JPH118894A - Headphone device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a headphone device which can receive signals in good conditions at any position by attaching a prescribed antennas at the outside positions of right and left housing parts and putting together or switching the signals received by each antenna into the received signals of a single system. SOLUTION: The antennas are attached at time outside positions of both housing parts 1L and 1R to receive the audio signals sent from a transmitting device, that is, the monopole antennas 3a and 3b of rod-shaped conductors are attached outside both parts 1L and 1R. In addition, a monopole antenna 3c is directly attached onto the side face of a receiver 6 together with another monopole antenna 3d attached via a signal line 7 that is connected to a jack 6. Thus, four antennas 3a to 3d can be connected together in all. In such a constitution, the signals receive at every high frequency receiving part are supplied to a compositing circuit and part together into the received signals of a single system. Then the decoded audio signals are supplied to both speaker units 2L and 2R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inner-ear type headphone device to be worn on the auricle of a user, and more particularly to a headphone device with a wireless connection to an audio signal source.

[0002]

2. Description of the Related Art Conventionally, a headphone device has various audio signal sources (tape cassette reproducing device, disk reproducing device,
TV receiver, etc.) with a signal line, an audio signal obtained from the audio signal source is supplied to a speaker unit in the headphone device, the audio signal is emitted, and the headphone device is mounted. People were able to hear.

Here, if the headphone device is connected to an audio signal source by a signal line, the signal line is an obstacle for a person wearing the headphone device. Therefore, various types of wireless headphone devices using infrared signals or FM signals have been developed as headphone devices having a configuration in which a signal line between the signal source and the signal source is eliminated.

[0004] By using such a wireless headphone device, the degree of freedom of the wearer of the headphone device is improved as compared with a case where the headphone device is connected by a signal line.

[0005]

By the way, such a wireless headphone device needs to be in a range where a signal from a source of an infrared signal or an FM signal reaches. Especially,
In the case of a wireless headphone device configured to receive an infrared signal, in principle, a transmitting device of an infrared signal in which an audio signal is modulated and an infrared signal receiving unit (light receiving unit) of the wireless headphone device can directly see through. The headphone device needs to be in a state where it cannot be received, and depending on the direction of the headphone device, there is a problem that the state where the headphone device cannot receive the infrared signal and cannot hear audio occurs. In addition, as a headphone device, there is a so-called inner-ear type headphone device that is worn on the auricle of a user. However, this type of headphone device has a small portion exposed from the head when worn, and has an infrared ray. There is a problem that there is no suitable position for arranging the signal receiving section.

In the case of a wireless headphone device configured to receive an FM signal, transmission is possible even when the transmission unit and the reception unit are not directly visible, such as when an infrared signal is used. Even when the distance is short, there is a problem in that interference due to multipath fading occurs and audio cannot be heard.

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to improve the wireless transmission of an audio signal to a headphone device.

[0008]

SUMMARY OF THE INVENTION In order to solve this problem, according to the present invention, when the left and right housing parts are mounted on the auricles, predetermined antennas are attached to positions outside the ear parts, and the antennas of the respective housing parts are used. The received signals are combined or switched to form one system of received signals, and an audio signal included in the received signals is emitted from a speaker unit built in the housing unit.

With this configuration, at least two antennas attached to the housing parts attached to the left and right auricles are arranged so as to face each other in opposite directions. Will have different directivities, for example, by selecting a signal from an antenna that has been successfully received, as long as it is within the range of the signal from the transmission source, it can receive well at any position The likelihood increases.

[0010]

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

FIG. 1 is a diagram showing the overall configuration of a wireless headphone device according to the present embodiment. In this embodiment, the wireless headphone device is an inner-ear type headphone device which is attached to the user's auricle, and an audio signal transmitting device ( (Not shown) to receive an audio signal wirelessly transmitted in a predetermined frequency band,
The sound is emitted from the speaker unit in the headphone device.

