JPH05175719A - Manufacture of microstrip antenna and adjustment method for resonance frequency - Google Patents

Abstract

PURPOSE:To obtain the microstrip antenna whose accuracy is excellent and whose adjustment is easy. CONSTITUTION:An end of an electrode film being a radiation electrode 11 formed on the surface of a square dielectric board 10 is cut off at a groove 15 formed on the surface of the dielectric board 10 to set a prescribed size or a size by which a desired frequency is obtained. Or the electrode film formed on the entire surface of the dielectric board is removed by the surface polishment of the dielectric board to match the film to a prescribed size.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a microstrip antenna used in a navigation system and a method for adjusting a resonance frequency. The manufacturing method and resonance are easy to manufacture and the resonance frequency can be easily adjusted. It relates to frequency adjustment.

[0002]

2. Description of the Related Art In a GPS navigation system or the like, a small antenna for receiving a signal from a satellite is required, and use of a microstrip antenna is considered as one of them.

In this microstrip antenna, a radiation electrode having a size of ½ of the wavelength to be received is formed on the front surface of a dielectric substrate, and a ground electrode is formed on the entire back surface.
There are square and circular radiating electrodes, and by devising their shape, the receiving frequency can be broadened.

FIG. 3 is a front view showing an example of the structure of such a microstrip antenna. Dielectric substrate 30
The radiation electrode 31 is formed on the front surface of the and the ground electrode 32 is formed on the back surface. From the 50Ω point of the radiation electrode 31, a conductor is drawn out to the back surface through the through hole and connected to the coaxial line. When the radiation electrode is formed by a rectangular electrode, its size is determined by the resonance frequency, the effective dielectric constant of the dielectric substrate, and the speed of light.

[0005]

In the actual manufacture of the microstrip antenna designed and manufactured as described above, it is necessary to adjust the resonance frequency due to variations in the characteristics of the ceramic dielectric, and the electrode is generally used. The work of fitting is done by scraping. However, it is difficult to finely adjust the frequency, which is a major factor in the increase in man-hours.

The electrodes of silver or copper are usually formed by printing and printing. In the case of printing, it becomes difficult to secure dimensional accuracy. Further, when the electrodes are formed by the photolithography technique, the accuracy is improved, but the cost is significantly increased.

The present invention provides a manufacturing method and a resonance frequency adjusting method that can be manufactured at low cost, can adjust the resonance frequency, and have good accuracy.

[0008]

The present invention solves the above problems by forming a radiation electrode by grinding.

That is, in a method of manufacturing a microstrip antenna or a resonance frequency adjusting method, in which a radiating electrode having a half wavelength is provided on the surface of a dielectric substrate and a ground electrode is provided on the entire back surface, An electrode film is formed in the center part, and a groove extending parallel to the end surface of the dielectric substrate is formed at the end part of the electrode film, and the size of the electrode film is adjusted by the formation of this groove. The feature is that the wavelength is halved.

Further, the surface of the dielectric substrate has a half wavelength
In the method of manufacturing a microstrip antenna or the method of adjusting the resonance frequency, which includes a radiation electrode and a ground electrode on the entire back surface, an electrode film is formed on the surface of the dielectric substrate, and the electrode film is centered from the end surface of the dielectric substrate. This is characterized in that the dielectric is exposed by grinding toward the portion and an electrode having a size of ½ of the wavelength is formed in the central portion of the surface of the dielectric substrate.

[0011]

When a high-precision cutter is used, grinding with an accuracy of about 5 μm is possible. As a result, the accuracy can be improved as compared with the case of printing, and it is possible to obtain an electrode size that enables reception of a predetermined resonance frequency.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a (a) front view and a (b) plan view showing an embodiment of the present invention. It is formed on a 30 mm square of a dielectric substrate with a dielectric constant of about 20, and a conductor film of about 20 mm square is formed on the surface,
A conductor film is formed on the entire back surface, but grooves are formed on the surface. The conductor film may be formed by printing a thick film of copper or the like, baking it, and then plating it with gold, or the like.

Grooves 15 are formed in parallel with the end surface of the dielectric substrate 10 at the portions corresponding to the end portions of the electrode film on the surface of the dielectric substrate 10.
By forming the groove, the end portion of the electrode film on the surface is also ground. Then, the remaining conductive film forms the radiation electrode 11.

The depth of the groove is arbitrary, but if it is too deep, the strength will be weakened and the effective dielectric constant of the dielectric substrate will be lowered, so that the conductor film can be completely removed. It is desirable to set the depth to the limit. The width shall be such that the conductor film can be removed. If a high precision diamond cutter is used, the groove position can be adjusted with an accuracy of about 5 μm, so it is possible to adjust the resonance frequency of about 2 to 3 MHz in the 1500 MHz band microstrip antenna with the above dimensions. .

