JP2004205578A - Audio reproducing equipment communicating audio signal by radio and method of controlling power consumption of audio reproducing equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an audio reproducing equipment, which can be reduced in power consumption while maintaining excellent usability and uses a connection type radio communication system like the Bluetooth system, and a power consumption control method. <P>SOLUTION: In an operation method in a power-saving mode implemented by a Bluetooth-audio converting adapter 20, the power-saving mode is a process of setting a Bluetooth module 30 of the Bluetooth-audio converting adapter 20 in a Sniff mode or a Park mode (in which a communication link of Bluetooth is maintained) and entering a power-saving state. Here, the Sniff mode is a process mode in which up to seven Bluetooth devices (slaves) can be set in the power-saving mode while connections are maintained and the Park mode, on the other hand, is a process mode which can be set to the power-saving mode while connections with eight or more Bluetooth devices are maintained. In an embodiment of the present invention, a case of entering the Sniff mode as the power-saving mode as the power-saving mode is explained. Further, the power-saving mode is a process of disconnecting Bluetooth links to completely stop the Bluetooth module 30 from operating. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an audio playback device that wirelessly communicates an audio signal to a wireless headphone device or the like, and particularly to a power consumption control method for power saving of the device.
[0002]
[Prior art]
Conventionally, communication connection between electronic information communication devices is generally performed by a wired method, but recently, an attempt has been made to improve usability by applying a wireless method instead.
[0003]
Also, with the advent of personal area wireless technologies such as Bluetooth and HomeRF, adoption of these wireless interfaces has been studied for electronic information communication devices such as personal computers and mobile phones, and practical use has begun. Furthermore, application to various fields is expected in the future, and application to AV devices such as music playback devices is also expected to be great.
[0004]
One of the applications to this AV equipment is AV data transmission to wireless headphones. In this case, connecting the wireless headphones to the audio player eliminates the need for a conventional connection cable, and a more comfortable audio playback environment is expected. Conventionally, in the field of wireless headphones, those using infrared rays, high-frequency radios, and the like have been put to practical use. However, such a conventional wireless headphone has a problem in that it is not always easy to use because of a problem of directivity and a shield.
[0005]
Therefore, in recent years, wireless headphones using Bluetooth technology have been developed (see Patent Document 1).
[0006]
[Patent Document 1]
JP-A-2002-112383
[0007]
[Problems to be solved by the invention]
In the case of a sound reproducing device that transmits data such as sound to wireless headphones using infrared rays or the like, when there is no sound signal input, the power of the transmitting device is automatically turned off and there is no sound signal input. In such a case, a method of saving power by turning on the power is used.
[0008]
However, in the case of a connection-type wireless communication system such as Bluetooth, since various data are transmitted and received while maintaining a logical connection, application to many devices is attempted. In order to maintain the above condition, the transmission / reception operation must be performed even during a period in which audio data or the like is not transmitted, so that a large amount of power is constantly consumed. In such a situation, there is a problem that the remaining battery level of the apparatus is significantly reduced.
Therefore, when a connection-type wireless communication system such as Bluetooth is applied to a portable device or the like, the problem of power saving control must be solved in order to enable long-time driving.
[0009]
In the present invention, in order to solve the above-described problems, a sound reproducing device and a power consumption device using a connection-type wireless communication system such as a Bluetooth system capable of realizing a reduction in power consumption while maintaining good usability. It is an object to provide a control method.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, in the audio reproducing apparatus of the present invention, an audio input means for inputting an audio signal, and a conversion means for converting the audio signal input by the audio input means into a wireless communication signal capable of wireless communication Wireless communication means for transmitting the wireless communication signal converted by the conversion means to an external device which has established a communication link, detection means for detecting the level of the audio signal input by the voice input means, and detection means Power-saving means for reducing the power consumption of the wireless communication means in a state in which the communication link of the wireless communication means is established when detecting that the input level of the audio signal from the audio input means is equal to or lower than the predetermined level during the first predetermined period. First setting means for setting the mode, and after setting the wireless communication means to the power saving mode by the first setting means, the detecting means sets the voice input means for a second predetermined period. And a second setting unit that disconnects a communication link of the wireless communication unit and stops the operation of the wireless communication unit when detecting that the input level of the audio signal is equal to or lower than a predetermined level. Is what you do.