In the case of the present embodiment, the housing portions 1L and 1R mounted on the left and right auricles of the user and the receiver 6 for performing the receiving process are provided separately, and the housing portions 1L and 1R include: The small-diameter speaker units 2L and 2R, which are mounted facing the direction of the ear holes, respectively, are built-in.
The left channel audio signal supplied from the speaker unit 2L is emitted from the speaker unit 2L, and the right channel audio signal supplied from the receiver 6 is emitted from the speaker unit 2R.

The left and right housing portions 1L and 1R are connected to the signal line 4
The signal line 5 connects between the left housing part 1L and the receiver 6. A plug 5a having a predetermined shape is attached to the end of the signal line 5, and by attaching the plug 5a to the jack 6a of the receiver 6,
The headphone section is configured to be connected to the receiver.

In the case of this embodiment, an antenna for receiving an audio signal transmitted from the transmitting device is provided outside each of the housing portions 1L and 1R (ie, on the side opposite to the direction in which sound is output toward the ear canal). There is a configuration to attach. Here, monopole antennas 3a and 3b each composed of a single rod-shaped conductor are connected to each of the housing parts 1L and 1L.
It is attached outside R. Here, the transmission band of the audio signal transmitted from the transmitting device is a relatively short wavelength band of several GHz (for example, 2.4 GHz or 5.7 GHz), and the monopole antennas 3a and 3b having a very short length. , And it is possible to receive the signal well.

In this embodiment, the monopole antenna 3c is directly attached to the side of the receiver 6, and another monopole antenna 3d is attached via the signal line 7 connected to the jack 6b. Configuration, total 4
The antennas 3a to 3d are connected.

The receiving circuit in the receiver 6 connected to the plurality of antennas 3a to 3d has, for example, the configuration shown in FIG. Hereinafter, the configuration of FIG. 2 will be described.
Here, each of the antennas 3a, 3b, 3c ‥‥ 3n (n is a value corresponding to the maximum number of connectable antennas) is
Different high-frequency receiving units (RF units) 8 in the receiver 6
a, 8b, 8c ‥‥ 8n, and the antennas 3a, 3
b, 3c} are subjected to reception processing in separate high-frequency receiving sections 8a, 8b, 8c #, respectively. The configuration of each of the high-frequency receiving units 8a, 8b, 8c is, for example, as shown in FIG.
As shown in (1), after the signal supplied from the antenna is amplified by the low noise amplifier 21, the signal is supplied to the mixer 22, where the oscillation output of the oscillator 23 is mixed and frequency-converted into an intermediate frequency signal (or baseband signal). Then, the frequency-converted signal is supplied to an output terminal 25 via a band-pass filter 24 for noise removal, and is supplied from the output terminal 25 to a subsequent circuit.

Returning to the description of the configuration of FIG. 2, the signals received and processed by each of the high-frequency receiving units 8a to 8n are supplied to a synthesizing circuit 9, where a synthesizing process is performed to form one system of received signals. The received signal synthesized by the synthesizing circuit 9 into one system is supplied to a decoder 10, which decodes the received signal by a decoding method applied to the system of the present embodiment, and outputs a left channel analog audio signal and a right channel analog audio signal. Signals are obtained, and the decoded audio signals are supplied to the left and right speaker units 2L and 2R via the signal lines 5 and 4 to emit sound.

The synthesizing process in the synthesizing circuit 9 includes a case where a signal from each antenna is synthesized at a predetermined level and a case where a diversity process for selecting only a signal from an antenna having the best reception state is performed. There is. When performing processing for combining signals from the respective antennas at a predetermined level, for example, the combining processing is performed based on the principle shown in FIG. 4 so that the SN ratio of the received signal is maximized. That is, for example, when combining the received signals x ₁ and x ₂ of the two antennas 81 and 82 is considered, each of the received signals x ₁ and x ₂ is converted into an amplifier 8.
In a configuration in which the signals are amplified by the gains G ₁ and G ₂ at ₃ , 84 and mixed by the mixer 85 to obtain one system of the received signal y at the output terminal 86, the received signal y is expressed by the following equation.

