JPH09116332A - Surface radiation type antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide high gain/wide band performance not to fluctuate the radiation center of radio wave even at the time of wide band usage. SOLUTION: A surface radiation type antenna has a rectangular frame-shaped antenna element 3, for which the ratio of length between a short side 1 and a long side 2 is set from 1:2 to 1:6 and the length of the long side 2 is almost set to be 1/2 as long as a wavelength to be used or set equal with the wavelength to be used, and is provided with totally two pairs of power feeding points 4, 4, 4 and 4, two by two on the respective long sides 2 and 2, at the positions almost from 1/3 to 1/8 of a full length from both ends on the respective long sides 2 and 2. Then, the antenna element 3 is cylindrically formed so that the respective long sides 2 can form the outer edges of upper and lower terminal parts and the height equal with the short side 1 can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna used for wireless communication.

[0002]

2. Description of the Related Art Most of antennas used for wireless communication are linear antennas which are one-dimensionally composed of metal conductors, as represented by a quarter-wavelength installed antenna and a half-wavelength dipole antenna. Is. The linear antenna has an 8-shaped horizontal directional pattern as typified by a standard dipole, and has non-uniform gain in directions, so that it is incomplete as an omnidirectional antenna.

Further, in order to increase the effective aperture area and efficiency of this linear antenna, a technique of arranging a plurality of parasitic elements in series to enhance the directivity and increase the gain, such as a Yagi antenna, or a reflector is used. There is also a technology for providing directivity by attaching it, but such a method results in the gain performance and the effective communication range (angle) being in inverse proportion, and especially in an antenna with a sharp directivity such as the Yagi antenna. Is limited to a narrow range of directional characteristics in order to narrow down radio waves in a certain direction, and is not suitable for use in a mobile vehicle whose positional relationship with a communication partner fluctuates.

In contrast to the above-mentioned linear antenna, the rectangular slot antenna has a generally high gain because radio waves are two-dimensionally radiated due to its planar shape. Among them, as shown in FIG. 3, a loop antenna or a shape similar to it is used. And the long side is 2
It has a rectangular frame-type antenna element whose short side is one-sixth to one-quarter wavelength, and is located at a position about one-quarter from the end on the same side on each long side. A field radiating antenna having a pair of feeding points (commonly called Hentenna) has a loose horizontal directivity pattern similar to a standard dipole when used alone without a reflection focusing system. As with the antenna, gain non-uniformity occurs in the direction. However, with regard to the numerical value of gain, the standard dipole ratio is +6 dB, and that of the one-wavelength type is +8 dB. In addition to having the functions of a standing wave type antenna and a traveling wave type antenna, it also has a wide band and has some degree of polarization diversity performance. It has many advantages such as

[0005]

When comparing the linear antenna element and the planar antenna element in this way, it can be said that the use of the planar antenna element is preferable in terms of gain. No matter which antenna is used, the frequency is 2.5 times the center frequency or 2.5 or more.
When it is used by expanding it to less than one-half, it has a drawback that the radiation center of the radio wave fluctuates and the directional pattern is disturbed.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a field radiating antenna having a high gain and wide band performance in which the radiation center of a radio wave does not change even when a wide band is used. To do.

[0007]

The surface radiating antenna according to the present invention made to solve the above-mentioned problems has a ratio of the length of the short side to the length of the long side of 1: 2 to 1: 6. Has a rectangular frame-shaped antenna element whose length is set to be half the used wavelength or equal to the used wavelength, and from about 1/3 of the total length from both ends on each long side. It is characterized in that two pairs of feeding points, two for each long side, are provided at one-eighth points, for each long side. In some cases, the antenna element is formed into a tubular shape in which each long side forms the outer edges of the upper and lower ends and has the same height as the short side.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a field radiation antenna according to the present invention will be described below in detail with reference to the drawings. In FIG. 1, the length of the long side 2 is set equal to the wavelength used, and the length of the short side 1 is set to
Has an antenna element 3 whose length is set to about 4: 1 to about 6: 1 with respect to the length of the long side 2, and a length of 4
For each of the long sides 2 and 2, two pairs of feeding points 4, 4, 4 and 4 are provided for each one of the long sides 2 and 2, and the feeding points 4, 4 and 4 are provided.
1 shows a first embodiment of a field-radiation-type antenna according to the present invention in which feeding paths 5, 5, 5, 5 are individually drawn from 4, 4.

