JPH07111418A - Plane antenna for polarized wave diversity - Google Patents

Abstract

PURPOSE:To obtain an inexpensive polarized wave diversity plane antenna of power density type with high reliability whose characteristic is stable. CONSTITUTION:A ring patch antenna is made up of a grounding plate 1, a ring patch 2 made of an aluminum plate, and four aluminum-made pipes 16, 16a short-circuiting the grounding plate 1 and the ring patch 2 and a feeding probe 6a of a feeding terminal 6 is coupled with a center of the ring patch 2. The notch antenna is made up of four notches 9 formed to the ring patch 2, a feeding probe 13a of a microstrip line 13 formed to a flexible printed circuit board 4 placed on the ring patch 2 via a foamed plastic sheet 3 and a feeding terminal 8 resulting from penetrating the feeding probe 8a pressed to a feeding point 13b of the microstrip line 13 via a pipe 16a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarization diversity plane antenna adapted to polarization diversity, which is mainly used for relay antennas, cellular antennas and the like of mobile communication systems such as digital telephones. .

[0002]

2. Description of the Related Art Conventionally, a monopole antenna has been widely used as an antenna used in a mobile communication system. However, the physical length is often required to be about ¼ or more of the used wavelength, and in some cases, it is not suitable for mounting on a high-speed moving body or for portable personal use. Therefore, lower profile has been desired for these applications.

As a low-profile antenna, a ring patch antenna (disc-loaded monopole antenna) in which the length of the monopole antenna is shortened and a disc-shaped disc is loaded
Is known from the following documents and the like. [Sekine, Uno, Sawaya, Adachi: "Theoretical Analysis of Disk-Loaded Folded Monopole Antenna", Theoretical Theory (B), J71-B, 11, pp. 12
44-1247 (1988-11)] [Kaneda, Kondo, Ando, Goto: "Axisymmetric mode annular patch antenna and its feeding method", IEICE Tech., AP87-53.
(1987-07)] It is impossible for the ring patch antennas disclosed in these documents to constitute a polarization diversity antenna by itself, and it is necessary to use a plurality of them in combination.

In view of this, a power density antenna having two types of antennas has been proposed in the following documents, etc. in order to achieve polarization diversity within a single antenna size. [Arai, Goto: "Plane diversity antenna for car phones", IEICE Technical Report AP89-12, pp29-3
2)] and Japanese Patent Laid-Open No. 2-218203, etc. In the above power density type planar antenna, a ring patch antenna and a notch (notch) are provided in the ring patch portion,
A notch antenna that feeds with a microstrip line is combined with the notch.

Specifically, a patch element having a notch on the back surface is formed, and a microstrip line having a pattern capable of supplying power to the notch portion is formed on the front surface by etching or the like to isolate a double-sided printed board on the ground board at regular intervals. And a plurality of short-circuit means for short-circuiting the patch element and the ground plate. The power density type planar antenna configured in this way enables low profile and polarization diversity.

[0006]

However, in the case of the above power density type planar antenna, the cost of the high frequency material (Teflon (registered trademark) plate etc.) used as a printed board is high, and a plurality of conventional monopole antennas are used. There was a problem that the cost was inferior to the case of using it. Furthermore, the characteristics of the two antennas (ring patch antenna and notch antenna) change due to the loss of the microstrip line that constitutes the notch antenna and unnecessary radiation from the feeding point, and the gain of the notch antenna is mainly the ring patch. In some cases, it was lower than the gain of the antenna.

The present invention has been made in view of the above problems, and an object thereof is to provide a power density type planar antenna for polarization diversity which is a composite of a ring patch antenna and a notch antenna and is inexpensive and has a characteristic. Is to provide a stable and highly reliable planar antenna for polarization diversity.

[0008]

In order to achieve the above object, in the invention of claim 1, a grounding plate, a ring patch which is arranged in parallel with the grounding plate with a certain distance therebetween, and a center of the ring patch. A short-circuit means for short-circuiting between a position on the ring patch equidistant from the center on two diameter lines passing through each other and a ground plate facing this position, and a center of the ring patch perpendicular to the ring patch surface. And a ring patch antenna composed of a feeding means for feeding to each other, and four apertures respectively opened at peripheral positions of the ring patch which cross two diameter lines which are orthogonal to each other through the center of the ring patch between adjacent short-circuiting means. In a planar antenna for polarization diversity consisting of notches and a notch antenna composed of microstrip lines feeding these notches, a ring patch A printed substrate having a microstrip line having a power supply capable of feeding probes each notch on the ring patch formed of a metal plate in which is arranged through the foamed plastic sheet.