Further, in the power consumption control method of the audio reproducing apparatus according to the present invention, the audio signal input from the audio input means is converted into a wireless communication signal capable of wireless communication, and the converted wireless communication signal is used to establish a communication link. The level of the audio signal input by the audio input means is detected by the wireless communication means, and as a result of this detection, the input level of the audio signal from the audio input means is detected for the first predetermined period. After detecting that the level is equal to or lower than the predetermined level, the wireless communication unit is set to the power saving mode for reducing power consumption while the communication link of the wireless communication unit is established, and the wireless communication unit is set to the power saving mode. Further, when the input level of the audio signal from the audio input means is detected to be lower than the predetermined level for a second predetermined period, the communication link of the wireless communication means is disconnected and the wireless communication means is disconnected. It is characterized in that the operation stop state.
[0011]
With the above configuration, when the audio signal is at a certain level or less (silent state), the wireless communication unit is automatically shifted to the power saving mode, and further, the operation of the wireless communication unit is stopped to reduce power consumption. Can be achieved.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0013]
FIG. 1 shows a system configuration using a music playback device and wireless headphones according to an embodiment of the present invention.
[0014]
In FIG. 1, a portable audio player 10 reproduces music data stored in a music data storage medium (MD, memory card, hard disk, or the like) and outputs it as an analog audio signal from a headphone terminal. As a general usage, a normal headphone of a wired system can be connected to the headphone terminal to listen to music. In one embodiment of the present invention, an audio signal is transmitted to the Bluetooth wireless headphone 12. It is possible to listen to music by wireless transmission.
[0015]
The Bluetooth wireless headphone 12 has wireless communication means of a Bluetooth system, and performs wireless communication according to a system determined by the Bluetooth standard. The Bluetooth standard defines an AV profile standard for wirelessly transmitting and receiving HiFi audio data, and can receive and play music data wirelessly communicated by Bluetooth in accordance with the AV profile. .
[0016]
The wireless headphone 12 is provided with an antenna 14 for transmitting and receiving audio data and the like and an operation unit 16. The operation unit 16 is provided with operation buttons necessary for various operations, such as a power (on / off) button and a reproduction processing button.
[0017]
Further, the system is provided with a Bluetooth-audio conversion adapter 20 which can be connected to the headphone terminal 18 of the portable player 10. The conversion adapter 20 has an input terminal for an analog audio signal that can be connected to the headphone terminal 18, and a signal input from this input terminal is converted into a PCM signal by an AD converter. Further, the PCM signal is compressed by a compression method (such as SBC = Sub Band Coding) determined by the AV profile standard, and the audio data is transmitted to the wireless headphones 12 by a communication method and a communication protocol conforming to the AV profile. It is.
[0018]
The Bluetooth-audio conversion adapter 20 includes an antenna 22 for performing Bluetooth communication, an LCD 24 for transmitting various information to the user, and operation buttons (power button, audio data transmission Etc.) 26 are provided.
[0019]
In one embodiment of the present invention, the portable audio player 10 and the Bluetooth-audio conversion adapter 20 constitute an audio reproducing device for wirelessly communicating audio data according to one embodiment of the present invention.
[0020]
Next, the hardware configuration of the Bluetooth-audio conversion adapter 20 will be described with reference to FIG.
[0021]
The Bluetooth-audio conversion adapter 20 includes an antenna 22, a Bluetooth module 30, an MPU (Micro Processing Unit) 32, a ROM 34, a RAM 36, and an EEPROM 38.
[0022]
The antenna 22 is of the 2.4 GHz band for performing Bluetooth communication. The Bluetooth module 30 is for performing Bluetooth communication, has a built-in RF circuit and a Baseband control circuit for performing Bluetooth communication, and shifts to various Bluetooth modes based on an instruction from the MPU 32. is there. The MPU 32 operates according to the program code stored in the ROM 34 and controls the entire apparatus.