It should be noted that it is also possible to form three grooves or less instead of forming four grooves as in the example of FIG. Also, the resonance frequency can be finely adjusted by the depth of the groove.

FIG. 2 shows another embodiment of the present invention (a).
It is a front view and a (b) top view. A 30 mm square dielectric substrate with a dielectric constant of about 20 is formed, and a conductor film is formed on the entire surface.
A conductor film is formed on the entire back surface, but is ground so as to remove a part of the conductor film on the front surface. The conductor film may be a thick film printed with copper or the like, baked, and then plated with gold, or the like, and is formed in a size slightly larger than the desired size.

The surface of the conductor film and the dielectric is ground with the electrode film on the surface of the dielectric substrate 20 from the periphery toward the center. By this grinding, the surface of the dielectric substrate 20 is exposed in the peripheral portion,
The remaining conductive film forms the radiation electrode 11. The conductor film on the back surface becomes the ground electrode 22.

The thickness to be ground is arbitrary, but if it is too deep, the strength will be weakened, and the effective dielectric constant of the dielectric substrate will be lowered, so that the conductor film must be removed to a minimum extent. It is desirable to set the thickness to the limit. The position of the groove can be adjusted with an accuracy of about 5 μm by using a high precision diamond cutter, so it is possible to match the resonance frequency of about 2 to 3 MHz in the 1500 MHz band microstrip antenna with the above dimensions. Becomes In addition, the resonance frequency can be finely adjusted by the thickness to be cut.

[0020]

According to the present invention, a microstrip antenna with good dimensional accuracy can be obtained, and it can be manufactured at low cost.

Further, it becomes easy to finely adjust the dimensions according to variations in materials.

[Brief description of drawings]

FIG. 1A is a front view showing an embodiment of the present invention, and FIG.
Plan view

FIG. 2A is a front view showing another embodiment of the present invention,
(B) Plan view

FIG. 3 is a front view of a conventional microstrip antenna.

[Explanation of symbols]

 10, 20, 30: Dielectric substrate 11, 21, 31: Radiation electrode 12, 22, 32: Ground electrode 15: Groove

[Procedure amendment]

[Submission date] June 26, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction content]

The surface of the conductor film and the dielectric is ground with the electrode film on the surface of the dielectric substrate 20 from the periphery toward the center. By this grinding, the surface of the dielectric substrate 20 is exposed in the peripheral portion,
The remaining conductive film forms the radiation electrode 21 . The conductor film on the back surface becomes the ground electrode 22.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsuyoshi Takano 828 Hinohara, Tamagawa, Hamahara, Hiki-gun, Saitama Prefecture Toko Co., Ltd. Tamagawa factory

Claims (4)

[Claims] 1. A method of manufacturing a microstrip antenna, comprising: a dielectric substrate having a surface on which a radiating electrode having a wavelength of ½ is provided; and a back surface having a ground electrode. And a groove extending parallel to the end face of the dielectric substrate is formed at the end of the electrode film, thereby making the electrode film half the wavelength. Method. 2. A resonance frequency adjusting method for a microstrip antenna, comprising a radiating electrode for ½ wavelength of wavelength on a front surface of a dielectric substrate, and a ground electrode on the entire back surface, in a central portion of the front surface of the dielectric substrate. An electrode film having a size larger than a predetermined size is formed, and a groove extending parallel to the end surface of the dielectric substrate is formed at the end of the electrode film, whereby the size of the electrode film is half the wavelength. And a method for adjusting the resonance frequency of a microstrip antenna. 3. A method for manufacturing a microstrip antenna, comprising a radiation electrode having a wavelength of ½ of the wavelength on the surface of a dielectric substrate and a ground electrode on the entire back surface, wherein an electrode film is formed on the surface of the dielectric substrate. The electrode film is ground from the end surface of the dielectric substrate toward the center to expose the dielectric, and an electrode having a size of ½ of the wavelength is formed in the center of the surface of the dielectric substrate. And a method for manufacturing a microstrip antenna. 4. A resonance frequency adjusting method for a microstrip antenna, comprising a radiating electrode having a wavelength of ½ on the surface of a dielectric substrate and a ground electrode on the entire back surface, wherein an electrode film is provided on the surface of the dielectric substrate. The dielectric film is formed by grinding this electrode film from the end face of the dielectric substrate toward the central part, thereby making the electrode on the surface of the dielectric substrate half the wavelength. Method for adjusting resonance frequency of microstrip antenna.