ES2201020T3 - ORTHOGONAL POLARIZATION MONOLITICAL ANTENNA. - Google Patents

Abstract

Monolithic cross-polarized antenna, comprising a substantially rectangular reflector (2), radiating cells (1) mounted aligned on said reflector and each formed by two orthogonal dipoles (11; 12, 32), and a feeding system (20) which connects the two dipoles of said radiating cells to two external energy sources, each of the dipoles comprising two flat conductive elements (11A, B; 12A, B; 31A, B; 32A, B) bent in the form of "uve" , arranged on their backs and each presenting a central folding body (13, 33) fixed to the reflector by a first terminal part of said body and two lateral end arms (14, 15) protruding on both sides of a second opposite terminal part of said body, each of the two conductive elements of one of the dipoles of each of the cells being arranged between those of the other dipole of the same cell, characterized in that said power circuit (20) comprises s flat power supply lines (21, 22), mounted in front of said reflector (2) and connected to one and another of said sources respectively, and because a single first element (11A, 12A, 31A, 32A) of the two elements conductors of each of said dipoles comprises a bent conductive pin (17, 37) having a first integral end of the second terminal part of the central body (13, 33) of said first conductive element, extending into the "uve" and substantially along the central body of the second conductive element (11B, 12B, 32B) of the dipole, and having a second end connected to one of said feed lines (21, 22).

Description

Monolithic orthogonal polarization antenna.

The present invention relates to an antenna monolithic with cross polarization, specifically intended for cell phone.

The patent FR-A-2,766,626 reveals an antenna with cross polarization comprising dipoles mounted on a reflector, being orthogonal two to two and thus defining at least a radiating cell with cross polarization. This antenna preferably comprises several radiant cells with cross polarization, which are all constituted of the same shape and arranged on the same alignment along the reflector.

In this known antenna, the two elements Drivers of each of the dipoles are identical. They have the form of a "uve" and are mounted on their backs, being the bases of the "birds" in front of each other. Each one of them it presents a stile rigidly attached to the reflector and equipped with two lateral end arms opposite the reflector. Advantageously, they are manufactured in a single piece that is presented lower the shape of a conveniently trimmed plate and then folded in the form of "uve".

In this same known antenna, two dipoles are arranged orthogonally with respect to each other by being the two conductive elements of one of them interspersed between the two conductive elements of the other dipole, to define one of the radiating cells with cross polarization constituting a module Compact and robust radiant.

This known antenna also comprises a feeding system of your radiating cells with polarization crusade. This feeding system is double for feeding of the two cell dipoles from two sources power exteriors. It is constituted in any analogous way That is the dipole of each of the cells. It comprises a first section of coaxial cable attached to a coaxial connector connecting to one of the sources, second sections of coaxial cable joined each one by one of the cell dipoles and a power divider that connect the first section with the two second cable sections coaxial.

It is checked that a power supply system this type induces losses and can generate products of undesirable intermodulation, which are essentially due to numerous welded connections comprising this system of power, in particular for connection to the dipoles.

The present invention aims to minimize the drawbacks and simplify the power system of a compact cell antenna with cross polarization such as the mentioned above and, consequently, simplify the general antenna structure allowing to reduce considerably its cost.

The present invention aims at an antenna monolithic with cross polarization, comprising a reflector substantially rectangular, mounted radiating cells aligned on said reflector and each formed by two dipoles orthogonal, and a feeding system that connects the two dipoles of said radiating cells to two energy sources exterior, each of the dipoles comprising two elements flat bent "uve" conductors, arranged backs and each presenting a fixed central folding body to the reflector by a first terminal part of said body and two lateral end arms protruding on both sides of a second terminal part of said body, each being arranged of the two conductive elements of one of the dipoles of each of the cells between those of the other dipole of the same cell, characterized in that said power circuit comprises two flat power supply lines, mounted in front of said reflector and connected to both sources respectively, and because a single first element of the two conductive elements of each of said dipoles comprises a bent conductive pin having a first integral end of the second terminal part of the central body of said first conductive element, extending into the "uve" and substantially along the central body of the second element dipole conductor, and having a second end connected to a of said power lines.

Advantageously, this antenna also has at least one of the following characteristics:

- said flat conductor lines are located in front of a rear face of said reflector, being mounted said cells on an anterior face of said reflector,

- the solidarity sideburns of the first conductive elements of the two dipoles of the same cell radiant cross, without making contact with each other, in one part anterior of the cell and have the same orientations as one and another one of the cross polarizations of the cell,

- the pin is an integral part of said first conductive element,

- the pin is integral with the anterior end of the central body of said first conductive element and extends inside the "uve" and in front of the central body of the second dipole conductor element,

- the pin is integral to an intermediate zone of the second terminal part of the central body of said first element, is constituted by an axial cutting part of said central body, not completely separated from it, and extends to what length of the split axial part of the central body of the second conductive element of the dipole,

- each of the conductive lines have T-shaped forks with two lateral branches welded to the pins of the first two elements of two cell dipoles consecutive on said reflector, respectively,

- each of these conductive lines has a central extension, connecting the conductive line to one of The outside sources.