[0023]
The adapter 20 includes a ROM 34, a RAM 36, and an EEPROM 38 as memories. The ROM 34 is a read-only memory in which a program for operating the MPU 32 is stored. The RAM 36 functions as a writable / readable memory used as various work memories by the MPU 32, and the EEPROM 38 is a rewritable nonvolatile memory for storing address information of a connection destination under the control of the MPU 32. It functions as.
[0024]
Further, the Bluetooth-audio conversion adapter 20 includes a DSP (Digital Signal Processor) 40 for compressing and encoding audio data based on an instruction from the MPU 32, and operation information when a user operates the operation button 26. A button control circuit 42 for transmitting to the MPU 32, an LCD control circuit 44 for displaying various information such as an operation state of the apparatus on the LCD 24 based on the control of the MPU 32, an LED 46 for transmitting the state of the apparatus to the user based on the lighting state, and various kinds of LEDs A timer 48 for measuring operation time and the like is provided.
[0025]
Further, the adapter 20 is provided with an input level detection circuit 50, an AD converter 52, an input level adjustment circuit 54, and an analog audio input terminal 56.
[0026]
The input level detection circuit 50 detects whether or not the input signal level from the analog audio input terminal 56 to which the analog audio data is input is higher than a predetermined value, and transmits the detection result to the MPU 32. The AD converter 52 converts the analog audio data input from the analog audio input terminal 56 into digital data, and inputs the digital data to the DSP 40. The input level adjustment circuit 54 is provided to adjust the input level of the AD converter 52 based on the control from the MPU 32.
[0027]
Further, the Bluetooth-audio conversion adapter 20 is provided with a power supply control circuit 58 for controlling a power supply for driving the adapter 20, based on a control from the MPU 32 or a signal from the input level detection circuit 50. The power supplied to the conversion adapter 20 is controlled. Further, the conversion adapter 20 is provided with a rechargeable secondary battery 60 and an AC adapter 62 for charging the secondary battery 60.
[0028]
A specific operation method of the Bluetooth-audio conversion adapter 20 configured as described above will be described.
[0029]
First, a connection between the Bluetooth-audio conversion adapter 20 and the Bluetooth wireless headset 12 and a method of transmitting audio data from the conversion adapter 20 to the headphones 12 will be described with reference to a flowchart shown in FIG.
(1) Connection between Bluetooth-audio conversion adapter 20 and Bluetooth wireless headphones 12
The Bluetooth-audio conversion adapter 20 and the Bluetooth wireless headphones 12 are paired in advance.
[0030]
That is, the conversion adapter 20 stores in the EEPROM 38 the BD address of the wireless headphone 12 to be connected and the authentication code (link key) at the time of connection. Similarly, on the Bluetooth wireless headphone 12 side, the BD address and the authentication code (link key) of the Bluetooth-audio conversion adapter 20 to be connected are stored, whereby the conversion adapter 20 and the headphone 12 are pair-linked. You.
[0031]
In such a state, when the operation button of the conversion adapter 20 is pressed by the user to instruct the start of the operation, the Bluetooth module 30 is set to the operation permission state (STEP 10).
[0032]
In the Bluetooth-audio conversion adapter 20, the Bluetooth module 30 searches (Inquiry) for a connectable Bluetooth device, and when a Bluetooth device having a BD address registered in the EEPROM 38 is found, a Bluetooth connection with the device is made ( (STEP 12).
(2) Transmission of audio data
In the Bluetooth-audio conversion adapter 20, the level of the analog audio input from the analog audio input terminal 56 is adjusted to an appropriate analog signal level by the input level adjustment circuit 54, and then converted to a PCM signal by the AD converter 52 (STEP 14). .
[0033]
The audio data converted into the PCM signal is encoded by the DSP 40 in the SBC format (STEP 16).
[0034]
The encoded SBC data is wirelessly transmitted to the Bluetooth wireless headphones 12 via the Bluetooth module 30 and the antenna 22 as an AV profile (STEP 18).
[0035]
Next, an operation method of the power saving mode executed by the Bluetooth-audio conversion adapter 20 according to one embodiment of the present invention will be described with reference to the flowcharts of FIGS.
