JPH1070601A - Hand-free equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hand-free equipment in which a loss of a variable loss circuit is switched corresponding to an analog/digital operation of a mobile equipment. SOLUTION: Two kinds of losses for analog/digital quantity are prepared in advance for a transmission variable loss circuit 3 and a reception variable loss circuit 7, loss selection circuits 11, 12 receive analog/digital operation identification information outputted from a mobile equipment 5 and when the analog operation is identified, insertion of the smaller analog loss to the transmission variable loss circuit 3 and the reception variable loss circuit 7, and when the digital operation is identified, insertion of the larger digital loss to the transmission variable loss circuit 3 and the reception variable loss circuit 7 are instructed respectively so that a speech with simultaneous communication is attained when the mobile equipment is in analog operation and a speech with excellent speech quality resulting from a delayed voice signal generated from the mobile equipment is eliminated when the mobile equipment is in digital operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a hands-free device used by connecting to a mobile device having a function capable of supporting both an analog system and a digital system.

[0002]

2. Description of the Related Art Conventionally, regardless of whether a mobile device operates in an analog system or a digital system, a hands-free device connected to the mobile device is used in an analog system. When the mobile device operates in a digital system, the transmission signal from the hands-free device needs to be A / D converted, and the reception signal to the hands-free device needs to be D / A converted.

[0003] During the A / D and D / A conversion processing in this mobile device, a delay of the audio signal occurs, which causes acoustic echo during hands-free communication.

FIG. 2 is a block diagram showing a main configuration of a conventional hands-free device. The transmission voice input to the microphone 1 is input to the mobile device 5 via the amplifier 2, the variable loss circuit 3, and the amplifier 4, and is transmitted to the telephone network.

On the other hand, the received voice transmitted from the telephone network is output from the speaker 9 through the amplifier 6, the variable loss circuit 7 and the amplifier 8 from the mobile device 5.

[0006] The switching control circuit 10 compares the transmitted voice signal input from the microphone 1 with the received voice signal from the mobile device 5, and when the transmitted voice signal is larger than the received voice signal, the switching control circuit 10 changes the variable loss circuit. 3 is set not to be inserted, and the loss of the variable loss circuit 7 is set to be inserted. That is, the transmission voice is transmitted to the telephone network at a predetermined level, and the reception voice level output from the speaker 9 is reduced by the loss inserted in the variable loss circuit 7.

When the received voice signal is larger than the transmitted voice signal, the loss of the variable loss circuit 3 is set to be inserted, and the loss of the variable loss circuit 7 is set not to be inserted. That is, the transmission voice is transmitted to the telephone network with the transmission level lowered by the loss amount inserted in the variable loss circuit 3, and is output from the speaker 9 at a predetermined reception voice level.

As described above, in the conventional hands-free device, regardless of whether the mobile device operates in the analog system or the digital system, the loss amount of the variable loss circuit is fixed at the same set amount. Prioritized either one of the callability. In other words, if the amount of loss is set to be small so as to be suitable for the analog system, simultaneous conversation can be performed in the analog system, but the loss is too small in the digital system / audio signal generated during the D / D / A conversion processing. Acoustic echo is heard due to the delay, and the call quality is degraded.

If the amount of loss is set large so as to be suitable for the digital system, acoustic echo is canceled out in the digital system, and a call with good call quality can be performed. I will.

[0010]

In the conventional hands-free device, the loss amount of the variable loss circuit is fixed at the same set amount regardless of whether the mobile device operates in an analog system or a digital system. When priority is placed on the callability, the call quality is degraded.

That is, if the amount of loss is set to be small so as to correspond to the analog system, when the mobile device operates in the digital system, the acoustic echo generated by the delay of the voice signal generated by the mobile device will cause an acoustic echo of the call. This hinders the call quality.

[0012] When priority is given to the speech quality, the simultaneous speech performance is degraded.

[0013] That is, if a large amount of loss is set to correspond to the digital system, when the mobile device operates in the analog system, the acoustic echo can be sufficiently canceled, but the simultaneous talkability deteriorates.

[0014] An object of the present invention is to provide a simultaneous communication capability in an analog system and a communication quality in a digital system by setting an optimal loss amount for each system when the mobile device operates in an analog system or a digital system. It is to provide a good hands-free device.

[0015]

A hands-free device according to the present invention compares a transmitted voice signal and a received voice signal to be connected to a mobile device that operates by switching between an analog system and a digital system. When the speaking voice signal is large, the transmitting mode is determined, and when the receiving voice signal is large, the receiving mode is determined. When the transmitting mode is set, the insertion loss of the transmitting path is removed, and a predetermined loss is inserted into the receiving path. A hands-free device that inserts a predetermined loss into the transmission path and eliminates insertion loss in the reception path at the time of: in response to the analog operation or digital operation of the mobile station, the transmission path or the reception path The loss amount to be inserted is switched.