[0019]

[Equation 1] y = G ₁ x ₁ + G ₂ x ₂

Here, the gain G ₁ of the amplifier 83 =
When x ₁ ^* and the gain G _{2 of the} amplifier 84 are set as indicated by G ₂ = x ₂ ^* ( ^* indicates a complex conjugate), the SN ratio of the combined received signal y becomes maximum. The maximum value combining process that satisfies such a condition is performed for all the connected antennas 3.
a, 3b, 3c}, a good received signal can be obtained by the combining process.

When the diversity process is performed, a process of selecting a signal of an antenna having the highest received signal level is performed based on, for example, the principle shown in FIG. That is, as shown in FIG. 5, for example, when a configuration is considered in which the received signals x ₁ and x ₂ of the two antennas 91 and 92 are selected by the switch 93 and one of the received signals is supplied to the output terminal 94. The signal levels of the received signals x ₁ and x ₂ are detected by a level detection circuit 9.
The determination circuit 97 determines which of the level detection circuits 95 and 96 has the higher level, and the switch 93 selects the reception signal on the side determined to have the higher level. , And the received signal y obtained at the output terminal 94. By performing such processing based on the level determination results of the received signals from all the connected antennas 3a, 3b, 3c #, a good received signal can be obtained by the diversity processing.

In the receiver 6 of this embodiment, some kind of battery (dry battery, secondary battery, etc.) or power generation means (solar battery, etc.) is provided, and the above-described reception processing is performed by a power supply supplied from the battery. Then, audio signals are output from the speaker units 2L and 2R. Further, the receiver 6 is provided with a volume control volume 6c and a switch for turning on / off the power (not shown: the volume 6c may be shared).

Here, the connection state between the signal lines and the monopole antennas 3a and 3b attached to the housing portions 1L and 1R will be described. From the receiver 6 to the housing part 1
When a signal line for supplying an audio signal to the speaker units 2L and 2R in the L and 1R is also used as a power supply line to the antenna, the signal line is connected, for example, with the configuration shown in FIG. FIG. 6 is a diagram showing a connection state of the antenna 3a in the left housing portion 1L. The end of the signal line 5 on the housing portion side is connected to a capacitor C ₁ having a predetermined capacitance (for example, about ₁ pF).
Through one end of the monopole antenna 3a.
The end of the signal line 5 on the housing side is connected to the coil L _1.
(For example, about 0.1 μH), and is connected to a terminal 2a for connecting to the speaker unit 2L.
Between the speaker unit 2 and the ground potential terminal 2b.
Connect L.

Further, the housing 6 is provided from the receiver 6 to the housings 1L, 1L.
A signal line for supplying audio signals to the speaker units 2L and 2R in R may be connected to the antennas 3a and 3b using another dedicated signal line. FIG. 7 is a diagram showing an example of a connection configuration in this case. For example, the signal line 5 is a signal line 5x for connecting an antenna and a signal line 5y for connecting a speaker.
Are prepared, and the end of the signal line 5x for connecting the antenna is directly connected to the antenna 3a, and the signal line 5y for connecting the speaker is prepared.
The speaker unit 2L is connected between the terminal 2a at the end and the terminal 2b at the ground potential portion.

