KR20000026077A - Hands free car audio device - Google Patents

Abstract

PURPOSE: A hands free car audio device is provided to add a hands free function simply and cheaply, to reduce a conventional howling and echo phenomena, and to increase communication quality. CONSTITUTION: A hands free car audio device includes an audio circuit unit(106), a mobile phone call code connection unit(102), a mike(104), an audio processing unit(108), a switching unit(110), a power amplifying unit(112), speakers(FL, FR), a power unit(114), and a control unit(116). The audio circuit unit outputs an audio signal played from at least one of audio sources to a stereo signal. The mike is implemented in front of a driver seat in the car, and picks up a driver's voice. The audio processing unit receives a received voice signal of the mobile phone through the call code connection unit, selects a first stereo input of the driver's voice through the mike and at least one of second stereo input of stereo audio signal applied to the audio circuit unit. The switching unit switches selectively one output corresponding to the mike of the audio processing unit between a first speaker and the mike output terminal of the call code connection unit. The power amplifying unit inputs and amplifies the speaker output of the switching unit and another output of the audio processing unit. A pair of the speakers output a voice by output of the power amplifying unit. The power unit generates an operating voltage of each unit, a mobile phone battery voltage to the call code, and a mobile phone operating voltage. The control unit is connected to the mobile phone via the call code connection unit, controls charging of the battery in the hands free mode, controls the audio processing unit to select the first stereo input and the switching unit to select the call code connection unit in the communication mode, outputs a received voice signal through one of the pair of the speaker, applies the voice signal picked up in the mike to the mobile phone.

Description

Handsfree car audio device

The present invention relates to a hands-free car audio device, and more particularly, to a hands-free car audio device that can realize a hands-free function simply by combining a mobile phone and a car audio device, and improve the call quality by removing howling and echo.

In general, the hands-free device is a device for preventing a traffic accident caused by the use of a mobile phone while driving by allowing the driver to drive a mobile phone while driving with both hands.

Existing mobile phone hands-free device is connected to the cigar jack of the vehicle to supply power only to provide the charging and operating voltage of the mobile phone, there is a method of using the handset of the mobile phone mounted on the cradle as it is. This method has the advantage that the structure is simple and easy to install and low cost, but due to the howling and the echo phenomenon, the call quality is poor enough that the other party can not hear the contents of the call well, resulting in discomfort. .

In addition, the hand-free set connected through the call cord of the cellular phone employs an audio amplification and filtering circuit for removing howling and echo, and is usually installed in the passenger seat space of the vehicle. This method has a separate audio amplification and filtering circuit, which removes the howling and echo phenomena to improve the call quality, but has a disadvantage in that the installation is complicated and expensive.

The object of the present invention is that the audio amplification and filtering circuit of the car audio device can be used in the hands-free mode in order to solve such problems of the prior art, so that the call quality is improved and is already set at the time of manufacturing the vehicle. It is to provide a hands-free car audio device without the inconvenience of installing.

1 is a schematic diagram for explaining the appearance of a handsfree car audio device according to the present invention;

2 is a block diagram showing a circuit configuration of a hands-free car audio device according to the present invention.

3 is a flow chart for explaining the operation of the hands-free car audio device by the present foot

<Description of the symbols for the main parts of the drawings>

100: car audio device 102: call cord connection

104: microphone 106: audio circuit

108: audio processor 110: switching means

112 power amplifier 114 power supply unit

116 control unit 200: mobile phone

210: call code 300: holder

In order to achieve the above object of the present invention, the apparatus of the present invention is provided with an audio circuit unit for outputting audio signals reproduced from at least one or more audio sources in stereo, a mobile phone call cord connection unit, in front of a driver in a vehicle, A first stereo input provided with a microphone for picking up voice, a mobile phone received voice signal provided through a call cord connection unit as an R input, and a driver's voice signal through an microphone as an L input, and stereo audio provided to the audio circuit unit An audio processor for selecting at least one second stereo input as a signal input, adjusting a high and low sound balance of the selected signal, and stereo outputting the adjusted signal; and an output corresponding to a microphone of the audio processor. Microphone output terminal of the first speaker and the call cord connection A switching means for selectively switching to one, a power amplifier for inputting and amplifying the speaker output of the switching means and the other output of the audio processor, and a pair of speakers for audio output by the output of the power amplifier; A power supply unit connected to a battery of the vehicle to generate a mobile phone battery voltage and a mobile phone operating voltage to the call cord, and a mobile phone through a call cord connection unit. In the call mode, the audio processor selects the first stereo input and controls the switching means to select the call code connection unit so that the received voice signal is output through one speaker of the pair of speakers and picked up by a microphone. The voice signal is provided with a control unit to be provided to the mobile phone It is characterized by.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the present invention through an embodiment of the present invention.

