three sections with bow-shaped hollows, the parameters of the bow-shaped hollows of the extreme sections have the same construction parameters, Ra, Rb, La, Lb, Lc, E , each of which is rotated by an angle θ in relation to the axes of the input and output guides respectively, while the emptying of the central section has its own parameters and half of the rotation that is sought to be achieved is rotated or β / 2 in relation to any of the axes of the input and output waveguides.

Generalization for β ° spinners made up of N sections, depending on whether N is even or odd it is exactly the same as the one done previously only with the difference that instead of talking about angles B ₁ and 45 ° for the central section in case N is odd, we will talk about angles β _x and additionally of β / 2 for the central section in case N is odd.

EXPLANATION OF THE FIGURES

To complement the description that is going to be carried out below and in order to help a better understanding of its characteristics, this descriptive report is accompanied by a set of drawings in whose figures, in an illustrative and non-limiting manner, the most significant details of the invention.

Figures 1, 2 and 3 represent a 90 ° swivel formed by a single section, where Figure 1 is a perspective representation, while Figure 2 is a front view, and Figure 3 is a representation of the relationship of the emptying in the form of a bow tie in relation to the waveguides.

Figures 4 and 5 show a perspective view and a plan view with a section that has a bow-shaped hollow.

Figures 6, 7 and 8 represent a 90 ° swivel formed by two sections, where Figure 6 is a perspective representation, while Figure 7 is a side view, and Figure 8 is a representation of the relationship of the bow-shaped emptying in relation to the waveguides.

Figures 9 and 10 represent a perspective view of the two grouped sections and a view in plant where it is detailed how one of the empties is in the form of a bow tie in relation to the other.

Figures 11, 12 and 13 show a 90 ° swivel consisting of three sections that have two empty bow-shaped ones.

Figure 14 shows a representation in plan of the three sections where it is appreciated how an emptying is arranged in relation to another.

Figures 15, 16 and 17 show a β ° spinner with two sections with two empty ones in the form of a straw.

Figure 18 shows in detail the angle presented by the longitudinal axes of the bow-shaped hollows in relation to the axes of the input and output waveguides, in the case of a β ° spinner with two sections.

Figures 19, 20 and 21 show a D ° spinner consisting of three sections that have their respective bow-shaped emptyings

Figure 22 shows the angle presented by the longitudinal axes of the bow-shaped hollows in relation to the axes of the input and output waveguides in the case of a β ° rotator with three sections.

Figures 23 and 24 show a perspective and plan view of a section of those used in the polarization spinner where a series of perforations for alignment and fixation are observed. Figures 25 and 26 show a perspective and plan view of a set of two grouped sections.

PREFERRED EMBODIMENT OF THE INVENTION

In view of the figures, a preferred embodiment of the proposed invention is described below.

The invention of a polarization spinner with several bow-shaped sections, as already stated, consists of the adjacent arrangement of at least two parallelepiped sections of a certain thickness on which there are castings according to construction parameters, and presenting the longitudinal axis of each of the bow-shaped hollows a certain angle of inclination in relation to the axes of the input and output waveguides.

Thus, in figure 4, the constructive form of a section (1) can be observed, which, as already said, has a parallelepiped configuration with a bow-shaped hole (2).

Said emptying (2) has two axes of symmetry, one in relation to a plane that passes through a longitudinal axis (4) according to the largest dimension of said emptying, and another plane of symmetry that passes through a transverse axis (5) to the previous one . The emptying (2) assimilated to a bow tie form, is a form of approximation and has no limitation character, being simply a form of identification of the form to which it resembles. Said emptying (2) could be defined in terms of two rhombuses or lobes aligned by one of its vertices or ends and arranged said vertices or ends superimposed.

In figure 5 you can see the parameters that are used for the construction of the hollows (2), with the following parameters, Ra, Rb, La, Lb, Lc and the thickness E.

The constructive parameters are not limiting, being able to use other constructive parameters, the really relevant aspect of the invention is the approximate general form in the form of a bow tie that presents the emptying and that has two axes of symmetry and that by means of tests has allowed to achieve an adaptation spinner better than 40 dB, with maximum compactness and minimum length.

Thus, in figures 1 to 3, a 90 ° swivel has been represented formed by a single section, the contour (3) of the recess (2) having been represented, since for electromagnetic effects the essentially relevant is the shape of the contour (3) emptying (2).