According to the thus configured headphone device of the present embodiment, when the inner ear type headphone device mounted on the auricle of the user is mounted, the antenna 3a is provided on a portion exposed to the outside from each housing portion. , 3b, so that the antennas 3a, 3b can satisfactorily receive audio signals wirelessly transmitted from the transmitting device. That is, in a state where the headphone device of the present example is mounted, the two housing portions 1L and 1R are positioned to face each other, and the two antennas 3a and 3b are in a state where the directions are substantially opposite to each other. Each antenna 3a, 3b
Are received with different directivities. By combining or switching the reception signals of the two antennas 3a and 3b, a good reception state can be secured. In particular, in the case of this example, since a signal having a short wavelength of about several GHz is used as a signal to be transmitted, the monopole antennas 3a and 3b having a short length are used.
However, it is possible to receive well, and these two antennas 3
Even if the interval between a and 3b is relatively short, which is equivalent to the interval between the left and right ears of the wearer, there is a high possibility that the reception conditions at the respective antennas 3a and 3b are different. It is highly possible that a good reception state is obtained.

In this embodiment, the antenna 3c is directly connected to the receiver 6 connected to the headphone device, and the antenna 3d is connected to the receiver 6 via the signal line 3d. Accordingly, the received signals of the total of four antennas 3a to 3d can be combined or switched to form one system of received signals, and the reception state can be further improved. Note that the antenna 3c and the antenna 3d on the receiver 6 side may not be provided.

Next, an example in which an antenna having a different configuration is attached to an inner-ear type headphone device will be described below.
FIG. 8 shows an example in which a planar antenna is attached. In this example, the planar antenna 30 is attached to the back surface of the housing portion 1L attached to the user's auricle e, that is, the surface exposed to the outside opposite to the surface from which the sound from the speaker unit 2L is emitted. An example is shown, and a transmission frequency band of an audio signal to be received is, for example, several GH as in the above-described example.
Use a relatively high band on the order of z. FIG. 8 shows only one of the two housing parts 1L and 1R prepared, but the planar antenna 30 is similarly mounted on the other housing part.

The planar antenna 30 has, for example, the configuration shown in FIG. This planar antenna 30 has three substrates 3
A flat antenna and its feed line are configured in a state in which 1, 32, and 33 are overlapped. The size of the three substrates 31, 32, and 33 is, for example, a circular shape corresponding to the size of the back surface of the housing portion 1L. A conductor (such as a copper plate) 3 constituting an antenna element is provided on the surface of the substrate 31 located outside.
1a is formed in a predetermined shape such as a quadrangle, a slit 32a is formed in the center of the central substrate 32, and the substrate 33 located on the inner side has an edge of the substrate 33 from a position corresponding to the slit 32a. Over the strip line 33a
Is provided. Also, the strip line 33a of the substrate 33
A conductor (not shown) such as a copper plate is disposed on the entire back surface opposite to the surface provided with. Stripline 33a at the end portion of the substrate 33 connects a predetermined feed line (e.g., direct connection of the signal line 5x shown in connection or 7 of the signal line 5 through a capacitor C ₁ shown in FIG. 6).

By mounting the planar antenna 30 having such a configuration on the housing portions 1L and 1R constituting the inner-ear type headphone device, it is possible to satisfactorily receive an audio signal transmitted from a predetermined transmitting device. In this case, the conductor 1a constituting the antenna element has a relatively small size in order to be built in the housing portion. However, in the case of this example, a relatively short wavelength band of, for example, about several GHz is used. Sufficient receiving characteristics can be ensured even with a small size. Also, unlike the case of receiving an infrared signal, since the signal can be received even in a situation where the transmission source cannot be directly seen through, it is possible to receive the signal well even when the hair is covered, for example, on a housing portion attached to the auricle. be able to.

In the example shown in FIG. 9, one feeder is connected to one planar antenna to have a polarization plane in one direction. However, feeders in a plurality of directions are connected to one planar antenna. Then, a plurality of polarization planes may be provided. For example, as shown in FIG. 10, a slit 32a is used as a feeder of a planar antenna composed of substrates 31, 32, and 33.
In addition to the strip line 33a through which the signal line 31b is connected from the antenna conductor 31a of the substrate 31 in a direction orthogonal to the strip line 33a,
As a configuration in which power is supplied by 1b, a configuration is adopted in which received signals are individually obtained by the strip line 33a and the signal line 31b. With this configuration, one planar antenna functions as an antenna having two planes of polarization, and the receiving performance is further improved.