The feeding point 4 has two long sides 2 of the antenna element 3.
It suffices to provide them at both ends of the power feeding members 14, 14 which are bridged to each other. Only the both ends are made of a conductive material, and both ends are connected through an intermediate portion 15 made of an insulating material to enhance strength. It is desirable that both ends of the power feeding members 14 and 14 are formed in conformity with the cross-sectional shape of the conductive material forming the antenna element 3 so that the power feeding members 14 and 14 can slide with a moderate resistance that does not easily cause displacement. . Incidentally, if the ratio of the long side 2 to the short side 1 of the antenna element 3 is set to 6: 1, the impedance adjustment becomes easy, and if it is set to 4: 1, it is suitable for exclusive use for reception.

By selectively using the feeding paths 5, 5, 5, 5 of the antenna element 3, this antenna is made to function as one plane-field radiation type antenna, or the plane-field radiation type antenna shown in FIG. Two of them can be made to function as if they exist in the same space in a state where the positions of the feeding points 4 and 4 can be changed. That is, the two pairs of feeding points 4, 4, 4, 4 are connected in parallel via the feeding paths 5, 5, 5, 5 to form the integrated feeding paths 6, 6 so that the same antenna element 3 has a high gain. It can also be used as an individual field radiation antenna. At that time, if the impedances are adjusted by changing the positions of the feeding points 4, 4, 4, 4 when the feeding paths 5, 5, 5, 5 are connected in parallel, a diversity effect occurs and the S / N ratio of the antenna is increased. It is also possible to improve the ratio. These effects are particularly remarkable when used for video reception. If two pairs of feeding points 4, 4, 4, 4 are divided into two in the longitudinal direction of the long side 2 of the antenna element 3 and selected one by one, each antenna has a relative gain of about +8 dB. The position of the center of radiation can be selected according to the situation. In either case, the impedance adjusting part and the radiating part are integrated, and the impedance can be matched by adjusting the position of the feeding point 4 along the long side 2 of the antenna element 3.

The antenna element 3 can be made of various conductive materials such as linear, tubular and flat (thin film) shapes. However, when it is made of a flat conductive material as shown in FIG. 2, the width of the conductive material is enlarged. By doing so, wide band performance can be obtained, and in the case of using a conductive material having a certain width, even if the operating frequency is set to a wide band ranging from about one-third to about three times the center frequency. , The radiation center of the radio wave is stable and operates well over the entire area. In particular, if the length of the inner side of the long side of the antenna element 3 is equal to the length of one wavelength depending on the center frequency to be used, it functions as a perfect standing wave type antenna similar to a slot antenna.

An antenna having added value to the surface radiation type antenna according to the present invention will be described below with reference to the drawings. FIG.
In the above, the surface radiating antenna is fixed to the central portion of the lattice-shaped flat reflecting plate 7 via an insulating material 16 so as to have directivity. By doing so, the antenna functions as a unidirectional directional antenna, and the relative gain is 1 or less.
It is improved to 0 dB to 15 dB. In addition, as described above, the field emission antenna according to the present invention has an advantage that the radiation pattern is extremely stable at the center of the antenna element even when the frequency used is changed to a relatively wide range, so that the directional pattern is extremely stable. is there.

5 and 6 show the directivity by fixing the above-mentioned field radiating antenna to a lattice-shaped corner reflector 8 (the opening angle of which can be changed as required) through an insulating material 16. And is configured to realize high gain. By doing so, the directivity pattern is stable, and the frequency that can be suitably used functions as an ultra-wideband antenna that extends from about 1/10 to 10 times the center frequency. If the antenna is arranged so that the long side 2 of the antenna element 3 is along the direction of the corner reflector 8 as shown in FIG.
By selectively using 4 or 4, one antenna is suitable for short range reception (antenna for TV reception, etc.)
, Or as an antenna suitable for telecommunications. 5 and 6 are compared with each other by connecting to the integrated box 17 via the power feeding paths 5, 5, 5, 5 having substantially the same length and further connecting to the communication device via the integrated power feeding path 6. The structure is suitable for short-distance communication.

