JPH07112130B2 - Left-handed and right-handed circularly polarized antenna device - Google Patents

Description

The present invention relates to a left-handed circularly polarized wave and a right-handed circularly polarized wave of adjacent frequencies that can be simultaneously transmitted or received by one microstrip antenna. And a right-handed circularly polarized antenna device for circularly polarized waves.

(Prior Art) In recent years, a person has possessed a response device or attached to a product,
This response device stores appropriate information of the person who owns it or the product number of the attached product, etc., and the response device that transmits a question signal by microwave from the fixed interrogation device to this response device and receives this interrogation signal A system has been proposed in which an appropriate response signal is transmitted to the interrogation device by microwaves, and the interrogation device compares the received response signal with appropriate means to identify a person or a product. The personal information stored in the response device allows the response device to function as an ID card or the like. Further, by storing information such as the product number and price of the product, inventory management and sales management can be performed.

A communication system including such a response device and an interrogation device is disclosed in JP-A-56-140486 and JP-A-63-54023.
It is disclosed in Japanese Patent Publication No. The outline of the communication system including the response device and the interrogation device shown above will be described with reference to the block circuit diagram of FIG.

In FIG. 4, the interrogation device 1 is provided with an energy transmission circuit 2, and the energy wave f ₁ is transmitted from the antenna 3 to the response device 4 without modulation. Also, the question logic circuit 5
The interrogation signal output from the interrogation logic circuit 5 is transmitted by the interrogation transmission circuit 6 from the antenna 7 to the response device 4 as the interrogation signal wave f ₂ . further,
The interrogation apparatus 1 is provided with an antenna 8 for receiving the response signal wave f ₃ transmitted from the response apparatus 4, and the response reception circuit 9 demodulates the response signal from the response signal wave f ₃ received by the antenna 8 to inquire. It is given to the logic circuit 5. The inquiry logic circuit 5 identifies a person, a product or the like based on a response signal from the response device 4 to the transmitted inquiry signal.

Then, the response unit 4, an antenna 10 for receiving energy wave f ₁ to be transmitted from the antenna 3 is provided, the energy wave f ₁ received by the antenna 10 is converted into DC power by the rectifier circuit 11, in response It is given to the power supply terminal of the logic circuit 12 and used as a drive power supply. Further, an antenna 13 for receiving the interrogation signal wave f ₂ transmitted from the antenna 7 is provided, and the interrogation receiving circuit 14 demodulates the interrogation signal from the interrogation signal wave f ₂ received by the antenna 13 to obtain the response logic circuit 12
Given to. Further, the response signal output from the response logic circuit 12 is given to the response transmission circuit 15, and the antenna 16
Is transmitted from the interrogator 1 as a response signal wave f ₃ . It should be noted that the response logic circuit 12 appropriately calculates according to the inquiry signal based on the stored data and outputs the response signal.

By the way, the energy wave f ₁ transmitted from the interrogation apparatus ₁ is
For example, horizontal polarization of 2440MHz is used, and the interrogation signal wave f
₂ uses vertically polarized waves of 2455 MHz, for example. Since the carrier frequencies of the energy wave f ₁ and the interrogation signal wave f ₂ are adjacent to each other, the division of the energy wave f ₁ and the interrogation signal wave f ₂ is facilitated by making the polarization planes different. A small antenna device is required for transmitting and receiving the energy wave f ₁ and the interrogation signal wave f ₂ . In particular,
When the response device 4 is used as an ID card or the like, it must be small because it is carried by a person. Therefore, a microstrip antenna is used as the antenna device.

Further, in Japanese Patent Laid-Open No. 63-54023, the horizontally polarized energy wave f ₁ and the vertically polarized interrogation signal wave f ₂ are received by one rectangular microstrip resonator as shown in FIG. A technique for reducing the occupied area of the antenna device has been proposed.

In FIG. 5, the length of the horizontal side of the rectangular microstrip resonator 20 is the wavelength λ ₁ of the energy wave f ₁ that is horizontally polarized (the wavelength in the low dielectric substrate on which the microstrip resonator 20 is provided). The following wavelengths are also set to 1/2 of the low dielectric substrate.), And the length of the side in the vertical direction is 1 of the wavelength λ ₂ of the query signal wave f ₂ that is vertically polarized. / 2
Is set to. And a rectangular microstrip resonator
A power supply line 21 for extracting the interrogation signal wave f ₂ is connected to the center of one side of the horizontal direction 20 and a power supply line 22 for extracting the energy wave f ₁ is connected to the center of one side of the vertical direction.