[0036]
First, with reference to the flowchart of FIG. 4, a description will be given of a process of shifting to the power saving mode 1 and the power saving mode 2 and a process of returning from the power saving mode 1.
[0037]
Here, the power saving mode 1 is a process of setting the Bluetooth module 30 of the Bluetooth-audio conversion adapter 20 to the Sniff mode or the Park mode (a state in which the Bluetooth communication link is maintained) and shifting to the power saving state. Here, the Sniff mode is a processing mode in which the number of Bluetooth devices (slaves) that can be set to the power saving mode while maintaining the connection is up to seven, and the Park mode is a connection mode in which eight or more Bluetooth devices are connected. This is a processing mode that can be set to the power saving mode while maintaining (synchronization). In one embodiment of the present invention, a case will be described as an example in which a transition is made to the Sniff mode as the power saving mode.
The power saving mode 2 is a process of disconnecting the Bluetooth link and completely stopping the operation of the Bluetooth module 30.
(3) Shift to power saving mode 1
According to the Bluetooth standard, when actual data communication is not performed, a power saving mode (Sniff mode or Park mode) that reduces power consumption of the Bluetooth module 30 by transmitting and receiving only a signal for maintaining a Bluetooth link at predetermined time intervals. ) Is specified.
[0038]
Specifically, when the MPU 32 instructs the Bluetooth module 30 to shift to the Sniff mode, the Bluetooth module 30 receives this instruction, performs necessary negotiations with the connection partner by air communication, and completes the negotiation. Then, the Bluetooth module 30 shifts to the Sniff mode.
[0039]
In the Sniff mode, at regular intervals (for example, 10 seconds), it becomes Active only for a fixed time (for example, 0.5 seconds), performs Air communication, and performs information necessary for maintaining the Bluetooth connection (information for maintaining timing and synchronization). Etc.). In addition, the Bluetooth module 30 is in an operation stop state during a period in which no action is performed, thereby reducing power consumption. In this case, since the link state is maintained, it is possible to quickly return from the power saving mode to the normal data communication mode.
[0040]
In the Bluetooth-audio conversion adapter 20, when a Bluetooth connection is made with the wireless headphone 12 (STEP 20), the timer 48 is operated to count the operation time (STEP 22), the audio signal is encoded by the DSP 40, and the AV profile is converted to the headphone. 12 (STEP 24).
[0041]
At this time, in the conversion adapter 20, the input level detection circuit 50 monitors whether the signal level of the analog signal input from the audio analog input terminal 56 is equal to or higher than a predetermined value (STEP 26).
[0042]
When the input level detection circuit 50 detects that the signal level of the analog signal is equal to or higher than a certain level (the analog signal is not in a silent state), the timer 48 is always initialized to “0”. (STEP 14), transmission of the AV signal (STEP 24), and detection of the analog signal level by the input level detection circuit 50 (STEP 26) are continued.
[0043]
When the input level detection circuit 50 detects that the signal level of the analog signal has fallen below a certain level (that is, when it is determined that the analog signal is silent), the timer 48 is initialized. The count is incremented and continues until the value of the timer 48 reaches a predetermined time count value T1 (about 5 to 10 seconds) (STEP 28).
[0044]
Next, when the timer 48 counts up to the time count value T1 (that is, when it is determined that the state determined to be a silent state has continued for the time count T1), the Bluetooth-audio conversion adapter 20 switches the Bluetooth module 30 The mode is set to the Sniff mode and the state is shifted to the power saving state (STEP 28). Further, in this state, the clock of the MPU 32 is lowered, the operation of the DSP 40 is stopped, and the MPU 32 and the DSP 40 are shifted to the power saving state (STEP 32).
[0045]
As described above, in the audio reproduction device according to the embodiment of the present invention, when the silent state continues for a certain period of time (about 3 to 5 seconds), the power is automatically shifted to the power saving state to reduce the power consumption. be able to.
(4) Shift to power saving mode 2
After the Bluetooth-audio conversion adapter 20 shifts to the power saving mode 1, if the state determined to be the silent state continues for the time count T2 (about 2 to 5 minutes) (STEP 34 to STEP 38), the conversion is performed. The adapter 20 shifts to the power saving mode 2 which consumes less power than the power saving mode 1 (however, it takes a longer time to return to the normal state than the power saving mode 1).