According to a second aspect of the present invention, an outer conductor that short-circuits one of the short-circuiting means between the ground plate and the ring patch, and an inner conductor that penetrates the outer conductor and is electrically insulated from the outer conductor. And the tip of the inner conductor is passed through the ring patch and the foamed plastic sheet to face the feeding point of the microstrip line of the printed circuit board, and the printed circuit board is ringed by the fixing means provided in the vicinity of the short-circuiting means. The patch is pressed against the patch via the foamed plastic sheet to bring the feeding point of the microstrip line into close contact with the tip of the inner conductor, and the printed circuit board, foamed plastic sheet, ring patch, and ground plate are integrated using the remaining three short-circuit means. It is fixed.

According to the third aspect of the present invention, the peripheral length of the notch is set to about ½ of the used wavelength, and the feeding probe of the microstrip line feeding the notch is oriented in a pair facing each other through the center of the ring patch antenna. Are arranged in opposite directions and the distance between the pairs is about 1/2 of the used wavelength, and power is supplied to each power supply probe in the same phase from the power supply point of the microstrip line.

According to the fourth aspect of the invention, the power supply by the power supply probe of the microstrip line is limited to only one pair of the two pairs of notches formed so as to face each other via the center of the ring patch. In the invention of claim 5, the microstrip line feeding probe is formed and arranged so that the pair of feeding probes which rotate by 90 degrees from the center of the ring patch antenna and face each other through the center are in opposite directions. It was done.

In a sixth aspect of the present invention, a microstrip line feed probe is formed such that pairs facing each other via the center of the ring patch antenna are opposite in direction and are adjacent to each other in line symmetry. Is.

[0013]

According to the first aspect of the invention, since the ring patch of the ring patch antenna is a metal plate, its rigidity improves the grounding reliability of the short-circuiting means and stabilizes the characteristics, and also the grounding effect on the notch antenna. Since it can be improved, the characteristics of the notch antenna can be improved, and since the notch antenna is fed through the foamed plastic sheet, not only the feeding loss can be improved but also the band can be improved.

Further, the foamed plastic sheet lowers the effective dielectric constant, and it is not necessary to use an expensive high frequency material as the material of the printed circuit board forming the microstrip line, so that the cost can be reduced. Claim 2
According to the invention, since the connection portion for feeding power to the microstrip line of the notch antenna can be made without using soldering or the like, highly reliable connection can be performed, and the conductor for feeding power can be provided in the short-circuit means. Since it does not affect the ring patch antenna, and the short-circuiting means also serves as the fixing means of the antenna component, it is necessary to configure the fixing means with consideration so as not to affect the performance of the antenna. It can be eliminated and the structure can be simplified.

According to the third aspect of the present invention, the power in the front direction of the notch antenna is minimized, which is preferable in the case of constructing polarization diversity, and the power of the beam in the lateral direction is maximized, so that the ring patch Similarly, omnidirectionality can be achieved in the lateral direction. According to the invention of claim 4, the notch which is not fed by the feeding probe can be operated as a parasitic element, so that the notch antenna can be made non-directional in the lateral direction even by the microstrip line having a simplified pattern. Can be planned.

According to the invention of claim 5, the notch antenna can be made more omnidirectional in the lateral direction. According to the invention of claim 6, in the lateral directivity of the notch antenna, a null can be generated between each notch,
Therefore, the diversity effect can be enhanced by adjusting the null direction depending on the application.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 shows an exploded perspective view of the embodiment 1 with a part thereof omitted. This embodiment is used in a band of 1.8 to 2.0 GHz, and includes a ground plate 1 and a ring. Patch 2
The foamed plastic sheet 3, the film-shaped flexible printed circuit board 4, and the plastic sheet 5 are used as main components.