Also, the transmission voice signal and the reception voice signal to be connected to a mobile device which operates by switching between the analog system and the digital system are compared, and when the transmission voice signal is large, the transmission mode, the reception voice When the signal is large, the mode is determined to be the receiving mode, and when the mode is the transmitting mode, the insertion loss of the transmitting channel is removed.
A hands-free device that inserts a predetermined loss into a reception path, inserts a predetermined loss into a transmission path when in a reception mode, and eliminates insertion loss in the reception path; There is provided means for identifying, and the loss amount to be inserted into the transmission path or the reception path is switched based on the identification result.

Further, the transmission voice signal and the reception voice signal to be connected to a mobile device that operates by switching between the analog system and the digital system are compared, and when the transmission voice signal is large, the transmission mode, the reception voice When the signal is large, the mode is determined to be the receiving mode, and when the mode is the transmitting mode, the insertion loss of the transmitting channel is removed.
A hands-free device that inserts a predetermined loss into a receiving channel, inserts a predetermined loss into a transmitting channel in a receiving mode, and eliminates insertion loss in a receiving channel; A transmission path loss insertion / removal means and a reception path loss insertion / removal means comprising: a loss amount; receiving analog / digital operation state information from the mobile device, identifying whether the mobile device is in analog operation or digital operation; Insertion loss selecting means for instructing the transmission path loss insertion / removal means and the reception path loss insertion / removal means to insert the analog loss amount or the digital loss amount; comparing the transmitted voice signal with the received voice signal; Loss amount insertion / removal instructing means for judging the transmission mode or the reception mode, and instructing the transmission path loss insertion / removal means and the reception path loss insertion / removal means to instruct whether or not the loss amount can be inserted; Upon receiving the loss amount insertion enable / disable instruction from the loss amount insertion / removal instruction means and the analog / digital loss amount insertion instruction from the insertion loss selection means, the analog loss amount or the digital loss amount is inserted / removed. The transmission path loss insertion / removal means and the reception path loss insertion / removal means.

Therefore, by setting the amount of insertion loss for analog to a small value in consideration of simultaneous callability, excellent call performance can be ensured, and the amount of insertion loss for digital can be reduced by the amount of voice signal generated by a mobile unit. By setting a large value in consideration of the delay, the acoustic echo can be removed.

[0019]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a main configuration of a hands-free device of the present invention. The hands-free device shown in FIG. 1 includes a microphone 1 that collects a speaker's voice and outputs a transmission voice signal, an amplifier 2 that amplifies a transmission voice signal output by the microphone 1 to a predetermined level, a predetermined loss A variable loss circuit 3 for inserting and withdrawing the amount, and amplifying a transmission voice signal passing through the variable loss circuit 3 to a predetermined level and
, An amplifier 6 that receives the received voice signal from the mobile device and amplifies the received voice signal to a predetermined level, a variable loss circuit 7 that inserts and removes a predetermined loss amount, and a received voice signal that has passed through the variable loss circuit 7. An amplifier 8 for driving the speaker 9 by amplifying it to the level of
The level of the transmission voice signal amplified by the amplifier 2 and the reception voice signal amplified by the amplifier 6 are compared, and the variable loss circuits 3 and
Switching control circuit 10 for reciprocally controlling the insertion / removal of the loss amount
And control switches 11 and 12 for setting the loss amount of the variable loss circuits 3 and 7 for analog or digital depending on whether the analog / digital mobile device is operating in analog or digital mode.

Next, the operation will be described with reference to FIG.

The switching control circuit 10 compares the level of the transmitted voice signal amplified by the amplifier 2 to a predetermined level with the level of the received voice signal amplified by the amplifier 6 to a predetermined level. Determines the transmission mode, prohibits insertion of the loss amount into the variable loss circuit 3, and permits insertion of the loss amount into the variable loss circuit 7.

On the other hand, when the received voice signal is large, it is determined that the receiving mode is set, and the variable loss circuit 3 is permitted to insert the loss amount, and the variable loss circuit 7 is prohibited from inserting the loss amount.

Therefore, in the transmission mode, the transmission voice signal is amplified to a predetermined level by the amplifier 2 and
Then, the signal passes through without being attenuated, is amplified to a predetermined level by the amplifier 4, and is transmitted at a predetermined transmission level via the mobile device 5. At this time, the received voice signal is attenuated by the loss amount inserted into the variable loss circuit 7, and is amplified through a speaker.

In the receiving mode, the received voice signal is amplified to a predetermined level by the amplifier 6 and passed through without being attenuated by the variable loss circuit 7, amplified to a predetermined level by the amplifier 8, and amplified by the speaker 9. It is louder. At this time, the transmission voice signal is attenuated by the loss inserted into the variable loss circuit 3 and transmitted to the telephone network via the mobile device 5.

