JPH08102617A - Antenna system - Google Patents

Abstract

PURPOSE: To improve antenna efficiency and a selectivity characteristics and to eliminate the necessity of a shared device for a radio unit. CONSTITUTION: An antenna 13 completely matched with transmitting frequency and an antenna 14 completely matched with receiving frequency are formed on a film 15 or a substrate as a built-in antenna 12 in a mobile station 11 and respective antennas are mutually connected through inductance elements 20, 21 for tuning a transmitting circuit 19 and a receiving circuit 18 in a radio unit 17, so that a transmitting radio wave can be efficiently transmitted and a receiving radio wave can be efficiently received, a speaking distance can be improved, the radiation of unnecessary frequency components other than the transmitting radio wave and the reception of unnecessary radio waves from the external can be suppressed, and the selectivity characteristics can be also improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device connected to a wireless device having a transmitting and receiving function such as a cordless telephone or a mobile telephone.

[0002]

2. Description of the Related Art Conventionally, an antenna of a cordless telephone device is a single antenna, uses a dual-frequency resonant antenna that resonates at a transmission frequency and a reception frequency, and in consideration of design, it may be configured with a built-in antenna. It is commonplace. FIG. 4 shows the configuration of a dual-frequency resonance type built-in antenna. In FIG. 4, 1 is a mobile station of a cordless telephone device, 2 is a built-in antenna, 3 is an antenna, 4a and 4b are coils, 5 is an LC parallel resonant element, 6 is a conducting wire, 7 is a wireless unit, 8 is a duplexer, and 9 is a duplexer. Is a receiving circuit, and 10 is a transmitting circuit.

Next, the operation of the above conventional example will be described.
The two-frequency resonance type built-in antenna 2 is provided with coils 4a, 4b and an LC parallel resonance element 5 in the middle of the antenna 3,
The antenna from the tip to the LC parallel resonant element 5 is used as a high-frequency receiving antenna, and the antenna 3 including the LC parallel resonant element 5 is used as a low-frequency receiving antenna. In addition, the wireless unit 7 side has a built-in antenna 2
The received signals are transmitted by the transmission circuit 10 because
In order to prevent the transmission signal from leaking to the receiving circuit 9, the receiving circuit 9 and the transmitting circuit 10 are connected to the built-in antenna 2 and the conducting wire 6 through the duplexer 8.

As described above, the mobile station 1 of the conventional cordless telephone device can transmit the transmission frequency and receive the reception frequency by the duplexer 8 and the dual-frequency resonance type built-in antenna 2. There is.

[0005]

However, since the above-mentioned conventional antenna device is a dual-frequency resonance type antenna, matching is sufficiently performed as compared with the case where dedicated antennas for transmission and reception are used. However, there is a problem in that the antenna efficiency is poor, the selectivity characteristic is weak, and the radiation of unnecessary frequency components and the external unnecessary frequency are easily affected. In addition, the wireless unit connected to the antenna also requires a duplexer, which saves space on the board, costs, and
There was a problem that the performance deteriorates due to the loss during insertion.

[0006] The present invention solves such a conventional problem, and an object of the present invention is to provide an antenna device which has good antenna efficiency and selectivity and does not require a duplexer.

[0007]

In order to achieve the above object, the present invention provides a linear conductor having a length resonating at a transmission frequency and a linear conductor having a length resonating at a reception frequency.
One antenna is formed on one film or substrate, the transmitting side antenna is connected to the transmitting circuit of the wireless unit, and the receiving side antenna is connected to the receiving circuit of the wireless unit.