The ground plate 1 is a commercially available aluminum plate (2 m
(thickness m) is punched into a disk shape with a diameter of 120 mm, and the lower surface is fixed with a power supply terminal 6 made of an SMA connector having a probe penetrating from the lower surface side to the upper surface side with screws or the like. Through the center of and orthogonal to each other 2
Positions where short-circuiting means for short-circuiting with the ring patch 2 are respectively provided at positions 45 mm from the center on one diameter line, screw insertion holes 7 are provided at three of the positions, and screws are provided on the back side of the remaining one. Feeding probe 8a of the feeding terminal 8 for the notch antenna which is composed of the SMA connector fixedly arranged by
Is provided with a hole 7a. Further, another screw insertion hole 7b is provided on the same diameter line as the hole 7a, near the hole 7a, and at an outer position.

On the other hand, the ring patch 2 is formed by punching a commercially available aluminum plate (0.5 mm thick) into a disk having a diameter of 115 mm, passing through the center thereof and orthogonal to each other 2
Four notches 9 that open at the periphery intersecting one diameter line
So that the screw insertion hole 7, hole 7a, and fixing screw insertion hole 7b of the ground plate 1 are located concentrically above the ground plate 1 and at a substantially central position between the adjacent notches 9, 9. The screw insertion hole 10, the hole 10a, and the fixing screw insertion hole 10b are provided at positions where the holes 7, 7a, 7b face each other when they are arranged at the same time, and the power supply probe 6a of the power supply terminal 6 is coupled at the center. Holes 11 are provided.

The notches 9 are formed by punching so that adjacent ones are at a position of 90 degrees when viewed from the center of the ring patch 2, and the peripheral length is about 1/2 of the used wavelength, that is, 85 mm in this embodiment. , A trapezoidal cutout that is widened from the inside of the ring patch 2 toward the peripheral edge. The foamed plastic sheet 3 is formed by cutting out a 2 mm-thick plastic sheet foamed by air into a disk shape, and when the foamed plastic sheet 3 is placed concentrically on the ring patch 2, the screw insertion hole 10, hole 10a, Fixing screw insertion hole 10
Holes 12, 12a and 12b are formed at positions corresponding to b.

The flexible printed circuit board 4 is formed in a disk shape and is provided with a microstrip line 13 having a power supply probe 13a for supplying power to each of the notches 9, a foamed plastic sheet 3 and a disk shape. It is interposed between the plastic sheet 5 and the plastic sheet 5. In the microstrip line 13 of the present embodiment, as shown in FIG. 2, each feeding probe 13a is formed so as to be orthogonal to the diameter line passing through the center of the corresponding notch 9 and rotate every 90 degrees, and The pattern of the four feeding probes 13a is formed so that the pairs facing each other via the center of 9 are opposite in direction. Further, the feeding point 13b is provided so that the distance between the facing pairs of the feeding probes 13a becomes 85 mm corresponding to about ½ of the used wavelength and the feeding can be performed in the same phase to each feeding probe 13a. The pattern is formed so that the physical distances from are equal. The feeding point 13b is the hole 10a of the ring patch 2 when the flexible printed circuit board 4 is arranged on the ring patch 2 via the foamed plastic sheet 3 so that the feeding probe 13a is in a fixed position.
It is formed at a position opposite to.

Further, the flexible printed circuit board 4 is provided with holes 14 and 14b at positions where the screw insertion holes 10 and 10b face each other when the flexible printed circuit board 4 is placed at the fixed position. The plastic sheet 5 has a thickness of 1 mm, and like the flexible printed board 4, holes 15 and 15b are formed at positions facing the screw insertion holes 10 and 10b, respectively.

In this embodiment, therefore, the ring patch 2 is arranged concentrically with respect to the ground plate 1 with a constant space therebetween, and the ground plate 1 and the ring patch 2 are short-circuited by four short-circuiting means. The feeding probe 6a of the feeding terminal 6 of the ground plate 1 is joined to the hole 11 at the center of the ring patch 2 via the impedance adjuster 18. Here, the short-circuit means is, for example, an aluminum pipe 16 having an outer diameter of 5 mm and a length of 8 mm,
16a, which has a spacer for holding the space between the ground plate 1 and the ring patch 2 and also has a function as a fixing means for the constituent members, and three pipes arranged corresponding to each screw insertion hole 7a. A screw 17 is inserted from the lower surface side of the ground plate 1 into the ring patch 2 through the screw insertion hole 7, and the tip of the screw 17 is inserted from the screw insertion hole 10 of the ring patch 2 into the ring patch 2.
To the upper surface side of.