(Problems to be Solved by the Invention) By the way, when the above-described response device 4 is used as an ID card, for example, the person possessed by the question device 1 is identified while the card-shaped response device 4 is stored in a pocket or a handbag. It is extremely convenient if you can. For this purpose, horizontal and vertical polarized waves are used as the energy wave f ₁ and the interrogation signal wave f ₂ , and therefore the antenna device provided in the response device 4 must be in a posture capable of receiving these polarized waves. However, it is actually difficult to manage to store the response device 4 in the pocket or the handbag so that the orientation of the antenna device is one in the vertical and horizontal directions with respect to the polarized wave transmitted from the interrogation device 1. Therefore, it is necessary to take out the response device 4 from the pocket or the handbag and oppose the interrogation device 1 in a certain posture.

In order to eliminate the complexity of the use of the response device 4 as described above, the present inventors have completed the energy wave f ₁ and the interrogation signal wave f ₂
It has been devised that it can be transmitted and received as a circularly polarized wave. With circular polarization, the antenna device can be received regardless of the vertical or horizontal orientation of the antenna device, and it is not necessary to take out the response device 4 from the pocket or the handbag. So the energy wave
If, for example, a left-handed circularly polarized wave of 2440 MHz is used as f ₁ and a right-handed circularly polarized wave of 2455 MHz is used as the interrogating signal wave f ₂ , if these circularly polarized waves can be simultaneously transmitted or received by one microstrip antenna, As in the case shown in the figure, the occupied area of the antenna device can be reduced.

The present invention has been made in view of the above-mentioned circumstances, and is a left-handed and right-handed two-circle polarized light system capable of simultaneously transmitting or receiving left-handed circularly polarized waves and right-handed circularly polarized waves of adjacent frequencies in a small occupied area. It is an object to provide a wave athena device.

(Means for Solving Problems) In order to achieve such an object, there are two types of left-handed and right-handed rotation of the present invention.
The circularly polarized antenna device is an antenna device that simultaneously transmits or receives left-handed and right-handed circularly polarized two circularly polarized waves, and one half of the average value of the wavelengths of the two circularly polarized waves is one side. A square-shaped microstrip resonator and a hybrid link having 1/4 of the average value of the wavelength as one side are provided, and a feed line for left-handed circularly polarized wave and a right-handed ring are provided at two adjacent terminals of this hybrid link. Circularly polarized power supply lines are connected to each other, and the other two terminals of the hybrid link are connected so as to enter the inside of the resonator from the center of two adjacent sides of the microstrip resonator and perform offset power supply. An antenna device for left-handed and right-handed circularly polarized waves, which is configured.

Then, the microstrip resonator is arranged on the front surface of the first low dielectric substrate, and the ground plate is laminated on the rear surface, and the second low dielectric substrate is directly laminated on the ground plate. , The hybrid link and the left-handed and right-handed circularly polarized feed lines are arranged on the second low dielectric substrate,
The microstrip resonator and the terminal of the hybrid link may be electrically connected by a conductive pin penetrating the laminated first and second low dielectric substrates and the ground plate.

Further, the two terminals of the hybrid link may be configured to be in contact with two adjacent sides of the microstrip resonator instead of offset feeding to the microstrip resonator.

(Operation) The signal applied to one terminal of the hybrid link is
90 on two terminals connected to the microstrip resonator
The signals are output as signals whose phases are shifted from each other, and are emitted as circularly polarized waves from the microstrip resonator. Also, the signal applied to the other adjacent terminal of the hybrid link is output as a signal whose phase is shifted by 90 degrees in the opposite direction to the two terminals connected to the microstrip resonator, and the signal is inverted from the microstrip resonator. It is emitted as a circularly polarized wave in the direction of rotation. Moreover, the signal given to one terminal of the hybrid link is not output by canceling each other with the phases reversed at the other adjacent terminal, and the signal isolation between the two is good, Left-handed and right-handed circularly polarized waves can be transmitted simultaneously. Similarly, left-handed and right-handed circularly polarized waves can be simultaneously received and separated and output by the hybrid link.