[0046]
When the mode shifts to the power saving mode 2, the Bluetooth link is disconnected (STEP 40), and the operation of the Bluetooth module 30 is completely stopped (STEP 42). Further, the operation of the MPU 32 is completely stopped (STEP 44). In this state, some circuits such as the input level detection circuit 50 and the timer 48 are operable, but the power consumption is almost zero.
[0047]
That is, in the audio reproducing device according to the embodiment of the present invention, when the silent state continues for a certain period of time (about 2 to 5 minutes) or more, the power consumption can be further reduced compared to the power saving mode 1. By automatically shifting to the power mode 2, it is possible to further enhance the power saving effect.
(5) Return from power saving mode 1
When the input level detection circuit 50 detects that analog audio that is not in a silent state is input from the analog audio input terminal 56 while the Bluetooth-audio conversion adapter 20 is in the power saving mode 1 (Park state), the conversion is performed. In the adapter 20, the MPU 32 and the DSP 40 are activated (STEP 46), the Park state of the Bluetooth module 30 is released, and the data communication is enabled (STEP 48).
[0048]
At this time, since there is a slight delay from the detection of the audio signal to the start of the transmission of the audio data, when returning from the power saving mode 1, the audio signal immediately after the detection of the audio signal is not transmitted. Therefore, in the audio reproduction by the Bluetooth wireless headphone 12, the first short portion of the audio signal is not reproduced, and is started from the middle.
[0049]
Therefore, in order to reduce discomfort caused by sudden start of audio reproduction, the conversion adapter 20 first sets the volume level to the lowest level when the DSP 40 encodes the audio signal when transmission is resumed (STEP 50). In this state, the transmission of the audio data according to the AV profile is restarted by the Bluetooth module 30 (STEP 52). Next, the volume level at the time of encoding in the DSP 40 is gradually increased to the normal volume level, and control for transmitting the AV profile to the wireless headphones 12 is performed (STEP 54).
[0050]
By performing the above-described control, the audio reproduction device of the embodiment of the present invention automatically transmits audio data even when the audio input is resumed even in the power saving mode. Transmission can be resumed, and the usability of the user can be greatly improved.
[0051]
Furthermore, when the transmission of audio data is resumed, the volume level of the audio data to be transmitted is set to a low volume state, and the processing is gradually increased until the audio level reaches the normal level. Thus, it is possible to reduce the user's discomfort caused by the start of the sound reproduction from.
[0052]
Next, the return process from the power saving mode 2 will be described with reference to the flowchart of FIG.
(6) Return from power saving mode 2
When the input level detection circuit 50 detects that an analog voice that is not in a silent state is input while the Bluetooth-audio conversion adapter 20 is in the power saving mode 2 (STEP 60), the conversion adapter 20 starts the MPU 32. (Wakeup) (STEP 62), and the operation of the Bluetooth module 30 is permitted (STEP 64).
[0053]
Next, the BT module 30 searches (Inquiry) for a connectable Bluetooth device (STEP 66). When a Bluetooth device having a BD address registered in the EEPROM 38 is searched (STEP 68), the Bluetooth connection with the device is performed. Is performed (STEP 70).
[0054]
In this case, when the connection with the Bluetooth device is completed, in order to eliminate the discomfort given to the user of the Bluetooth wireless headphone 12, the DSP 40 performs the same operation as when returning from the power saving mode 1 shown in the flowchart of FIG. When encoding the audio signal, first, the volume level is set to the lowest level (STEP 50). In this state, the transmission of the audio data according to the AV profile is restarted by the Bluetooth module 30 (STEP 52). The volume level at the time of encoding is gradually increased to the normal volume level, and a process of transmitting the AV profile to the wireless headphones 12 is executed (STEP 54).
[0055]
If a connectable Bluetooth device cannot be found during the inquiry, the conversion adapter 20 stops the operation of the Bluetooth module 30 (STEP 72), and further stops the clock of the MPU 32 (STEP 74). The mode shifts to the power saving mode 2.