The feed probe 8a of the feed terminal 8 is inserted through the hole 7a as an inner conductor into the pipe 16a arranged at the position corresponding to the feed terminal 8, and the feed probe 8a is inserted from the hole 10a of the ring patch 2 to the ring patch. 2 is projected to the upper surface side. Further, the pipes 16 and 16a are provided between the hole 7b of the ground plate 1 and the hole 10b of the ring patch 2.
A pipe 16b made of the same material and having the same shape is interposed. A screw 17b is inserted into the pipe 16b from the lower surface of the ground plate 1 through the hole 7b, and the tip of the screw 17b is projected from the hole 10b of the ring patch 2 to the upper surface side of the ring patch 2.

The foamed plastic sheet 3 is placed on the ring patch 2 arranged above the ground plate 1 as described above, and the holes 12, 12a of the foamed plastic sheet 3 corresponding to the tips of the screws 17, 17b are placed. Inserts the tips of the screws 17 and 17b, and inserts the tip of the feeding probe 8a into the hole 12a of the feeding terminal 8 corresponding to the feeding probe 8a.

A flexible printed circuit board 4 is placed on the foamed plastic sheet 3. At this time, the screws 17, 17 protruding on the upper surface of the foamed plastic sheet 3
The tip of b is the holes 14, 14 of the flexible printed circuit board 4.
Placed on the foamed plastic sheet 3 so that the power feeding point 13b of the microstrip line 13 faces the hole 12a of the foamed plastic sheet 3 inserted into the power feeding terminal 8 through which the tip of the power feeding probe 8a of the power feeding terminal 8 is inserted. As a result, each feeding probe 13a of the microstrip line 13 is moved to each notch 9 of the ring patch 2 as shown in FIG.
Will be placed in a fixed position corresponding to.

In this state, the plastic sheet 5 is further placed on the flexible printed circuit board 4, and the screws 17, 17 are
The tip of b is inserted into the holes 15 and 15b to project onto the upper surface of the plastic sheet 5, and the nuts 19 and 19 are attached to the projecting tip.
By screwing and fastening each b, the ground plate 1 and the ring patch 2 by the screws 17, 17b and the nuts 19, 19b.
Then, the constituent members including the foamed plastic sheet 3, the flexible printed circuit board 4, and the plastic sheet 5 are sandwiched and fixed via the pipes 16, 16a, 16b. Since the flexible printed circuit board 4 is sandwiched and fixed between the plastic sheet 5 and the ring patch 2 while compressing the foamed plastic sheet 3, the power feeding probe 8a of the power feeding terminal 8 is pressure-bonded to the power feeding point 13b of the microstrip line 13. Will be joined together.

The antenna shown in FIG. 3 thus completed is a ring patch antenna composed of the ring patch 2, the feeding terminal 6 and the ground plate 1, and the notch 9 formed in the ring patch 2 and the flexible structure. Notch antennas are respectively constituted by the feeding probe 13a of the microstrip line 13 formed on the printed board 4, and a power density type planar antenna corresponding to polarization diversity is constituted as a whole.

When the characteristics of the thus obtained planar antenna of this embodiment were measured in the band of 1.8 to 2.0 GHz, the notch antenna and the ring patch antenna showed no directivity in the antenna plane. It was omnidirectional, and it was confirmed that the radiated power in the direction directly facing the antenna surface was suppressed. Also, the radiated power of both antennas is about the same,
It has been found that the antenna exhibits extremely good characteristics as an antenna for polarization diversity.

Although the pattern from the feeding point 13b of the microstrip line 13 to each feeding probe 13a is changed in FIG. 4, the obtained characteristics are the same. (Embodiment 2) In this embodiment, as shown in FIG. 5, the power supply probes 13a and 13a corresponding to only the pair of notches 9 and 9 facing each other through the center of the flexible printed circuit board 4 are provided, and the other pair of notches 9 are provided. , 9 is a flexible printed circuit board 4 on which a microstrip line 13 having no corresponding power supply probe is formed, and the distance between the power supply probes 13a is set to 85 mm which is about ½ of the used wavelength. In addition, the distances from the feeding point 13b to the feeding probes 13a, 13a are equidistant so that the power can be fed in the same phase.