Then, if the second low-dielectric substrate on which the hybrid link and the left-handed and right-handed circularly polarized power supply lines are arranged is directly laminated on the ground plate, the microstrip resonator and the ground of the hybrid link are arranged. One board can be shared. Moreover, the signal does not leak from the conduction pin due to the waveguide action due to the slight gap that tends to occur when two separate ground plates are superposed.

If the two terminals of the hybrid link are connected to the center of two adjacent sides of the microstrip resonator,
The hybrid link may be coplanar with the microstrip resonator of the first low dielectric substrate.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a plan view showing an array of left-handed and right-handed circularly polarized antenna devices for circularly polarized waves according to an embodiment of the present invention, and FIG. 2 is a view showing a longitudinal section of the substrate of FIG. Is.

In FIGS. 1 and 2, on the surface of the first low dielectric substrate 30, an energy wave f ₁ wavelength λ ₁ transmitted with left-hand circular polarization and an inquiry signal wave f ₂ wavelength transmitted with right-hand circular polarization. of plane value of λ ₂
Square microstrip resonator 31, with one side being 1/2,
Four 31 ... Are arranged at equal intervals. Energy wave
f ₁ and the interrogating signal wave f ₂ are adjacent frequencies. Then, as shown in FIG. 2, a ground plate 32 made of a conductive metal such as aluminum is provided on the back surface of the first low dielectric substrate 30.
And a second dielectric substrate on the ground plate 32.
33 is directly stacked. On the surface of the second low dielectric substrate 32, hybrid links 35, 35 ... And microstrip lines 36, 36 ... As left-handed and right-handed circularly polarized power supply lines are provided. Further, the two terminals of the hybrid links 35, 35 ... And the microstrip resonators 31, 31, ... are formed by stacking the first and second low dielectric substrates 30,
The both ends of the conduction pins 37, 37 ... Penetrating the 33 and the ground plate 32 are connected by soldering.

In addition, the hybrid link 35, 35 ..., the energy wave f ₁
Is formed by a square-shaped box-shaped microstrip line having one side of 1/4 of the average value of the wavelength λ ₁ and the wavelength λ ₂ of the interrogation signal wave f ₂ . Then, the input / output terminal 38 _{a to} which the energy wave f ₁ is applied is first branched into two up to the microstrip line 36 _a as a left-handed circularly polarized power supply line, and the branching strategy is further branched into two, respectively. The four branch destinations are connected to the terminals a, a ... Of the four hybrid links 35, 35 so that the signal waveforms have the same phase. Also,
Output terminal 38 _b of the interrogation signal wave f ₂ is given, it is branched into four in the same manner with the microstrip line 36 _b of the right-handed circularly polarized wave feed line, four hybrid link 3
Are connected to terminals b, b ... Adjacent to the terminals a, a ... of 5,35. Furthermore, the other two terminals c, c ..., d, d ... of the hybrid links 35,35 ...
, So that offset feeding is performed via the conduction pins 37, 37 ... From the center of each of the two adjacent sides of the microstrip resonator 31, 31, ... Inside the resonator by about 1/3 of the length. Connected to.

In such a configuration, input and output terminals 38 energy wave f ₁ given to _a, the hybrid link 35, 35 ... terminal d of, d ... terminal c with respect to the signal, c ... in phase by only 90 degrees delayed It is output as a signal. Therefore, the left-handed circularly polarized wave of the energy wave f ₁ is transmitted from the back side of the paper surface to the front side in FIG. ₁ from the microstrip resonators 31, 31. Then, the signals of the energy wave f ₁ are not output to the terminals b of the hybrid links 35, 35 ... As they are in opposite phase and cancel each other out.

Further, the interrogation signal wave f ₂ given to the input / output terminal 38 _b is connected to the signals at the terminals c, c ... Of the hybrids 35, 35.
Is output as a signal whose phase is delayed by 90 degrees. Therefore, the interrogation signal wave f ₂ right-handed circularly polarized wave is transmitted from the back side of the paper surface to the front side in FIG. 1 from the microstrip resonators 31, 31. And the interrogation signal wave f ₂ is the hybrid link
It is not output to the terminals a of 35, 35 ... Therefore, one antenna device can simultaneously transmit left-handed circularly polarized waves and right-handed circularly polarized waves of adjacent frequencies.