In FIG. 7, the field radiation antenna 9 is attached to the insulating plate 1 for the purpose of receiving satellite broadcasting.
A plurality of antennas are arranged side by side on one side and fixed, and the feeding path 5 of each antenna 9 is electrically integrated to obtain a high gain and a space diversity effect.

FIG. 8 shows a second embodiment of the field emission antenna according to the present invention. This antenna corresponds to the first embodiment described above (planar surface-field radiation antenna).
The long side 2 is bent by 90 degrees every quarter and the antenna is configured as a three-dimensionally uniform directional characteristic by the same method as forming a cube or a rectangular parallelepiped from a plane.

This antenna is constructed by using the long sides 2 and 2 of the antenna element 3 as upper and lower horizontal frames and the short side 1 as a vertical frame, and the feeding points 4, 4, 4, 4 of the long sides 2 and 2 are arranged. The power feeding paths 5 and 5 which also function as diagonally connecting reinforcing members are supported and electrically integrated by a pillar 10 made of a conductive material standing in the center of the antenna. Thus, the high frequency current guided from the antenna element 3 via the power feeding paths 5 and 5 is guided to the communication device (not shown) via the support column 10 which is an integrated power feeding path.

By integrating the two pairs of feeding points 4, 4, 4, 4 in this way, the gain and fidelity are improved, and the antenna element 3 is surrounded by the three-dimensional cube. The center of the space is the center of radiation, and the position of the center of radiation and the directivity pattern are stable over a wide band so that it can be used conveniently, and it also has directivity in almost all directions, and the gain is also centered. A relative gain of 8 dB can be obtained near the frequency.

As a result of assembling the above-mentioned structure, both short sides 1, 1 of the antenna element 3 come close to each other in parallel. However, both short sides 1, 1 should be supported so as to be separated from each other. 1,1
It is desirable to interpose a connecting tool 12 made of an insulating material between and to reinforce the corners. This antenna is PH
Although it can be used for many applications such as an S relay antenna and a TV receiving antenna, when it is used as a TV receiving indoor antenna, for example, a conductive material having a width of 3 cm is used and the outer dimensions are about 12.5 cm × 50.0 cm. Antenna element 3
To form a support base 1 made of an insulating material.
3, the antenna element 3 may be appropriately dimensioned, and the column 10 may be fixed to a house or the like via an insulating mounting member when used as an outdoor TV antenna. The three-dimensional surface-field radiation antenna according to the present invention is not limited to a cube and a rectangular parallelepiped, and for example, FIG.
As described above, if the planar field-radiation-type antenna is formed into a cylindrical shape in which the planar shape is a circle (annular shape), it can be configured as a substantially complete omnidirectional antenna.

FIG. 9 shows a structure in which the field radiation type antennas 9 according to the present invention are multiply arranged and used as a broadcasting antenna. In this antenna, four antennas 9 are used, and the short sides 1 of the antenna elements 3 of the respective antennas 9 are arranged in the horizontal direction with respect to the column 10 at positions different by 90 degrees. ing.

Such a three-dimensional surface radiation antenna has a high gain like the two-dimensional surface radiation antenna.
It has high sensitivity and (1) omnidirectional performance.
(2) There is no change in gain due to direction or positional relationship with the other party. (3) Can be used in a wide band. (4) The radiation pattern is stable. (5) The occupied area is small and the space for installation can be saved. (6) Production costs are low and assembly and transportation are easy. (7) Excellent in strength and suitable for outdoor installation. And so on.

[0021]

As described above, the use of the surface radiating antenna according to the first aspect of the present invention has the following effects as well as the main effect of stabilizing the center of radio wave radiation over a wide band. When used as a TV receiving antenna, high broadband performance, long-distance receiving ability, ghost prevention performance, and good S / N ratio are effective for faithful reproduction of received video and received sound, and satellite broadcasting (BS , CS) for receiving, there is an effect that the type of polarization plane can be freely changed due to the high receiving efficiency around the area. Even in the reception of FM broadcasting, there is an effect that faithful reproduction can be performed with an extremely small planar antenna as in the case of TV reception.

