JPH03270304A - Multi-frequency common use plane antenna - Google Patents

Abstract

PURPOSE:To cover a broad range frequency area by arranging plural radiation elements for high frequency range or radiation elements for medium frequency in the region formed by radiating elements for low frequency range of a microstrip antenna. CONSTITUTION:Two square cutout windows are arranged in the region formed by radiation elements 2 for low frequency range of a microstrip antenna comprising a ground plane 9 and the element 2 opposite to each other via a 1st dielectric body 6. Moreover, each of radiation elements 3 for high frequency range is arranged to each cutout window region while the elements 3 are parted to some degree from the end of each element 3 so that the element 3 does not contribute to the antenna characteristic. In such a case, when the antenna is used as a 2-frequency common use antenna, since the inter-center distance of each radiation element is smaller than the effective wavelength lambda of a wave in the dielectric body, the antenna is able to suppress the grating lobe. Thus, a broader frequency range is covered.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an array antenna used in a wireless communication device such as satellite communication or an antenna that uses a wide frequency range.

[Summary of the invention]

The multi-frequency shared planar antenna of the present invention is highly useful as a single element by arranging a plurality of high-frequency radiating elements or mid-range radiating elements in the internal area of the low-frequency radiating element of the microstrip antenna. Along with becoming an antenna,
This element antenna is also highly useful for array antennas. Also, it becomes possible to easily utilize multiple frequencies.

[Conventional technology]

Conventionally, the radiating element of a standard microslip antenna can be treated as a λ/2-based radiating element.

In addition, by short-circuiting one side of the radiating element and the ground plane, it can be treated as a λ/4-based radiating element (λ: effective wavelength in dielectric material), so it can be treated as a radiating element of a normal standard microstrip antenna. For 1/
An aperture area of 2 or less provides the same resonant frequency. Furthermore, by reducing the width of the short-circuiting conductor that short-circuits one side of the radiating element and the Guérande Bone, inductance is equivalently loaded, which leads to a reduction in the resonant frequency, and thus the antenna body can be made smaller. 6 As shown in Fig. 2, in a stacked micro-strinb antenna, one side of each radiating element 12° 13 is short-circuited across the entire surface or the width dimension of the short-circuit conductor 10 is controlled, and the first radiating element 12 and the second radiating element 12 are connected to each other. By utilizing the coupling between the elements 13, dual frequency common characteristics were obtained.

Here, in order to obtain three-frequency common characteristics, the third radiating element 14 is arranged on the same plane as the first radiating element 12 of the stacked microstrip antenna with a certain distance between the radiating elements, and the second This could be obtained by installing the power supply system 15.

Furthermore, with respect to element antennas for array antennas that have dual frequency characteristics, radiating elements having different resonance frequencies are arranged on the same plane with a certain distance between the radiating elements.

[Problem to be solved by the invention]

Element antennas for 3-frequency common antennas or 2-frequency common array antennas as mentioned above are arranged on the same plane with each radiating element dimension and a certain distance between the radiating elements, so the antenna body can be made smaller. It has the disadvantage that it is difficult to Further, in a stacked microstrip antenna, it is difficult to short-circuit one side of each radiating element and the ground plane with a shorting conductor, and it is also costly.

[Means to solve the problem]

In order to solve the above problems, in the present invention, a plurality of high frequency radiating elements or middle frequency radiating elements are arranged in the internal region of the low frequency radiating element.

[Effect]

When using a dual-frequency antenna at the bottom of the tank as described above, the distance between the centers of each radiating element is smaller than λ, so
The antenna can suppress grating lobes,
When a three-frequency antenna is used, a wide frequency range can be covered by appropriately controlling the dimensions of each radiating element.

〔Example〕

The present invention will be explained below based on the drawings.

In FIG. 1, the internal area of the low-frequency radiating element 2 of the microstrip antenna is formed at the bottom of the tank by installing the ground plane 9 and the low-frequency radiating element 2 facing each other with the first dielectric 6 in between. Place two rectangular cut windows in the area. By arranging this cut window, it is possible to lower the resonant frequency and to secure a space for arranging radiating elements having different resonant frequencies. In FIG. 3, the thickness of the first dielectric 6 and the second dielectric 7 is h, and the wavelength in free space is λ.
Then, when h/λ = around 0.01, aspect ratio is 1.5, and relative dielectric constant εr = 2.55, it is perpendicular to the dimension a, which is the long side of the low-frequency radiating element 2. Assuming that the rectangular punch is divided into two equal parts, the deviation of the resonant frequency when changing the dimensions of the cut window from the center of the square punch divided into two equal parts is calculated as the resonance of the low-frequency radiating element without the cut window. frequency f
It is normalized and expressed by 0. From this figure, if the short side of the low-frequency radiating element is b, and the dimension of one side of the rectangle that is the cut window is 50, the resonance frequency when so/b = 0.45 is compared to when there is no cut window. It can be seen that this is approximately 25% lower. Furthermore, since the high-frequency radiating element 3 or the middle-frequency radiating element 4 is arranged within the region of this cut window, the antenna main body can be made smaller. In FIG. 1(A), two notched windows are arranged in the internal area of the low-frequency radiating element 2, and antenna characteristics are further measured from the end of the low-frequency radiating element 2 within the area of each notched window. The high-frequency radiating elements 3 are arranged one by one at a certain distance so as not to contribute to the noise. At this time, in the two high-frequency radiating elements 3, by installing a shorting stub 5 at the part where the low-frequency radiating element 2 becomes an electrically short-circuited surface, the cross-polarized wave of the high-frequency radiating element 3 is components are suppressed. Next, two excitation slots 8 are arranged in the ground plane 9 so as to be parallel to the portion where the low-frequency radiating element 2 is electrically shorted. Furthermore, by installing the ground plane 9 and the microstrip line 1b for slot power feeding so as to face each other orthogonally to the excitation slot 8 via the second dielectric 7, the high frequency radiating element 3 can be connected via the slot. Power is supplied through electromagnetic coupling with the power supply microstrip line 1b. In this way
By feeding power to each independently, dual frequency sharing is realized. At this time, since the center-to-center distance between the radiating elements 7 of the high-frequency radiating element 3 is smaller than λ (λ two effective wavelengths), it is difficult to suppress the realizable.