1 schematically shows an appearance of a hands-free car audio device according to the present invention. The front panel portion of the hands-free car audio device 100 of the present invention is provided with a mobile phone call cord connecting portion 102, that is, a connector. The mobile phone 200 is detachably installed on the cradle 300, and the mobile phone 200 and the car audio device 100 are connected to each other through the call cord 210. The driver's hands-free microphone 104 is installed at a suitable place in front of the driver and is electrically connected to the car audio device 100. The front L speaker FL is attached to the left side of the driver's seat, and the front R speaker FR is attached to the passenger seat right side.

The call cord connection unit 102 includes a plurality of terminals: an external speaker terminal SP, an external microphone terminal MC, a mobile phone battery charging voltage terminal B +, an operating voltage terminal VCC, and data terminals S1 to Sn), and the ground terminal G.

2 shows a circuit configuration of a hands-free car audio device according to the present invention. The hands-free audio device 100 includes an audio circuit unit 106, an audio processing unit 108, a switching unit 110, a power amplifier unit 112, a power supply unit 114, and a controller 116.

The audio circuit unit 106 receives the FM / AM radio broadcast and outputs the stereo audio signals L2 and R2 by reproducing the audio signals from the tuner unit 106a for generating the stereo audio signals L1 and R1 and the cassette tape. The tape reproducing section 106b includes an optical disc reproducing section 106c for reproducing audio data from the compact disc CD and outputting stereo audio signals L3 and R3.

The audio processor 108 inputs three stereo audio signals L1 and R1 (L2 and R2) L3 and R3 provided from the audio circuit unit 106, respectively. In addition, the audio processor 108 inputs a voice signal of the driver picked up through the microphone 104 to L4, and inputs a voice signal of the caller received through the mobile phone 200 to R4.

The audio processor 108 inputs a four-channel stereo audio signal and selects one of four pairs of input signals in response to the control signal CS1 of the controller 116 and adjusts gain and volume of the selected stereo audio signal. It consists of a one-chip audio processor, such as the TDA7437 from SGS-THOMSON, which adjusts the treble and bass, adjusts the sound balance optimally, and then outputs the sound. The one-chip audio processor communicates control data with the control unit by serial data communication.

The audio processor 1080 outputs two pairs of stereo audio signals for supplying to the front left and right speakers FL and FR installed at the front of the vehicle interior and the rear left and right speakers BL and BR installed at the rear.

The power amplifier 112 inputs and amplifies two pairs of stereo audio signals provided from the audio processor 108, respectively, and then supplies them to the front left and right speakers FL and FR and the rear left and right speakers BL and BR, respectively. do. The front amplifiers 112a and 112b and the rear amplifiers 112c and 112d of the power amplifier 112 selectively operate in response to the control signal CS2 of the controller 116.

A switching means 110 is interposed between the FL output of the audio processor 108 and the FL input of the power amplifier 112. The switching means 110 selects the input of the power amplifier 112 normally in response to the control signal CS3 of the control unit 116, and the external microphone terminal MC of the call cord connection unit 102 in the hands-free communication mode. Select.

The power supply unit 114 inputs a battery voltage provided from the battery of the vehicle in response to the control signal CS4 of the control unit 116 to generate an operating voltage VC of each unit, and charges the mobile phone battery of the call cord connection unit 102. The voltage is supplied to the voltage terminal B + and the operating voltage terminal VCC, respectively.

The control unit 116 is connected to the data terminals S1 to Sn of the call code connection unit 102 to communicate control data with the mobile phone 200. That is, serial control data, hands-free connection presence control signal, and the like are communicated through the data terminals S1 to Sn. The control unit 116 includes a microprocessor, a memory, and a peripheral circuit unit. The microprocessor controls the system by outputting a control signal for controlling each part in accordance with a corresponding mode by a normal car audio program and a hands-free program.

3 is a flowchart for explaining the operation of the hands-free car audio device according to the present invention.

The user mounts the mobile phone 200 to the cradle 300, and connects the mobile phone 200 and the hands-free car audio device 100 with the call cord 210. The control unit 116 checks the connection of the call code 210 (302), and sets the hands-free mode when the call code connection (304). That is, the control unit 116 controls the power supply unit 114 by the call cord connection to provide the battery charging voltage and the operating voltage to the mobile phone 200. Accordingly, the mobile phone battery is charged by the charging voltage provided from the power supply unit 114 of the car audio device 306 and maintained in the standby state by the provided operating voltage.