Mobile phone (including wireless telephone)
When it is used for, the high sensitivity (high gain) is exhibited, and the small size facilitates incorporation. Also,
When this antenna is used as a broadcast or mobile phone relay antenna in a tunnel, a service area can be obtained in a wide range and direction without taking up space, and the interruption of broadcast waves in the tunnel can be eliminated. . Similarly, attach this antenna to the glass surface above the public telephone box,
It can also be used as a relay antenna for wireless (parent-child) telephones.

In using from a car to a moving body such as an aircraft, TV reception, amateur radio, business radio, etc.
Despite its small size, it is possible to use multiple bands such as VHF and UHF wave bands with high gain. At that time, the area of the opening can be reduced. There is no interruption. Moreover, there is an advantage that there is little change in gain due to a change in the positional relationship with the communication partner. Further, when used as a ground antenna for aircraft, it is possible to capture radio waves coming from a wide angle by utilizing a gentle directional characteristic.

Further, the use of the surface radiating antenna according to the second aspect of the present invention has the following effects.
When used as a TV antenna, it can emit radio waves in multiple directions simultaneously over a wide band both indoors and outdoors, and can receive radio waves in multiple directions.
Receiving clearly with individual antennas. That is, even though the station is a fixed station, it is possible to cope with changes in the position of the other party of communication regarding VHF and UHF broadcasting including FM broadcasting and communication without changing the gain.

When it is mounted on land, sea, air, or transportation equipment, clear wireless communication becomes possible even under severe conditions such as relative relations with the other party of communication and obstacles to wireless communication peculiar to urban areas. If it is used for navigation and public works, its reach will be expanded compared to the conventional one. Especially when using HF and VHF at sea, not only high gain and high telecommunications capacity but also structural strength are obtained. Strong against wind and snow because it is excellent. Also, when installing in a car,
TV broadcasting can be suitably received simply by placing it near the window.

When used in a broadcasting antenna system, radio waves can be given to the area with uniform intensity. Therefore, the effect is high even when used for industrial applications including remote control and data transmission.

In this way, it is possible to quantitatively and qualitatively expand broadcasting and wireless communication services, and particularly, it is used in a wide range of applications such as expansion of TV broadcasting, telecommunications services, and multimedia system components, and is used for wireless devices. It is possible to enhance the role of the antenna as an important constituent element in use.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of a first embodiment of a field emission antenna according to the present invention.

FIG. 2 is a front view showing another example of the first embodiment of the field emission antenna according to the present invention.

FIG. 3 is a basic conceptual diagram of a conventional field emission antenna.

FIG. 4 is a front view showing an example in which a plane reflection plate is provided on the field emission antenna according to the present invention.

FIG. 5 is a front view showing an example in which a corner reflector is provided in the field emission antenna according to the present invention.

FIG. 6 is a front view showing another example in which a corner reflector is provided in the field emission antenna according to the present invention.

FIG. 7 is a front view showing an example in which a plurality of field emission antennas according to the present invention are arranged in parallel on an insulating plate.

FIG. 8 is a perspective view showing an example of a second embodiment of a surface radiation antenna according to the present invention.

FIG. 9 is a perspective view showing an example of an antenna having a multiple structure according to a second embodiment of a field emission antenna according to the present invention.

FIG. 10 is a perspective view showing another example of the second embodiment of the field emission antenna according to the present invention.

[Explanation of symbols]

 1 short side 2 long side 3 antenna element 4 feeding point

Claims (2)

[Claims] 1. The ratio of the length of the short side (1) to the length of the long side (2) is 1: 2 to 1: 6, and the length of the long side (2) is about 2 of the used wavelength.
Each of the long sides (2, 2) has a rectangular frame-shaped antenna element (3) set to have a length equal to a fraction or a length equal to the wavelength used.
About 1/3 to 1/8 of the total length from both ends above,
A field radiating antenna characterized in that two pairs of feeding points (4, 4, 4, 4) are provided for each long side (2, 2). 2. The antenna element (3) is formed in a tubular shape in which each long side (2) forms the outer edges of the upper and lower ends and has the same height as the short side (1). Claim 1
The described field radiation antenna.