In the antenna of this embodiment, the notches 9 constituting the notch antenna are strongly coupled to each other, and the parasitic notch 9 operates as a parasitic element. Therefore, antenna characteristics substantially equivalent to those of the first embodiment can be obtained. Was given. As described above, in the present embodiment, as compared with the case of the first embodiment, the simple operation of the microstrip line 13 enables the good operation, and the stabilization of the characteristic and the redundancy of the design can be secured.

In FIG. 6, a vertically polarized radio wave is transmitted from a transmitter arranged at a fixed distance from the antenna of this embodiment arranged so that the patch surface is horizontal, and the antenna of the embodiment is 360 The result of measuring the change in the reception level of the ring patch antenna when it is rotated horizontally is shown. From these results, the ring patch antenna in this embodiment can obtain substantially the same reception level in any direction of 360 °. Therefore, it can be seen that it is omnidirectional.

Further, FIG. 7 shows that the transmitter of the present embodiment, which is arranged at a certain distance from the antenna of the present embodiment arranged so that the patch surface is horizontal, transmits the horizontally polarized radio wave, and the antenna of the embodiment is The result of measuring the change in the reception level of the notch antenna when rotated horizontally by 360 degrees is shown. From these results, the reception level of the notch antenna in this embodiment is extremely lowered in any direction of 360 °. It can be seen that it is almost omnidirectional.

FIG. 8 shows that a horizontally polarized radio wave is transmitted from a transmitter arranged at a certain distance from the antenna of this embodiment arranged so that the surface of the plastic sheet 5 is in the front direction and vertically. The results of measuring the change in the reception level of the notch antenna when the example antenna is rotated 180 degrees from the side opening on one side to the side opening on the opposite side are shown. It can be seen that the reception level is extremely lowered when facing the direction (front direction) X orthogonal to the transmission direction of the transmitter. That is, the notch antenna of this embodiment does not emit radiation in the front direction.

(Embodiment 3) In this embodiment, as shown in FIG. 9, power supply probes 13a and 13a for supplying power to a pair of notches 9 and 9 facing each other through the center of the flexible printed circuit board 4, Using the microstrip line 13 in which each pattern is formed so that the other pair of notches 9 and the feeding probes 13a ′ and 13a ′ for feeding the notches are symmetrical with respect to the diameter line passing through the center. Is.

In the case of the present embodiment, the feeding probes facing each other through the center of the flexible printed circuit board 4 are in opposite directions and are in axial symmetry with the neighboring feeding probes, and the feeding probes facing each other through the center. The distance between them is set to 85 mm, which is about ½ of the wavelength used, and the four feeding probes 13a, 13a, 13 from the feeding point 13b.
Physically equidistantly formed so that power can be supplied to a'and 13a 'in the same phase.

Thus, in the antenna of this embodiment, since the adjacent feed probes 13a, 13a 'face each other,
In the directivity in the water surface of the notch antenna, a null point will be generated between each notch 9, and if the direction of the null point is directed to the direction of the interfering radio wave and it is grounded, the reception reliability of the desired radio wave can be significantly improved. There is a feature called.

In FIG. 10, a horizontally polarized radio wave is transmitted from a transmitter arranged at a position a certain distance away from the antenna of this embodiment arranged so that the patch surface is horizontal, and the antenna of the embodiment is 360 It shows the result of measuring the change in the reception level of the notch antenna when it is rotated horizontally, and it can be seen from this result that the notch antenna in this embodiment has a null point at which the reception level decreases. .

The directional characteristics of the ring patch antenna and the radiation characteristics of the notch antenna in the front direction are the same as those in the second embodiment, and will be omitted. (Embodiment 4) In each of Embodiments 1 to 3 described above, the microstrip line 13 is formed on the flexible printed board 4, but in this embodiment, a commercially available single-sided copper-clad printed board 4'is shown in FIG. A microstrip line 13 is formed by etching using (1 mm thickness), and by utilizing the rigidity of the substrate, it also serves as the plastic sheet 5 used in Examples 1 to 3 above. It is composed.