When an antenna such as a flat antenna is directly mounted on the housing, an amplifier for amplifying a signal received by the antenna may be mounted near the housing. FIG. 11 is a view showing an example of this case. For example, when the housing 1L to which the planar antenna 30 is attached is attached to the auricle e, the connecting member 41 extends to a position on the back side via the upper side of the auricle e. And a low-noise amplifier housing 42 is connected to the end of the connecting member 41. Then, an element constituting the low noise amplifier is housed in the low noise amplifier housing section 42, and one end of the signal line 5 is connected to the low noise amplifier housing section 42.

FIG. 12 is a diagram showing an example of a connection configuration in this case. The antenna 30 is connected to a low noise amplifier (LNA) 4.
2a, and an amplification output section of the low noise amplifier 42a is connected to an end of the signal line 5 via a capacitor C ₁ (for example, about ₁ pF) having a predetermined capacity. A terminal 2 for connecting the end of the signal line 5 to the speaker unit 2L via a coil L ₁ (for example, about 0.1 μH).
a, and a speaker unit 2L is connected between the terminal 2a and the terminal 2b of the ground potential portion. Further, in order to supply power to the low noise amplifier 42a, the terminal 2a
Between the coils L ₁ and is connected to the power input portion of the amplifier 42a, the power input unit, the capacitor C ₂ of a predetermined capacity
(For example, about 100 pF).

By providing the low-noise amplifier at a position close to the housing in this way, a signal received by the antenna can be efficiently amplified at a position close to the antenna, and more favorable reception characteristics can be secured. In addition, as shown in FIG. 11, by disposing the low-noise amplifier housing at a position behind the auricle, the low-noise amplifier housing is located at a position where it does not interfere with the use of the headphone device. An amplifying element, which is a relatively large element, can be provided in the vicinity of the antenna without deteriorating the wearing feeling of the camera.

Next, an example in which a dipole antenna is attached to the inner-ear type headphone device as an antenna having another configuration will be described with reference to FIGS.

FIG. 13 shows the rear surfaces of the left and right housing portions 1L and 1R mounted on the auricle e of the user, that is, the outer surfaces of the left and right housing portions 1L and 1R, which are exposed on the opposite side to the surface from which sound is emitted from the speaker units 2L and 2R. On the surface, dipole antenna 50L, 50R
Is shown, and the transmission frequency band of the audio signal to be received is, for example, several G as in the above-described example.
A relatively high band of about Hz is used. In this example, the dipole antennas 50L and 50R are attached in a T-shape to the housing portions 1L and 1R, respectively.
It is configured so that it can be rotated at an arbitrary angle around the mounting portion to the R.

FIG. 14 is a view showing a configuration of a mounting portion of the dipole antenna 50L. A member 51 directly connected to the back surface of the housing portion 1L is connected to a center member 53 of the antenna via a rotatable joint 52. One end of the center member 53 is connected to one antenna element 54 and the other antenna element 57. In this case, one of the antenna elements 54 is connected to the conductor portion 54 that penetrates (is rotatable) through the centers of the members 51 and 53, and is connected to the outer conductor of the member 53 by a line 56. A balun structure is formed, and the other antenna element 57 is connected to the outer conductor of the member 53. The length of each of the antenna elements 54 and 57 is λ / 4 (for example, 26 mm).

By using the dipole antenna configured as described above, the dipole antenna is rotated and its position is adjusted in accordance with the reception state at that time, so that the signal can be properly received. And a better reception characteristic can be obtained.

The values of the frequency band and the like described in each of the above embodiments are merely examples, and it is needless to say that signals of other bands may be received. is there.