Furthermore, in FIG. 1, the frequency f ₁ from the front to the back of the paper is
When a left-handed circularly polarized wave close to f ₂ comes in, 90 degrees are applied to the terminals d, d… for the signals of the terminals c, c… of the hybrid links 35, 35 connected to the microstrip resonators 31, 31…. phases are delayed signal output, are added in phase at the terminal a, it is outputted to the output terminal 38 _a. The signals at the terminals b cancel each other out of phase. In this way, left-handed circularly polarized waves can be received.

In addition, the frequency f ₁ from front to back on the paper surface of FIG. ₁ or
When a right-handed circularly polarized wave close to f ₂ comes in, 90 is applied to the terminals c, c… for the signals of the terminals d, d… of the hybrid links 35, 35 connected to the microstrip resonators 31, 31. degrees phase being delayed signal output, are added in phase at the terminal b, is output to the output terminal 38 _b. The signals at the terminals a cancel each other out of phase. In this way, right-handed circularly polarized waves can be received. Therefore, a single antenna device can simultaneously receive left-handed circularly polarized waves and right-handed circularly polarized waves having adjacent frequencies.

By the way, in the above embodiment, the second low dielectric substrate 33 is disposed directly on the ground plate 32, and the microstrip resonator 3
Since one ground plate 32 is commonly used for the 1, 31, ... And the hybrid links 35, 35, etc., there is no signal attenuation by the conduction pin 37.

By the way, it is also possible to use a second low-dielectric substrate 33 provided with its own ground plate and to stack two ground plates to form a laminated structure. However, when the two ground plates are configured to be stacked,
A slight gap is likely to occur between the two ground plates. Then, this gap acts as a waveguide, the signal radiated from the conduction pin 37 leaks through this gap, and the signal applied to the microstrip resonators 31, 31 ... Is attenuated. Therefore, as in the above embodiment, the first low dielectric substrate
It is desirable that the second low dielectric substrate 33 be directly laminated on the ground plate 32 laminated on 30.

FIG. 3 is a plan view of the essential parts showing another embodiment of the left-handed and right-handed circularly polarized antenna device for circularly polarized waves of the present invention. In FIG. 3, the same members as those in FIG. 1 are designated by the same reference numerals, and duplicate description will be omitted.

In FIG. 3, the microstrip resonator 31 and the hybrid link 35 are arranged on the same plane of the low dielectric substrate. The microstrip line 36 _a as a left-handed circularly polarized wave feed line is connected to the terminal a of the hybrid link 35, the microstrip line 36 _b of the right-handed circularly polarized wave feed line to the terminal b of the hybrid link 35 Connected. Furthermore, the terminal d of the hybrid link 35 is connected via a microstrip line 39 _a to the central portion of one side of the microstrip resonator 31. Also, terminal c
But is connected via a microstrip line 39 _b in the central portion of one side of the terminal d of the microstrip resonator 31 is adjacent clockwise to the connected edges.

Even with such a configuration, as in the embodiment shown in FIG.
Microstrip line as a feeder for left-handed circularly polarized waves
The energy wave f ₁ given to 36 _a is transmitted as a left-handed circularly polarized wave, and the interrogation signal wave f ₂ given to the microstrip line 36 _b as the feed line for the other right-handed circularly polarized wave is a right-handed circularly polarized wave. Transmitted as circularly polarized wave. Then, formed in the same step of so microstrip resonator 31 and the hybrid link 35 and the microstrip line _{36 a, 36 b, 39 a} , 39 b can be disposed on the same plane of the lower dielectric substrate, such as etching and deposition And can be manufactured easily.

In the above example, the left-hand circularly polarized wave of 2440MHz and 2455MHz
Although the antenna device for right-handed circularly polarized wave was described as an example, it is not limited to the above frequency, and it is configured to transmit and receive left-handed and right-handed circularly polarized waves of adjacent frequencies that lie in the microwave band. Is also good. The left-handed and right-handed circularly polarized antenna devices for circularly polarized waves according to the present invention are not limited to the application to the antenna device of the communication system including the interrogation device 1 and the response device 4.