[0056]
In this state, after a predetermined count time T3 (about 2-5 minutes) has elapsed by the timer 48, the presence or absence of a voice input is detected by the input level detection circuit 50, and there is a voice input (not a silent state). Is detected, the process of returning from the power saving mode 2 is executed again in the same manner as described above, and connection with the Bluetooth device is attempted (STEP 76, STEP 60, 62, 64, 66).
[0057]
In the Bluetooth-audio conversion adapter 20, when an audio input signal of a certain level or more is detected in an operation stop state, (1) the Bluetooth module 30 and the MPU 32 are set in an operation permission state, and (2) a device to be wirelessly connected. (3) If a connectable device is found, a wireless communication link is established with the device and transmission of audio data is started.
[0058]
With these processes, even if the state is shifted to the power saving mode 2, when the voice input is restarted, the restart is detected, and the Bluetooth connection is automatically established without user operation. Transmission of audio data can be resumed.
[0059]
In addition, in the Bluetooth-audio conversion adapter 20, even when the voice input is resumed, if no device to be wirelessly connected is found, the operation of the Bluetooth 30 and the MPU 32 is stopped, and after a predetermined time has elapsed, the Bluetooth-audio conversion adapter 20 is again set to a certain level. When a voice input of a level or more is made, a process of searching for a partner to be wirelessly connected is executed to enhance the power saving effect.
[0060]
Next, a connection processing method according to the second embodiment of the present invention will be described with reference to the flowchart shown in FIG.
[0061]
In the above-described embodiment, an example has been described in which a connection is established with a device to which a connection partner is set in advance (already paired), but a device searched as a Bluetooth device instead of a paired device is described. It is also conceivable that a connection is made with the device, and a connection processing method in that case will be described.
[0062]
In this case, first, when performing initial connection or reconnection after disconnection, it is first searched whether a paired device can be found (STEP 100). As a result, if a device that has been paired in advance can be found, Bluetooth connection processing with the found device is executed (STEPs 102 and 104), and the connection process is completed.
[0063]
If no paired device is found as a result of the search, all Bluetooth devices having the same Bluetooth profile (AV profile) are searched (STEPs 102 and 106).
[0064]
As a result of this search, if the Bluetooth device cannot be established, the Bluetooth-audio conversion adapter 20 shifts to the power saving mode (STEPs 108, 110, 112). Specifically, similarly to the transition to the power saving mode 2, the operation of the Bluetooth module 30 is stopped (STEP 110), and further the clock of the MPU 32 is stopped (STEP 112). In this state, after a predetermined count time T3 (approximately 2-5 minutes) has elapsed by the timer 48 (STEP 114), the input level detection circuit 50 detects the presence or absence of a voice input, and based on the detection status of this voice input. To retry the Bluetooth connection.
[0065]
If a Bluetooth device is found as a result of the search, the Bluetooth-audio conversion adapter 20 requests connection with those devices in the order in which the devices were found (STEP 116), and a connection permission signal is sent from the partner Bluetooth device requesting the connection. When the connection is received, the connection with the connection-permitted device is executed, and the connection process is completed (STEPs 118 and 120).
[0066]
As a result of sequentially requesting connection to the searched Bluetooth devices, if connection is not permitted from all Bluetooth devices, the devices are set to the low current consumption mode, and the operation of the Bluetooth module 30 is stopped (STEP 110). Further, the clock of the MPU 112 is stopped (STEP 112), and after a lapse of a certain period of time, the connection with the Bluetooth device is tried again.
[0067]
In this embodiment, when trying to connect to a Bluetooth device that has not been paired, when a search for a connectable Bluetooth device has failed, and connection to the Bluetooth device has not been established, transition to the power saving mode is performed. Power consumption can be reduced. Furthermore, in this embodiment, a search for a connectable Bluetooth device and retry of the connection process are performed after a predetermined time has elapsed, so that a user-friendly device can be provided to the user.
[0068]
As described above, in the embodiment of the present invention, in the audio reproduction device that transmits the audio signal using the Bluetooth method, if there is no input of the audio signal for a predetermined period, or the Bluetooth device to be connected is searched for. When it is not possible, by automatically shifting to the power saving mode, power consumption can be reduced and power saving can be achieved.