The characteristics and advantages of this invention will be deduced from an embodiment shown by title as a preferred but not limiting example in the attached drawings. In these drawings:

- Figure 1 is a front view of an antenna according to the invention,

- Figure 2 is a top view of a cell radiant of the antenna of figure 1,

- Figures 3 and 4 are two perspective views of two first conductive elements of both dipoles of each of the radiant cells,

- Figure 5 is a front view of one of the dipoles of each of the radiant cells,

- Figure 6 is a front view of the face rear of the antenna,

- Figures 7 and 8 show a variant of realization of the first two conductive elements of the Figures 3 and 4,

- Figure 9 shows the second element conductor, to be associated with the first element of figure 7 to constitute one of the dipoles of the radiating cells, and

- Figure 10 shows one of the dipoles according to This variant

With reference to figure 1, it is seen that the antenna comprises several identical radiant cells 1 with polarization crossed which are mounted being axially aligned on a reflector 2. These cells are four in the example shown but Your number could be different. Reflector 2 is flat with two longitudinal flanges 3 and 4 folded 90º to the same side as radiant cells 1.

With respect to figure 2, it is seen that each cell Radiant 1 comprises two orthogonal dipoles 11 and 12. Each one of the dipoles is formed by a pair of conductive elements 11A and 11B or 12A and 12B which have the form of "uve", being mounted the "birds" on their backs at a reduced distance one of other. The two lines have been drawn in dashed lines main polarization components of the fed dipoles, which are the two orthogonally crossed polarizations 5 and 6, and the Elements of the same dipole are in phase with each other. I know they also show, on only one of the conductive elements, the secondary polarization components 7A and 7B that are orthogonal to the main polarization of the dipole and are in phase opposition one with the other and, consequently, cancel directly. It has also been indicated with + and - the polarities of the elements of the dipoles for their radiation in radiofrequency waves according to a broadband diagram from electric power supplied by two exterior sources not represented.

The orientation in figure 1 of the cells radiant 1 on the reflector 2 is advantageously chosen so that cross polarizations 5 and 6 are only horizontal or vertical, this in order to optimize the characteristics of Transmission of the dipoles. These cross polarizations are preferably at + and -45º with respect to the longitudinal axis of the reflector, which corresponds to the vertical.

With reference to figures 2 to 5, it is highlighted that the conductive elements of the dipoles are constituted, advantageously, by conveniently trimmed and folded plates in the form of "uve".

Each of these conductive elements presents, as reference in figure 3 for element 12A, a body central 13 folded longitudinally and two terminal arms laterals 14 and 15, which arise from one of the terminal parts, in concrete of the previous part, of this body. It is planned to minus a tooth 16 at the other end of the body for assembly of the conductive element on the reflector. The central body presents in this embodiment two longitudinal folds that they thus divide into a flat axial part 13A, which constitutes a axial semiplane, and two wings such as 13B bent towards it side and length of the half plane. As a variant, you can present a single axial folding line.

One of only the two conductive elements of a same dipole, such as element 12A of dipole 12 and the element 11A of dipole 11, further comprises a pin 17 or 17 'which starts from the slightly lowered front end of the central body 13, or 13 'correspondingly for element 11A. This pin is  centered on the end of the body and is bent to extend in front and along the central body, being outside of the "uve" that defines this element 12A or 11A. This pin it is received inside the "uve" that defines the other element 12B of dipole 12 or 11B of dipole 11, where it extends to along and in front of the central body of this other element as It is visible in figures 2 or 5. This pin is part member of this conductive element or in a variant is added and It is welded at the front end of its central body.

In relation to figures 3 and 4, it is observed that the two conductive elements 12A and 11A only differ from one of the other by the previous recess 13C or 13'C where the pin 17 or 17 '. These two recesses, although shallow, They have different depths from each other. They thus allow pins 17 and 17 'cross at the front of the cell radiant, as visible in figure 2, but without making contact One with the other.

The length of the central body and the two arms of the different conductive elements equals a quarter of the wavelength of the energy radiated by each dipole. The different parts of the conductive elements of each of the dipoles constitute a symmetrical assembly for feeding with electric power from two outside sources not represented, to which dipoles are connected in the form that outlined below.

The mounting teeth 16 provided in the conductive elements are received in reflector 2 and welded to same, each by a welding point, such as 18 in the Figures 5 and 6. The end of pin 17 or 17 ', provided for only one of the two conductive elements of each dipole, is received at through the reflector, but it is isolated from it and is connected by a welding point 19 to a power circuit 20 of the dipoles.