Although the embodiment with a single section that presents a bow-shaped emptying could be a possible constructive form, it is not possible to have an adaptation better than 40 dB, so it is necessary to use at least two sections arranged adjacently.

Thus, in Figures 6, 7 and 8 it is shown what a 90 ° rotator would be made up of two sections, the contours (3a) and (3b) of each of the emptyings made in each of the sections having been represented, for better viewing and compression of produced effect

In figure 9, it is observed how the two sections (1) are arranged adjacently by their major face, each of them presenting their respective hollows (2a) and (2b) which have a butterfly shape.

Figure 10 shows how the longitudinal axis (4a) of the recess (2a) has an angle D relative to the axis (6.1) of the input waveguide (6), while the recess (2b), its longitudinal axis (4b) has an angle D relative to the axis (7.1) of the output waveguide (7).

In figures 11 to 13, it is possible to observe the construction of a 90 ° rotator formed by three sections, which have not been represented, having represented only the contours (3a), (3b) and (3c) of each of the emptyings Performed in each of the sections, each one of said empties will present constructive parameters and an inclination in relation to the axis of the entry and exit guides.

Thus, in figure 14 it is observed that the emptying (2a) its longitudinal axis (4a) has an angle D in relation to the axis (6.1) of the inlet guide, while the emptying (2c) also its longitudinal axis (4c) ) has an angle θ in relation to the axis (7.1) of the exit guide this time, while the emptying (2b) of the intermediate section has an angle of 45 ° in relation to any of the axes of the entry guides and output (6) or (7) since they are perpendicular to each other.

Therefore, for a spinner made up of three sections, the construction parameters required Riamos would be: those corresponding to the emptyings (2a) and (2c) of the extreme sections that would be the same parameters, that is:

E ₁ = E ₃

Where both emptied (2a) and (2c) are turned an angle θ in relation to the respective axis of the waveguide to which they are attached. and the parameters corresponding to the emptying (2b) of the intermediate section, that is: Ra ₂ , Rb ₂ , La ₂ , Lb ₂ , Lc ₂ , E ₂ forming an angle of 45 ° in relation to any of the axes of the waveguides of input and output.

In case you want to generalize what a 90 ° rotator with a number of sections would be constructively, analyzing how the constructional characteristics of the bow-shaped hollows of the sections would be, and the total number of parameters needed to its designs, we would distinguish between each other the number of sections is even or odd: • 90 ° swivel with an even N number of sections with bow-shaped hollows.

₁ ⁼ La (N-iti)

For i = 1,2, ..., N / 2

And all bow-shaped hollows have their longitudinal axis with an angle B ₁ in relation to one of the axes of the input and output waveguides.

Therefore the number of parameters necessary to define a spinner consisting of N sections, where N is an even number is 7 * N / 2.

90 ° swivel with an odd number of sections with bow-shaped emptyings

Ra ₁ = Rd ( _B - _{I +!} )

For i = 1,2, ..., (N-I) / 2

Lb (NtI) / 2 LC (N + l) / 2 E (N + l) / 2

And it is rotated 45 ° in relation to any of the axes of the input and output guides since a 90 ° rotation is sought.

In Figures 15, 16 and 17, a β ° swivel is formed, consisting of two sections interposed between the input guide (6) and the output guide (7), that is, the axes (6.1) and (7.1) of the guides of input (6) and output (7) waves have an angle of β of each other. The contours (3a) and (3b) of the corresponding recesses of the sections have been represented in the three figures.

In Figure 18, it is observed how the contours (3a), and (3b) would be arranged in relation to the input waveguides (6) and (7) respectively. Thus we can observe that a first contour (3a) whose longitudinal axis (4a) has an angle θ in relation to the axis (6.1) of the guide (6), while the contour (3b) its longitudinal axis (4b) has an angle θ in relation to the axis (7.1) of the waveguide (7), presenting between both axes (6.1) and (7.1) an angle of β °. The constructive parameters of the recesses are the same, that is, only Ra, Rb, La, Lb, Lc and E, and the angle θ should be defined.

Figures 19, 20 and 21 show the constructive form of a β ° swivel formed by three sections that have straw-shaped emptyings. rita, having represented only the contours (3a), (3b) and (3c) of the corresponding emptyings, observing the disposition they adopt in relation to the input and output waveguides.