In this embodiment, the pattern of the microstrip line 13 was formed in the same pattern as that of the first embodiment, and the antenna characteristic similar to that of the first embodiment was obtained. Further, the cost is reduced as compared with the first embodiment. Needless to say, if the pattern of the microstrip line 13 is replaced with the pattern of the second or third embodiment, the antenna characteristics similar to those of the second or third embodiment can be obtained.

[0041]

According to the present invention, a ring patch is formed of a metal plate, and a microstrip line having a feeding probe capable of feeding power to each notch is formed on the ring patch. Since it is arranged through, the rigidity of the ring patch made of a metal plate improves the grounding reliability of the short-circuiting means and stabilizes the characteristics,
In addition, because the grounding effect on the notch antenna can be improved, the characteristics of the notch antenna can be improved, and since the notch antenna is fed through the foamed plastic sheet,
The foamed plastic sheet lowers the effective permittivity to improve the feed loss, and also improves the band. Therefore, the characteristics of the notch antenna and the characteristics of the ring patch antenna can be made approximately the same. As a result, the antenna has an ideal shape as a polarization diversity antenna, and there is no need to use an expensive high-frequency material for the printed circuit board forming the microstrip line by the foamed plastic sheet, and the cost can be reduced.

According to a second aspect of the present invention, in the first aspect of the present invention, the outer conductor that short-circuits one of the short-circuiting means between the ground plate and the ring patch, and the outer conductor that penetrates the outer conductor is an electrical conductor. And an electrically conductive inner conductor, the tip of the inner conductor is made to pass through the ring patch and the foamed plastic sheet so as to face the feeding point of the microstrip line of the printed circuit board, and is provided in the vicinity of the short-circuit means. The fixing means presses the printed circuit board against the ring patch via the foamed plastic sheet to bring the feeding point of the microstrip line into close contact with the tip of the inner conductor, and the remaining three short-circuiting means are used to form the printed circuit board, the foamed plastic sheet, Since the ring patch and the ground plate are integrally fixed, the coupling for power feeding to the microstrip line of the notch antenna can be performed without using soldering, etc. Because, can a reliable connection,
Moreover, since the conductor for feeding power passes through the short-circuit means, it does not affect the ring patch antenna, and the short-circuit means also serves as a fixing means for the antenna constituent members, which does not affect the antenna performance. There is no need to consider the structure of the fixing means, and the structure can be simplified.

According to a third aspect of the present invention, in the first aspect of the present invention, the peripheral length of the notch is set to about ½ of the used wavelength, and the microstrip line feeding probe feeding the notch is provided through the center of the ring patch antenna. Are facing each other in opposite directions, and the distance between pairs is about 1 of the wavelength used.
It is formed and arranged so that it becomes / 2, and power is fed to each feeding probe in the same phase from the feeding point of the microstrip line.
Since the power in the front direction of the notch antenna is the minimum, it is preferable when configuring polarization diversity, and the power of the beam in the horizontal direction is the maximum, and the omnidirectionality in the horizontal direction is achieved like the ring patch. The effect is that you can.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the power supply by the microstrip line power supply probe is limited to only one pair of the two pairs of notches formed so as to face each other via the center of the ring patch. Therefore, the notch that is not fed by the feeding probe can be operated as a parasitic element, so that the notch antenna can be made omnidirectional in the lateral direction even in a microstrip line having a simplified pattern.

According to a fifth aspect of the present invention, in the third aspect of the invention, the feeding probe of the microstrip line is rotated by 90 degrees from the center of the ring patch antenna, and a pair of feeding probes facing each other through the center are provided. Since the notch antenna is formed and arranged so as to face in the opposite direction, there is an effect that the notch antenna can be made more omnidirectional in the lateral direction.

According to a sixth aspect of the present invention, in the third aspect of the present invention, the microstripline feed probes are line-symmetrical such that the pairs facing each other through the center of the ring patch antenna have opposite directions. Since it was formed so that in the lateral directivity of the notch antenna,
A null can be generated between each notch, and therefore, the diversity effect can be enhanced by adjusting the null direction according to the application.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a first embodiment of the present invention with a part omitted.