This power circuit 20 is performed advantageously on the back of the reflector 2, as highlighted in figures 5 and 6. In a variant it can be carried out in the front part of the reflector, but is then associated with the supplementary decoupling elements between their different parts connected to the dipoles of the radiating cells.

It is constituted symmetrically with respect to longitudinal axis of reflector 2, being at a reduced distance Defined reflector. It comprises, thus, two power lines 21 and 22, each connected to one of the two sources Exteriors not shown. These two lines are parallel to the alignment of the radiating cells and are located by both parts of the direction of this alignment. Each of them presents two T-shaped forks that are planned in this example at both ends of this line. Thus, with reference to same time to figures 1 and 2, it is understood that the two branches 23 and 24 sides of one of the two forks, and the like from the other fork of line 21, each one is connected to the conductive element 11A of the dipoles 11 of four cells 1. Of the same way, the two branches of the bifurcations of line 22 are connect the conductive elements 12A of the dipoles 12 of the cells 1. The other conductive elements 11B and 12B of the dipoles 11 and 12 are, as far as they are concerned, connected electrically to reflector 2, connected to the ground of the two external sources of energy.

A connection extension 25 is provided in the middle part of each of the power lines, such as 21. This extension is used for the direct connection of one of the sources outside the midpoint of this line 21. In a variant, this extension is used for connection, through a section of cable coaxial, from the power line to a coaxial connector mounted at one end of the reflector and connected to one of the sources. Energy from outside sources is distribute conveniently to the different dipoles 11 and 12, obtaining the weights in amplitude and phase by variations of the feeding system parameters, namely of the distance of lines 21 and 22 and their bifurcations with with respect to reflector 2, and the length and width of these lines and forks.

These lines are flat electrical conductors, of the same nature as the reflector and that the elements conductors of dipoles 11 and 12, namely aluminum or aluminium alloy. They stay in front and at a distance required reflector by means of insulating spacers, not shown, which are provided between them and the reflector.

To complete the antenna description of according to the invention, in figure 6 the welding points 18 of the ends of the central bodies of the different conductive elements of the dipoles and the points of welding 19 of the supplementary pins provided in two of the Four conductive elements of each radiant cell. In the figure 2 the holes 29 of the pins have been schematized, such as 17 and 17 ', through the reflector, without making contact between these pins and the reflector.

It is necessary, finally, that they can be provided with advantageously insulating wedges, not shown, between each of the pins, such as 17 and 17 ', and the central body of the conductor element that receives the pin.

In the same way, they are planned advantageous one or more insulating wedges, not shown, between the solidary pin of the conductive element 11A and the solidary pin of the conductive element 12A, which intersect one below the other, but without making electrical contact between them, in the part anterior of each cell 1 (figure 2). The areas of these pins that intersect in the anterior part of the cell are oriented according the cross polarizations 5 and 6.

The advantages of the antenna structure monolithic described, when integrating the feeding system of the dipoles and thus suppressing numerous welding points, are deducted directly from the description of this preferred mode of realization. These advantages are especially the improvement of robustness, which minimizes losses in the system food and undesirable intermodulation products, and the significantly reducing the cost of the antenna.

In the embodiment variant shown in the Figures 7 and 8, in relation to Figures 3 and 4, the first two conductive elements, respectively, of the two dipoles of a same radiant cell are designated by 32A and 31A. The only ones differences in relation to the conductive elements 12A and 11A of Figures 3 and 4 are indicated below.

In this variant, the anterior end of the body central 33 or 33 'has no recess. On the contrary, in this central body is provided an axial opening 38 or 38 'that extends from an intermediate zone of its anterior terminal part to its rear end, in the length of the initial half plane between the two wings 33B or 33'B.

Pin 37 or 37 'of each of the elements conductors is formed by the axial cutting part of the opening, without detaching from the previous part 33 or 33 'which is what only remaining from the initial semiplane, and by bending twice of this axial cutting part. This pin extends, from this mode, outward of the "uve" and in front of the element driver who is supportive.

These figures 7 and 8 show that the bending point closest to the central body is at a level slightly different on the two pins 37 and 37 '. This allows the crossing these pins, without making contact, in the front of  the radiant cell.

Figure 9 shows the second conductive element 32B associated with the conductive element 32A of Figure 7 for constitute one of the dipoles indicated with 32 and shown in the Figure 10. It is emphasized that this second element 32B is analogous to conductive element 32A, except that it has no pin 37 of this. In concrete, its central body comprises an opening 38B, which extends for almost its entire length, to receive pin 37 without make contact between this pin and the conductive element 32B.