[0069]
Further, even in the transition to the power saving mode, the audio reproducing device according to the embodiment of the present invention automatically performs the process of returning from the power saving mode when detecting the input of the audio signal. In addition, even if a Bluetooth device to be connected is not found, power can be saved without impairing user convenience by automatically retrying the search process for a Bluetooth device to be connected after a predetermined time has elapsed. Is provided.
[0070]
In the above-described embodiment, an example has been described in which a connection is established with a device whose connection partner is set in advance (already paired), but a device searched as a Bluetooth device instead of a paired device is described. It is also conceivable that a connection is made with the device, and a connection processing method in that case will be described.
[0071]
It should be noted that the present invention is not limited to the above-described embodiment, and can be implemented with various modifications within the scope of the gist.
[0072]
For example, in the above-described embodiment, the Bluetooth-audio conversion adapter 20 has been described as an example of a configuration including the analog audio input terminal 56. However, in order to enable input of a digital audio signal, a configuration including a digital audio input interface circuit is provided. It may be.
[0073]
Further, in the above embodiment, the Bluetooth-audio conversion adapter 20 is shown as an example of the configuration of an external adapter completely independent of the portable audio player 10, but the conversion adapter 20 is provided inside the audio player 10 and integrated therewith. It is also possible to apply to a device connected inside the player.
[0074]
【The invention's effect】
As described in detail above, according to the present invention, it is possible to reduce power consumption while maintaining good usability in an audio playback device using the Bluetooth system.
[Brief description of the drawings]
FIG. 1 is a diagram showing a system configuration using a music playback device and wireless headphones according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration example of a Bluetooth-audio conversion adapter illustrated in FIG. 1;
FIG. 3 is a flowchart showing a processing procedure of a method of transmitting audio data between the music reproducing device and the wireless headphones shown in FIG. 1;
FIG. 4 is a flowchart for explaining a processing procedure of a transition process to a power saving mode and a return process from the power saving mode of the audio reproduction device shown in FIG. 1;
FIG. 5 is a flowchart illustrating a processing procedure of a return process from a power saving mode of the music playback device illustrated in FIG. 1;
6 is a flowchart showing a processing procedure when the music playback device shown in FIG. 1 connects to a searched Bluetooth device.
[Explanation of symbols]
10… Portable audio player
12… Bluetooth wireless headphones
20… Bluetooth-audio conversion adapter
30… Bluetooth module
32… MPU
40 ... DSP
48… Timer
50 ... input level detection circuit
56… Analog audio input terminal

Claims (13)

Voice input means for inputting a voice signal;
Conversion means for converting the audio signal input by the audio input means into a wireless communication signal capable of wireless communication,
A wireless communication unit that transmits the wireless communication signal converted by the conversion unit to an external device that has established a communication link;
Detecting means for detecting the level of an audio signal input by the audio input means,
When the detection means detects that the input level of the audio signal from the audio input means is equal to or lower than a predetermined level for a first predetermined period, the wireless communication means is connected to the wireless communication means in a state where the communication link is established. First setting means for setting a power saving mode for reducing power consumption;
After the wireless communication unit is set to the power saving mode by the first setting unit, the input level of the audio signal from the audio input unit is lower than the predetermined level by the detection unit for a second predetermined period. And a second setting unit that disconnects a communication link of the wireless communication unit and stops the operation of the wireless communication unit when the communication unit detects the fact. In a state where the wireless communication unit is set to the power saving mode by the first setting unit, when the detection unit detects an audio signal of a predetermined level or more, the setting of the power saving mode of the wireless communication unit is performed. 2. The audio reproducing apparatus according to claim 1, further comprising means for canceling the transmission of the audio signal and restarting the transmission of the audio signal. When the wireless communication means is set to the operation stop state by the second setting means, and when the detection means detects an audio signal of a predetermined level or higher, the operation of the wireless communication means is permitted, and 2. The audio reproducing apparatus according to claim 1, further comprising means for searching for an external apparatus for establishing a link and restarting transmission of the audio signal. Voice input means for inputting a voice signal;
Conversion means for converting the audio signal input by the audio input means into a wireless communication signal capable of wireless communication,
A wireless communication unit that transmits the wireless communication signal converted by the conversion unit to an external device that has established a communication link,