(Effects of the Invention) The left-handed and right-handed circularly polarized antenna device for dual-circular polarization of the present invention is configured as described above, and therefore exhibits the following excellent effects.

First, one antenna device can simultaneously transmit or receive left-handed and right-handed two-circular polarized waves of adjacent frequencies, and the area occupied by the antenna device is small. Easy to miniaturize. Since circularly polarized waves are transmitted / received, proper transmission / reception is possible regardless of the orientation of the antenna device in the vertical and horizontal directions. Further, the transmitted and received left-handed and right-handed circularly polarized signals of two circularly polarized waves are well isolated, and the two power supply lines do not leak to each other.

If the second low dielectric substrate on which the hybrid link is arranged is directly laminated on the ground plate, one ground plate can be shared and it is inexpensive. Moreover, there is no signal leakage due to the conduction pins that penetrate the plurality of stacked substrates.

If the two terminals of the hybrid link are connected to the centers of the two adjacent sides of the microstrip resonator, the hybrid link and the microstrip resonator can be arranged on the same plane of the low dielectric substrate. ,
It can be manufactured in the same process, and the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a plan view showing an array of left-handed and right-handed circularly polarized antenna devices for circularly polarized waves according to an embodiment of the present invention, and FIG. 2 is a view showing a longitudinal section of the substrate of FIG. And FIG. 3 shows
FIG. 4 is a plan view of an essential part of another embodiment of a left-handed and right-handed circularly polarized antenna device for circularly polarized waves according to the present invention. FIG. FIG. 5 is a block circuit diagram showing an outline of a communication system including a response device and an inquiry device suitable for application, and FIG. 5 is a diagram showing an example of a conventional antenna device applied to the communication system of FIG. . 30: first low dielectric substrate, 31: microstrip resonator, 32: ground plate, 33: second low dielectric substrate, 35: hybrid link, 36, 39: microstrip line, 38: input / output terminal .

Front page continued (72) Inventor Yoshikazu Kawashima 1-12-2 Kawana, Fujisawa-shi, Kanagawa Yamatake Honeywell Co., Ltd. Fujisawa Plant (72) Hiroaki Furushima 1-22 Kawana, Fujisawa, Kanagawa Yamatake Honeywell Co., Ltd. Fujisawa factory (56) Reference JP-A-57-188107 (JP, A) JP-A-63-23403 (JP, A) JP-A-63-174413 (JP, A) JP-A-63-69301 (JP , A) Actual development Sho 62-51809 (JP, U)

Claims (3)

[Claims] 1. An antenna device for simultaneously transmitting or receiving left-handed circularly polarized waves and right-handed circularly polarized waves of adjacent frequencies, which is a square having one side of 1/2 of the average value of the wavelengths of the two circularly polarized waves. A microstrip resonator and a hybrid link whose one side is 1/4 of the average value of the wavelength are provided, and the adjoining two terminals of this hybrid link have a left-hand circular polarization feed line and a right-hand circular polarization feed line. A feed line is connected to each of the two, and the other two terminals of the hybrid link are connected so as to enter the inside of the resonator from the center of two adjacent sides of the microstrip resonator and perform offset power supply. A left-handed and right-handed circularly polarized antenna device for circularly polarized waves. 2. The left-handed and right-handed circularly polarized antenna device according to claim 1, wherein the microstrip resonator is disposed on the front surface of the first low dielectric substrate and a ground plate is laminated on the rear surface. The second low dielectric substrate is directly laminated on the ground plate, and the hybrid link and the left-handed and right-handed circularly polarized power supply lines are provided on the second low-dielectric substrate. Then, the microstrip resonator and the terminal of the hybrid link are electrically connected by a conduction pin penetrating the laminated first and second low dielectric substrates and the ground plate. A circular antenna device for circularly polarized waves. 3. The left-handed and right-handed circularly polarized antenna device according to claim 1, wherein the two terminals of the hybrid link are offset-fed to the microstrip resonator instead of the microstrip resonator. A left-handed and right-handed circularly polarized antenna device for dual-circular polarization, which is connected to the center of two adjacent sides of a resonator.