In the variable loss circuits 3 and 7, two kinds of loss amounts for analog and digital are set, respectively. The mobile device 5 outputs an operation identification signal indicating whether it operates in an analog system or a digital system to the hands-free device. The insertion loss selection circuits 11 and 12 are controlled by the operation identification signal. Insertion loss selection circuits 11 and 12
Controls the variable loss circuits 3 and 7 to insert an analog loss amount when the operation identification signal indicates that the mobile device 5 operates in an analog system. Therefore, the variable loss circuit 3,
Since a small loss amount is set in 7, a call with simultaneous callability is possible.

When the operation identification signal indicates that the mobile device 5 is operating in a digital system, the insertion loss selection circuit 11,
Reference numeral 12 controls the variable loss circuits 3 and 7 so as to insert a digital loss amount. Accordingly, since a large loss is set in the variable loss circuits 3 and 7, an acoustic echo caused by the delay of the voice signal generated in the mobile device 5 can be removed, and a call with good call quality can be made.

As described above, by providing two types of loss amounts in the variable loss circuits 3 and 7 and switching them in accordance with the analog / digital operation of the mobile device, the communication performance suitable for the analog / digital operation of the mobile device is improved. Obtainable.

[0028]

As described above, according to the present invention, in a hands-free device connected to a mobile device operating in both an analog system and a digital system, a transmission path corresponding to the analog operation and digital operation of the mobile device is provided. Two types of loss amounts, one for analog and one for digital, are prepared to be inserted into the variable loss circuit and the reception path variable loss circuit, and operation identification information for distinguishing between analog operation and digital operation output from the mobile device is received. When analog operation is indicated, a small loss amount for analog is inserted, and when operation identification information indicates digital operation, a large loss amount for digital is inserted into the transmission path variable loss circuit and the reception path variable loss circuit. In addition, since the loss amount inserted into the transmission path variable loss circuit and the reception path variable loss circuit are reciprocally inserted and removed, the mobile device operates in a digital system. Enables better call the call quality without acoustic echo in the case, it is possible call with simultaneous calls property when the mobile station is operating in a digital manner.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a main configuration of a hands-free device of the present invention.

FIG. 2 is a block diagram showing a main configuration of a conventional hands-free device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 microphone 2 amplifier 3 transmission path variable loss circuit 4 amplifier 5 mobile unit 6 amplifier 7 reception path variable loss circuit 8 amplifier 9 speaker 10 switching control circuit 11, 12 insertion loss selection circuit

Claims (3)

[Claims] 1. A transmission voice signal and a reception voice signal which are connected to a mobile device which operates by switching between an analog system and a digital system are compared. When the signal is large, it is determined to be in the receiving mode, and in the transmitting mode, the insertion loss of the transmitting channel is removed, and a predetermined loss is inserted in the receiving channel, and in the receiving mode, a predetermined loss is inserted in the transmitting channel. A hands-free device for removing insertion loss of a receiving path; switching a loss amount inserted into the transmitting path or the receiving path in response to an analog operation or a digital operation of the mobile device. Free equipment. 2. A transmission voice signal and a reception voice signal, which are connected to a mobile device that operates by switching between an analog system and a digital system, are compared. When the signal is large, it is determined to be in the receiving mode, and in the transmitting mode, the insertion loss of the transmitting channel is removed, and a predetermined loss is inserted in the receiving channel, and in the receiving mode, a predetermined loss is inserted in the transmitting channel. And a hands-free device for eliminating insertion loss of a receiving path;
A hands-free device, comprising: means for identifying a digital operation state, wherein a loss amount inserted into the transmission path or the reception path is switched based on the identification result. 3. A transmission voice signal and a reception voice signal, which are connected to a mobile device that operates by switching between an analog system and a digital system, are compared. When the signal is large, it is determined that the receiving mode is set, and in the transmitting mode, the insertion loss of the transmitting channel is removed, and a predetermined loss is inserted in the receiving channel, and in the receiving mode, a predetermined loss is inserted in the transmitting channel. And a hands-free device for removing insertion loss of a reception path; a transmission path loss insertion / removal means and a reception path loss insertion / removal means provided with a predetermined analog loss amount and a digital loss amount; Receiving the analog / digital operation state information, discriminating whether the mobile station is in analog operation or digital operation, and transmitting the analog loss amount or the data to the transmission path loss insertion / removal means and the reception path loss insertion / removal means; Insertion loss selecting means for instructing insertion of a digital loss amount; comparing a transmission voice signal with a reception voice signal to determine the transmission mode or the reception mode; the transmission path loss insertion / removal means; Loss amount insertion / removal instruction means for reciprocally instructing loss insertion / rejection of the loss amount to the loss insertion / removal means; loss amount insertion / rejection instruction from the loss amount insertion / removal instruction means and insertion loss selection means The transmission path loss insertion / removal means and the reception path loss insertion / removal means for inserting / removing the analog loss amount or the digital loss amount upon receiving the analog / digital loss amount insertion instruction. And hands-free device.