Detecting means for detecting the level of an audio signal input by the audio input means,
When the detection unit detects that the input level of the audio signal from the audio input unit is equal to or lower than a predetermined level for a predetermined period, the power consumption of the radio communication unit is reduced in a state where the communication link of the radio communication unit is established. Setting means for setting the power saving mode to be reduced;
An audio playback device comprising: In a state where the wireless communication unit is set to the power saving mode by the setting unit, when the detection unit detects an audio signal of a predetermined level or higher, the wireless communication unit cancels the setting of the power saving mode and releases the audio. 5. The audio reproducing apparatus according to claim 4, further comprising means for restarting signal transmission. When the transmission of the audio signal from the wireless communication unit is restarted, the apparatus further includes a volume adjustment unit that sets the volume level of the audio signal wirelessly transmitted from the wireless communication unit to gradually increase. The audio reproducing device according to claim 2 or 5, wherein It further comprises an audio input terminal for inputting an audio signal corresponding to the music data from an audio player for reproducing the music data, and an antenna for wirelessly communicating the audio signal from the wireless communication means to a wireless device. The audio reproduction device according to claim 1. The audio signal input from the audio input means is converted into a wireless communication signal capable of wireless communication,
In a power consumption control method of an audio reproduction device that transmits the converted wireless communication signal to an external device that has established a communication link by wireless communication means,
Detecting the level of the audio signal input by the audio input means,
As a result of this detection, when it is detected that the input level of the audio signal from the audio input means is equal to or lower than a predetermined level for a first predetermined period, the wireless communication means is connected to the wireless communication means while the communication link is established. Set to power saving mode to reduce power consumption,
After the wireless communication unit is set to the power saving mode, when the input level of the audio signal from the audio input unit is detected to be equal to or lower than the predetermined level for a second predetermined period, the communication link of the wireless communication unit is changed. A method for controlling power consumption of an audio reproducing device, comprising disconnecting the wireless communication unit to stop the operation. The audio signal input from the audio input means is converted into a wireless communication signal capable of wireless communication,
In a power consumption control method of an audio reproduction device that transmits the converted wireless communication signal to an external device that has established a communication link by wireless communication means,
Detecting the level of the audio signal input by the audio input means,
As a result of this detection, when it is detected that the input level of the audio signal from the audio input means is equal to or lower than a predetermined level for a predetermined period, the power consumption of the wireless communication means is reduced in a state where the communication link of the wireless communication means is established. A power consumption control method for an audio playback device, characterized by setting a power saving mode to reduce power consumption. When detecting an audio signal of a predetermined level or more in a state where the wireless communication unit is set to the power saving mode, canceling the setting of the power saving mode of the wireless communication unit and restarting transmission of the audio signal. The power consumption control method for an audio reproduction device according to claim 8 or 9, wherein: When the wireless communication unit is set to the operation stop state, and when the detection unit detects an audio signal of a predetermined level or more, the operation of the wireless communication unit is permitted, and an external device for establishing a communication link is searched. 9. The method according to claim 8, wherein the transmission of the audio signal is resumed. 12. The apparatus according to claim 10, wherein when the transmission of the audio signal from the wireless communication unit is restarted, the volume level of the audio signal wirelessly transmitted from the wireless communication unit is set to be gradually increased. Power control method for audio playback equipment. The audio signal input from the audio input means is converted into a wireless communication signal capable of wireless communication,
In a power consumption control method of an audio reproduction device that transmits the converted wireless communication signal to an external device that has established a communication link by wireless communication means,
Search for external devices to establish a communication link,
As a result of the search, when the external device that establishes the communication link cannot be searched, the wireless communication unit is set to an operation stop state,
After a lapse of a predetermined time when the operation of the wireless communication unit is stopped, when an input of an audio signal from the audio input unit is detected, an external device for establishing a communication link is searched again. Power consumption control method for equipment.

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