FIG. 2 is an explanatory diagram of a relationship between a notch of the above notch antenna and a feeding probe.

FIG. 3 is a side view of the above.

FIG. 4 is an explanatory diagram of a relationship between a notch of another notch antenna of the above and a feeding probe.

FIG. 5 is a diagram illustrating the relationship between the notch of the notch antenna and the feeding probe according to the second embodiment of the present invention.

FIG. 6 is an explanatory view of measurement results showing horizontal directivity of the ring patch antenna of the above.

FIG. 7 is an explanatory diagram of measurement results showing the horizontal directivity of the above notch antenna.

FIG. 8 is an explanatory diagram of measurement results showing directivity in the front direction of the notch antenna of the above.

FIG. 9 is a diagram illustrating the relationship between the notch of the notch antenna and the feeding probe according to the third embodiment of the present invention.

FIG. 10 is an explanatory diagram of measurement results showing the directivity in the lateral direction of the notch antenna of the above.

FIG. 11 is an exploded perspective view of a fourth embodiment of the present invention with a part thereof omitted.

[Explanation of symbols]

 1 Ground Plate 2 Ring Patch 3 Foamed Plastic Sheet 4 Flexible Printed Circuit Board 5 Plastic Sheet 6 Feeding Terminal 6a Feeding Probe 8 Feeding Terminal 8a Feeding Probe 9 Notch 13 Microstripline 13a Feeding Probe 13b Feeding Point 16, 16a, 16b Pipe 17, 17b Screw

Claims (6)

[Claims] 1. A grounding plate, a ring patch which is arranged in parallel with the grounding plate at a predetermined distance, and a ring patch which is equidistant from the center of the ring patch on two diametrical lines which are orthogonal to each other and pass through the center of the ring patch. Between a short-circuit means and a grounding plate facing this position, and a ring patch antenna composed of a power supply means for supplying power to the center of the ring patch perpendicular to the ring patch surface, and between adjacent short-circuit means. At the periphery of the ring patch that intersects the two meridians that intersect each other at right angles through the center of the ring patch.
In a planar antenna for polarization diversity consisting of one notch and a notch antenna composed of microstrip lines feeding these notches, it is possible to feed each notch on this ring patch by forming a ring patch with a metal plate A planar antenna for polarization diversity, wherein a printed circuit board on which a microstrip line having various feeding probes is formed is arranged via a foamed plastic sheet. 2. One of the short-circuiting means is composed of an outer conductor short-circuiting between the ground plate and the ring patch, and an inner conductor penetrating the outer conductor and electrically insulated from the outer conductor, The tip of the inner conductor is passed through the ring patch and the foamed plastic sheet to face the feeding point of the microstrip line of the printed circuit board, and the printed circuit board is foamed with respect to the ring patch by the fixing means provided in the vicinity of the short-circuiting means. By pressing through the plastic sheet to bring the feeding point of the microstrip line into close contact with the tip of the inner conductor, the remaining three short-circuit means are used to form the printed circuit board, the foamed plastic sheet,
The plane antenna for polarization diversity according to claim 1, wherein the ring patch and the ground plate are integrally fixed. 3. A peripheral length of the notch is set to about ½ of the used wavelength, and the feeding probe of the microstrip line for feeding the notch is arranged such that the pairs facing each other through the center of the ring patch antenna have opposite directions. 2. The polarization diversity plane according to claim 1, wherein the pair of pairs are formed and arranged so that the distance between them is about 1/2 of the used wavelength, and power is fed to each feeding probe in the same phase from the feeding point of the microstrip line. antenna. 4. The polarized wave according to claim 3, wherein the power supply by the power supply probe of the microstrip line is performed only for one of the two pairs of notches formed so as to face each other via the center of the ring patch. Planar antenna for diversity. 5. A microstrip line feeding probe is formed and arranged so as to rotate by 90 degrees with respect to the center of the ring patch antenna and the pair of feeding probes facing each other through the center are oriented in opposite directions. The planar antenna for polarization diversity according to claim 3. 6. A microstrip line feed probe is formed such that pairs facing each other via the center of a ring patch antenna are in opposite directions and adjacent ones are line-symmetrical to each other. Item 3. A planar antenna for polarization diversity according to Item 3.