[0008]

Therefore, according to the present invention, since the transmitting side antenna which is perfectly matched to the transmitting frequency band is connected to the transmitting circuit, the transmitting radio wave is efficiently radiated from the antenna and unnecessary components other than the transmitting frequency are unnecessary. The transmission of radio waves in the frequency band can be suppressed, and the receiving side antenna, which is perfectly matched to the reception frequency band, is connected to the reception circuit, so that the reception radio waves can be received efficiently and unnecessary signals other than the reception frequency Reception of radio waves can be suppressed, antenna efficiency and selectivity characteristics are improved, and a duplexer is not required.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of the first embodiment of the present invention. In FIG. 1, 11 is a mobile station of a cordless telephone device, 12 is a built-in antenna, 13 is a zigzag-shaped antenna for tuning to a transmission frequency, and 14 is a zigzag-shaped for tuning to a reception frequency. Antenna, 15 is a film provided with each antenna 13, 14
Is a wireless unit, 18 is a receiving circuit, 19 is a transmitting circuit, 2
Reference numeral 0 is an inductance element for tuning the antenna 13 on the transmission side to the transmission frequency, and 21 is an inductance element for tuning the antenna 14 on the reception side to the reception frequency. The antenna 13 for tuning to the transmission frequency is a film 15
It is formed of a copper pattern on the top and has a wavelength of 1
The length is close to / 4, and the antenna 14 for tuning to the reception frequency is also formed by a copper pattern on the same film 15 and has a length close to 1/4 of the wavelength of the reception frequency.
It is formed as a single antenna. Antenna 1 for transmission
3 is connected to a radio unit 17 by a conductor 16 and is connected to a transmitter circuit 19 through an inductance element 20 for precisely tuning the antenna 13 to the transmission frequency.
The receiving antenna 14 is connected to the wireless unit 17 by a conductor 16 and is connected to the receiving circuit 18 through an inductance element 21 for accurately tuning the antenna 14 to the receiving frequency.

Next, the operation of the above embodiment will be described.
In the case of transmission, the transmission wave transmitted from the transmission circuit 19 is
Since the antenna 13 is tuned exactly to the transmission frequency,
Electric power is effectively transmitted to the antenna 13, and the electric field strength of the transmitted wave can be improved. In the case of reception, since the antenna 14 is accurately tuned to the reception frequency, radio waves can be effectively received and can be transmitted to the reception circuit 18 without attenuation.
Therefore, the transmission performance and the reception performance can be improved, and the call distance can be improved. Further, by having the antennas 13 and 14 dedicated to transmission and reception, the selectivity on the antenna can be improved. That is, unnecessary frequencies other than the transmission wave generated from the transmission circuit 19 are attenuated by the antenna 13 itself to suppress the transmission of unnecessary frequency components, and the reception antenna 14 can receive the reception frequency even when radio waves other than the reception frequency are present. It is also possible to suppress the occurrence of sensitivity suppression and the like by selecting and receiving only.

FIG. 2 shows the overall configuration of the mobile station in the above embodiment. In FIG. 2, 11 is a mobile station of a cordless telephone device, 12 is a built-in antenna, 17 is a wireless unit, 22 is a receiver, and 23 is a control board having a numeric keypad and the like. Since the built-in antenna 12 is provided on the uppermost part of the mobile station 11 as shown in the drawing, the radio performance is ensured to the maximum, and the human body is less likely to be affected when the mobile station 11 is held by hand. It is possible to obtain stable characteristics.

FIG. 3 shows the configuration of the second embodiment of the present invention. In FIG. 3, 31 is a mobile station of a cordless telephone device, 32 is a built-in antenna, 33 is a spiral antenna for tuning to a transmission frequency, and 34 is a zigzag shape for tuning to a reception frequency. An aerial line, 35 is a substrate provided with the respective aerial lines 33 and 34, and 36 is each aerial line end portion 33 extended to a support leg 35a of the substrate 35.
a, a radio unit, 37 is a receiving circuit, 39 is a transmitting circuit, 40 is an inductance element for tuning the antenna 33 on the transmitting side to the transmission frequency, and 41 is the receiving side. An inductance element for tuning the antenna 34 of the transmitter to the reception frequency, and 42 is the transmitter circuit 3
9 is a copper pattern for supplying transmission power to the antenna 33 through the inductance element 40, and 43 is the antenna 34.
A copper pattern for supplying the electric power received from the electric circuit to the receiving circuit 38 through the inductance element 41, 44 is a screw hole formed between the ends 42a and 43a of the copper patterns 42 and 43, and 45 is a mounting screw. .