[0039]

According to the first aspect of the present invention, at least two antennas attached to the housing parts attached to the left and right auricles are arranged in a state where they face in mutually opposite directions. Each antenna has a different directivity.For example, by selecting a signal from an antenna that has been successfully received, as long as it is within the range that the signal from the transmission source can reach, Is more likely to be received.

According to the second aspect of the present invention, since a monopole antenna is used as an antenna disposed in each housing portion, good reception characteristics can be obtained with an antenna having a simple configuration.

According to the third aspect of the present invention, since the dipole antennas rotatably supported with respect to the housing portions are used as the antennas disposed in the respective housing portions, a good reception state is achieved. It becomes possible to adjust the turning position of the dipole antenna,
Better reception characteristics can be obtained.

According to the fourth aspect of the present invention, the use of the planar antennas as the antennas arranged in the respective housing portions enables the reception to be performed well without being protruded from the housing portions.

According to the fifth aspect of the present invention, as a planar antenna, a signal of a plurality of polarization planes is taken out from one antenna, so that one planar antenna functions as a plurality of directional antennas, The receiving characteristics become better.

According to the invention described in claim 6, the amplifying means for amplifying the signal received by the antenna is arranged at a position on the back side of the auricle when the respective housing parts are mounted on the auricle, so that the receiving means is provided. The amplifying means for amplifying the obtained signal fits well in the vicinity of the antenna, and can amplify the received signal well.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an overall configuration of a headphone device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a receiving configuration according to the embodiment of the present invention.

FIG. 3 is a block diagram illustrating an example of an RF unit having the reception configuration illustrated in FIG. 2;

FIG. 4 is a block diagram illustrating a maximum ratio combining process.

FIG. 5 is a block diagram for explaining switching diversity processing.

FIG. 6 is a connection diagram illustrating a connection example of an antenna.

FIG. 7 is a connection diagram showing another example of the connection example of the antenna.

FIG. 8 is a perspective view showing an example in which a planar antenna is attached.

FIG. 9 is a perspective view showing a configuration of a planar antenna.

FIG. 10 is a perspective view showing a configuration when a dual-polarized antenna is used.

FIG. 11 is a perspective view showing an example of a state where a low noise amplifier is attached.

FIG. 12 is a connection diagram illustrating an example of a connection state when a low noise amplifier is provided.

FIG. 13 is a perspective view showing an example in which a dipole antenna is attached.

FIG. 14 is a perspective view showing an example of a mounting portion of a dipole antenna.

[Explanation of symbols]

1L, 1R: housing part, 2L, 2R: speaker unit, 3a, 3b, 3c, 3d: antenna (monopole antenna), 6: receiver, 8a, 8b, 8c: high-frequency receiver (RF part), 9 ... Synthesizing section, 10 ... decoder, 30 ...
Flat antenna, 31a: Antenna element, 32a: Slit, 33a: Slit line, 42: Low-noise amplifier housing, 50L, 50R: Dipole antenna

Claims (6)

[Claims] 1. An antenna disposed at a position outside when two housing parts are mounted on the left and right pinna, when the respective housing parts are mounted on the pinna, and A reception signal processing unit that combines or switches a signal received by an antenna into a single-system reception signal, and a speaker unit that receives an audio signal processed by the reception signal processing unit and is built in each of the housing units. Headphone device provided with. 2. The headphone device according to claim 1, wherein a monopole antenna is used as an antenna provided in each of the housing portions. 3. The headphone device according to claim 1, wherein a dipole antenna rotatably supported with respect to the housing portion is used as an antenna provided in each of the housing portions. 4. The headphone device according to claim 1, wherein a planar antenna is used as an antenna provided in each of the housing portions. 5. The headphone device according to claim 4, wherein the planar antenna is configured to extract signals of a plurality of polarization planes from one antenna. 6. The headphone device according to claim 1, wherein the amplifying means for amplifying the signal received by the antenna is arranged at a position on the back side of the auricle when the respective housing unit is mounted on the auricle. apparatus.