In FIG. 1(B), two cut windows are arranged in the internal area of the low-frequency radiating element 2, and antenna characteristics are further measured from the end of the low-frequency radiating element 2 within the area of each cut window. One high-frequency radiating element 3 and one mid-range radiating element 4 are arranged to the extent that they do not contribute to the radiating element. Here, in the Nakagusuku radio element 7'-4, the copper plate (or copper foil) ior,
By shorting this to the ground plane 6 by electrical means, for example by soldering, an inductance is loaded, so it is possible to lower the resonance frequency. Furthermore, by controlling the width dimension of the short-circuiting conductor 10, the amount of inductance loaded can be varied, making it possible to easily obtain a desired resonance frequency. Further, the shorting stub 5 is arranged in the high frequency radiating element 3 to which slot power is fed, but the shorting stub 5 is not arranged in the middle frequency radiating element 4 to which coaxial power is fed.

This is because the mid-range radiator 4 is short-circuited with the existing radiator antenna 9, and if the short-circuit stub 5 is further provided, the antenna characteristics will be degraded.

By supplying power to each L2 independently in this way, 3
This will result in frequency sharing. In FIG. 1(A) and FIG. 1(B), Gerandbu 1.・When installing the slot power supply micros I/lithop line 1b via the second dielectric 7, it is necessary to make sure that the geland tube 1/- 9 and the second dielectric 7 are in complete contact with each other. There is.

For example, adhesion methods include adhesive, crimping with insulators,
One idea is to use a screw that passes through a dielectric portion that does not contribute to the antenna characteristics from the end of the low-frequency radiating element 2 to some extent.

In FIG. 1(C), two notched windows are arranged in the internal area of the low-frequency radiating element 2, and antenna characteristics are further measured from the end of the low-frequency radiating element 2 within the area of each notched window. One high-frequency radiating element 3 and one mid-frequency radiating element 4 are arranged in a manner similar to each other to some extent so as not to contribute to the above. At this time, since both the high-frequency radiating element 3 and the mid-range radiating element 3 to which coaxial power is fed are short-circuited to the ground plane 9 by the copper plate 104, the shorting stub 5 is not disposed. By controlling the dimensions of each radiating element and the width of the shorting conductor, a desired resonant frequency can be easily obtained. By feeding power to each independently in this way, three frequencies can be shared. Further, FIG. 1(C) is distantly related to FIG. 1(A) and FIG. 1(B) in that the second dielectric 7 is not provided, so that the thickness is reduced. Figure 4 (A) is the same as Figure 1 (A).
Figure (B) is Figure 1 (B), Figure 4 (C) is Figure 1 (C)
In the example shown in , the radiation pattern characteristics of each radiating element are shown.

In the present invention, power is fed to the low-frequency radiating element 2 by coplanar offset power feeding using a 50Ω microstrip line 1a, but coplanar direct-coupled power feeding and coaxial power feeding are also possible. Effects] As described in 2 below, according to the configuration based on the present invention, in the case of a dual-frequency antenna, it is possible to suppress the group 1/itening globe, so that the configuration based on the present invention can suppress the In the case of a 3-frequency shared antenna, it is possible to cover a wide frequency range, so
It is ideal as an antenna for a wireless communication device that uses multiple frequencies, especially multiple frequencies that are spaced apart.

[Brief explanation of drawings]

FIG. 1(A) is an exploded perspective view of the first embodiment of the present invention, FIG. 1(B) is an exploded perspective view of the second embodiment of the present invention, and 11EI(C) is an exploded perspective view of the first embodiment of the present invention. Fig. 2 is an exploded perspective view of the third embodiment, Fig. 2 is a perspective view of the conventional example, and Fig. 3 shows the deviation of the resonant frequency when the dimensions of the window cut into the internal region of the low-frequency radiating element are changed. 4(A) is a radiation pattern characteristic diagram of the first embodiment of the present invention, FIG. 4(B) is a radiation pattern characteristic diagram of the second embodiment of the present invention, FIG. C) is a radiation pattern characteristic diagram of the third embodiment of the present invention. 1a... Microstrino line for off-cent power supply Slot Microstrip line for power supply Radiating element for low range Radiating element for high range Radiating element for mid range Short-circuit stub First dielectric Second dielectric Slot for excitation Ground plane Short circuit Conductor coaxial feeder First radiating element Second radiating element Third radiating element Second feeding system Above the feeding point 0.3 0.4 0.5 (Sq/b) Inmoto Kabuto June Ha 1st Ha Figure 1 (A) Second Hades of the present invention ``・1 High'' Kaku Haya #'t? Diagram Figure 1 (B) (b) High range MSA for 1/1 of the present invention

Claims (1)

[Claims] A microstrip antenna is constructed by installing a ground plane and a low frequency radiating element facing each other with a first dielectric interposed therebetween, and a plurality of high frequency A multi-frequency common planar antenna characterized by arranging a radiating element for the middle range or a radiating element for the middle range.