In figure 22, we can see how these contours would be arranged. Thus we find that the contour (3a), its longitudinal axis (4a) has an angle D in relation to the axis (6.1) of the entrance guide (6), while the contour (3c) corresponding to the other end section attached to The waveguide (7) also has its longitudinal axis (4c) an angle D in relation to the axis (7.1) of the output guide (7), finally the contour (3b) of the emptying of the intermediate section has an angle D / 2 in relation to any of the two axes (6.1), (7.1) of the input and output waveguides.

Thus, in the case of a β ° spinner consisting of three sections, the parameters necessary to define it are:

Rb ₁ = Rb ₃ La _x = La ₃ Lb ₁ = Lb ₃

E ₁ = E ₃

Where both hollows are turned an angle θ in relation to the respective axis of the waveguide to which they are attached. and the parameters corresponding to the emptying (2b) of the intermediate section, that is: Ra ₂ , Rb ₂ , La ₂ , Lb ₂ , Lc ₂ , E ₂ forming an angle of β / 2 in relation to any want of the axes of the input and output waveguides.

The generalization for D ° rotators conformed by N sections, depending on whether N is even or odd, is exactly the same as that done previously only with the difference that instead of speaking of angles B ₁ and 45 ° for the central section in case that N is odd, we will speak of angles B ₁ and additionally of β / 2 for the central section in case N is odd.

Figures 23 to 26 show that the sections (1), in addition to the bow ties (2) in the form of a bow tie have a series of perforations, where the four oblong perforations (8) of the vertices are for the passage of fixing screws, while the perforations (9) are to facilitate the alignment of the sections.

It does not alter the essentiality of this invention variations in materials, shape, size and arrangement of the component elements, described in a non-limiting manner, this being sufficient for reproduction by an expert.

Claims

1.- Polarization spinner between an input waveguide (6) and an output waveguide (7) whose respective axis (6.1) and (7.1) have between them an angle of β ° characterized in that between the guides of Input and output waves are interposed at least two sections (1) in a parallelepipedic manner, each of them having emptyings (2) that have a bow tie shape.

2. Polarization spinner according to claim 1, characterized in that the bow-shaped hollows (2) of the sections (1) have two planes of symmetry, one along a longitudinal axis (4) that run along the largest dimension of the bow tie, and another plane of transverse symmetry that runs along a transverse axis (5) to the previous one.

3. Polarization spinner according to claim 2, characterized in that each emptying in the form of a bow tie is defined by a series of parameters that allow the precise construction of said emptying, the parameters being Ra, Rb, La, Lb, Lc, and E and its longitudinal axis has an inclination angle relative to the axis of one of the waveguides.

4. Polarization spinner according to claim 3, characterized in that in case the number of sections (1) of the spinner is N, with N being an even number, the parameters defining the emptying (2) in the form of a bow tie of each one of the sections would be:

The ₁ ⁼ The. (tj-iti)

For i = 1,2, ..., N / 2

And all bow-shaped voids have their longitudinal axis with an angle D ₁ in relation to one of the axes of the input and output waveguides, and therefore the number of parameters necessary to define a spinner conformed by N sections, being N an even number is 7 * N / 2.

5.- Polarization spinner according to claim 3, characterized in that in case the number of sections (1) of the spinner is N, N being an odd number the parameters defining the voids (2) in the form of a bow tie Each of the sections would be:

For i = 1,2, ..., (N-I) / 2

and all bow-shaped hollows have their longitudinal axis with an angle B ₁ relative to one of the axes of the input and output waveguides, while the bow-shaped hollow of the section (N + l) / 2 has the following parameters. R-9- (N + l) / 2 Rb _{(N + l)} / ₂ La (N + l) / 2 Lb (N + l) / 2 LC (N + l) / 2

E (N + l) / 2

And it is turned β / 2 ° in relation to any of the axes of the input and output guides.

Therefore the number of parameters necessary to define a spinner consisting of N sections, where N is an odd number is 7 * [(N + l) / 2] -l

6. Rotator according to any of the preceding claims characterized in that the sections that make up the rotator have a series of perforations, where the four oblong perforations (8) of the vertices are for the passage of fixing screws, while the Perforations (9) are to facilitate the alignment of the sections.