In a variant not shown, indicated by with respect to figure 9, instead of the aforementioned opening 38B, it can provide a simple hole in an intermediate area of the part anterior of the central body semiplane for insertion through of this pin hole 37 of element 32A of Figure 7 to inside the "uve" of the conductive element 32B as well modified. This pin 37 does not make contact with the element driver who receives it.

When the dipole 32 of Figure 10 is mounted on the reflector and then fed, as described above for dipoles 11 and 12 in relation to the figures 2, 5 and 6, pin 37 is at polarity + of one of the two external sources to give this polarity + to the element conductor 32A, while conductor element 32B is at polarity - given by the reflector connected to the mass of the outdoor fountains For finding this pin 37 in or practically at opening 38B, it results in a mode of coplanar radio power to almost-coplanar of the two conductive elements of this dipole 32.

Comparatively, the feeding mode of the two elements of each of the dipoles 11 and 12 above, such as of the dipole resulting from the suggested variant in relation to the Figure 9, is of the "microstrip" type, with a dielectric layer of  air of defined thickness between the conductive parts that have the + and - polarities, and are facing each other.

The advantage of the described embodiment variant in relation to figures 7 and 10 is that radiant cells like this obtained are lighter and lower cost, since the pin of one of the two conductive elements of each dipole is essentially the result of the cut of its central body and because The other element is the open mime.

Claims (13)

1. Monolithic cross-polarized antenna, comprising a substantially rectangular reflector (2), radiating cells (1) mounted aligned on said reflector and each formed by two orthogonal dipoles (11; 12, 32), and a feeding system ( 20) connecting the two dipoles of said radiating cells to two external energy sources, each of the dipoles comprising two flat conductor elements (11A, B; 12A, B; 31A, B; 32A, B) bent in the form of " uve ", arranged on their backs and each presenting a central folding body (13, 33) fixed to the reflector by a first terminal part of said body and two lateral end arms (14, 15) protruding from both parts of a second part opposite terminal of said body, each of the two conductive elements of one of the dipoles of each of the cells being arranged between those of the other dipole of the same cell, characterized in that said power circuit (20) comprises two flat power supply lines (21, 22), mounted in front of said reflector (2) and connected to one and another of said sources respectively, and because a single first element (11A, 12A, 31A, 32A) of the two elements conductors of each of said dipoles comprises a bent conductive pin (17, 37) having a first integral end of the second terminal part of the central body (13, 33) of said first conductive element, extending into the "uve" and substantially along the central body of the second conductive element (11B, 12B, 32B) of the dipole, and having a second end connected to one of said feed lines (21, 22). 2. Antenna according to claim 1, characterized in that said flat conductor lines (21, 22) are located in front of a rear face of said reflector (2), said cells being mounted on a front face of said reflector. 3. Antenna according to claim 2, characterized in that the pins (17, 17 '; 37, 37') in solidarity with the first conductive elements of the two dipoles of the same radiating cell (1) cross, without making contact between they, in an anterior part of the cell and have the same orientations as both of the cross polarizations (5, 6) of the cell. 4. Antenna according to claim 3, characterized in that the cross polarizations are substantially + and -45 ° with respect to the vertical, respectively. 5. Antenna according to one of claims 1 to 4, characterized in that said pins (17) pass through said reflector (2) without making contact with it, each through a hole (29) in the reflector, and are each welded to one of said flat conductor lines (21, 22). 6. Antenna according to one of claims 1 to 5, characterized in that the pin (17; 37) is an integral part of said first conductive element (11A; 32A). Antenna according to one of claims 1 to 6, characterized in that the central body of each conductive element has at least one end tooth (16) on said first terminal part thereof, which fits into said reflector and is welded thereto. . Antenna according to one of claims 1 to 6, characterized in that each of said conductive lines has T-shaped bifurcations, each with two lateral branches (23, 24) welded to the pins of two first elements of the dipoles of two consecutive cells on said reflector, respectively. 9. Antenna according to claim 8, characterized in that each of said conductive lines (21, 22) has a central extension (25), connecting the conductive line with one of the external sources. 10. Antenna according to claim 1, characterized in that the pin (17) is integral with an anterior end of the central body (13) of said first conductive element (11A; 12A). Antenna according to claim 1, characterized in that the central body (33) of each of said first and second conductive elements (32A; 32B) has an axial opening (38, 38B) extending between a rear end and an intermediate zone of said second terminal part thereof. Antenna according to claim 11, characterized in that the pin (37) of said first conductive element (32A) is integral with said intermediate zone of said second terminal part of the central body (33) thereof and is constituted by a part axial cutting of said opening (38) in said body. 13. Antenna according to one of claims 10 to 12, characterized in that the central body (13, 33) of each of said first and second conductive elements has an axial half plane and two lateral wings bent towards the same side of the half plane.