Next, the operation of the above embodiment will be described.
The antenna 33 for tuning to the transmission frequency is formed of a copper pattern on the substrate 35 and has a wavelength of 1/1 of the transmission frequency.
The antenna 34 for tuning to the reception frequency is also formed on the same substrate 35 with a copper pattern and has a length close to ¼ of the wavelength of the reception frequency, and is formed as one antenna. ing. The ends 33a and 34a of the antennas 33 and 34 are formed in a semicircular shape so as to have a diameter larger than the diameter of the screw head of the mounting screw 45, and the ends of the copper patterns 42 and 43 of the wireless unit 37. 42a and 43a are also formed in the same size as the antenna end portions 33a and 34a, so that the screw insertion hole 36 of the support leg 35a of the board 35 is aligned with the screw hole 44 of the wireless unit 37 and the mounting screw 45 is fastened. Thus, the antenna 33 can be connected only to the copper pattern 42 on the transmitting side, and the antenna 34 can be connected only to the copper pattern 43 on the receiving side (the antennas 33 and 34 are formed on the back side of the substrate 35). .).

As described above, according to the second embodiment,
In addition to the effects of the first embodiment, the two antennas 33 and 34 can be connected to the corresponding transmitting circuit 39 and receiving circuit 38 with only one mounting screw 45.

[0015]

As is apparent from the above embodiment, the present invention has an antenna precisely tuned to the transmission frequency and an antenna precisely tuned to the reception frequency, so that the antenna efficiency and selectivity characteristics are good. The transmission electric field strength and the reception sensitivity can be improved, the communication distance can be extended, and the suppression of sensitivity due to unnecessary radiation and external radio waves can be suppressed. Further, since the antenna is configured only by the copper pattern without the LC circuit, it is possible to significantly reduce the cost. Further, since the wireless unit does not require a duplexer, it is possible to reduce the space and cost of the board and prevent performance deterioration.

[Brief description of drawings]

FIG. 1 is a partial configuration diagram of a mobile station provided with an antenna device showing a first embodiment of the present invention.

FIG. 2 is an overall configuration diagram of a mobile station according to the first embodiment of the present invention.

FIG. 3 is a partial configuration diagram of a mobile station provided with an antenna device showing a second embodiment of the present invention.

FIG. 4 is a partial configuration diagram of a mobile station including a conventional antenna device.

[Explanation of symbols]

 11 mobile station 12 built-in antenna 13 antenna on the transmitting side 14 antenna on the receiving side 15 film 16 conducting wire 17 wireless unit 18 receiving circuit 19 transmitting circuit 20 inductance element 21 inductance element 22 receiver 23 control board 31 mobile station 32 built-in antenna 33 transmitting side Antenna 34 Antenna on receiving side 35 Board 36 Screw insertion hole 37 Radio unit 38 Reception circuit 39 Transmission circuit 40 Inductance element 41 Inductance element 42 Copper pattern 43 Copper pattern 44 Screw hole 45 Mounting screw

Claims (3)

[Claims] 1. A linear conductor having a length that resonates at a transmission frequency and a linear conductor having a length that resonates at a reception frequency.
An antenna device in which two antennas are formed on one film or a substrate, the transmitting side antenna is connected to the transmitting circuit of the wireless unit, and the receiving side antenna is connected to the receiving circuit of the wireless unit. 2. The antenna device according to claim 1, wherein two antennas are provided at the top of the wireless device. 3. An antenna connection part on the transmission side and an antenna connection part on the reception side of the wireless unit are formed so as to face the ends of the two antennas, and the respective antenna ends are brought into contact with the respective antenna connections. The antenna device according to claim 1, wherein the antenna device is screwed.