When the driver presses any key of the mobile phone for a call or receives a call signal through the mobile phone antenna in this standby state, the controller 116 recognizes this as the call mode (308). If the call mode is checked in step 308, the controller 116 checks the power-off state of the car audio device 100 (310). In the power-off state, the power supply unit 114 is controlled to provide an operating voltage VC to each unit to turn the system on (312). In step 310 and 312, if the power-on state, the current system state information is stored in the memory. System status information is shown in Table 1 below.

TABLE 1

Status mode Status Information Power off mode 0 Radio Receive Mode One Tape play mode 10 Optical Disc Playback Mode 11

Subsequently, the controller 116 stops the operation of the mode after the state information is stored, and switches the input selection of the audio processor 108 to the fourth input through the control signal CS1. That is, the control unit 316 selects the voice signal L4 picked up from the microphone 104 and the voice signal R4 provided from the mobile phone through the external speaker terminal SP as an input (316). In addition, the control unit 110 controls the switching unit 110 to select the external microphone terminal MC through the control signal CS3 (318). Also. The controller 116 disables operations of the rear amplifiers 112c and 112d of the power amplifier 112 through the control signal CS2 and enables only the front amplifiers 112a and 112b (320).

The call mode is set by such a control state. When the driver speaks while driving while holding the steering wheel with both hands in the call mode, the driver's voice is transmitted to the mobile phone 200 via the audio processing unit 108 and the switching unit 110 through the microphone 104. In the mobile phone 200, the external microphone input is processed by a conventional signal processing method and transmitted as a wireless signal.

On the other hand, the voice signal of the caller received by the mobile phone 200 is decoded and restored to the voice signal, the restored voice signal is transmitted to the audio processing unit 108 through the external speaker terminal (SP) and the bass and the audio processing unit 108 The sound signal processed by the treble and the sound balance is adjusted and output is amplified by the power amplifier 112 and then output through the front right speaker. Thus, the driver can hear the caller's voice through the front right speaker.

Since the microphone 104 is located at the left side and the hands-free speaker is located at the right side, it is possible to minimize the deterioration of the call sound quality due to howling or echo, and the audio processing unit 108 reduces noise by appropriate filtering and sound balance adjustment. You will be able to enjoy the voice quality.

In such a call state, when the driver presses the end key of the mobile phone or closes the flip, the controller 116 recognizes the end of the call (320). At the end of the call in step 320, the control unit 116 reads the previous state information stored in the memory, restores the car audio system to the previous state, and controls the system so that the operation state before the call continues. When the system recovery is completed in step 324, the step 308 is performed to maintain the standby mode.

As described above, in the present invention, by configuring the audio circuit of the car audio system to be used in combination with the hands-free system, the hands-free function can be easily and inexpensively added to the car audio system. In addition, in the present invention, by using the audio circuit of the car audio system in the hands-free mode, it is possible to reduce the existing howling and echo phenomena and to improve the call quality.

In addition, the present invention can store the state information of the previous car audio mode when entering the call mode, and can automatically restore the previous mode at the end of the call, thereby increasing the convenience of use.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the present invention without departing from the spirit and scope of the invention described in the claims below. I can understand that you can.

Claims (2)

An audio circuit unit for outputting an audio signal reproduced from at least one audio source in stereo; Cell phone call cord connection; A microphone installed in front of the driver in the vehicle and configured to pick up the driver's voice; At least a first stereo input for inputting a cellular phone received voice signal provided through the call cord connection unit and an audio input for the audio circuit unit provided with a first stereo input for inputting the driver's voice signal through the microphone as an L input; An audio processor configured to select one or more second stereo inputs, to adjust a balance between high and low frequencies of the selected signal and to stereo output the adjusted signal; Switching means for selectively switching one output corresponding to the microphone of the audio processor to one of a first speaker and a microphone output terminal of the call cord connection unit; A power amplifier configured to input and amplify the speaker output of the switching means and the other output of the audio processor, respectively; A pair of speakers for outputting voice by the output of the power amplifier; A power supply unit connected to a battery of the vehicle to generate a mobile phone battery voltage and a mobile phone operating voltage to each unit's operating voltage and the call code; The mobile phone is connected to the mobile phone through the call code connection unit, and in the hands-free mode, the charging of the battery of the mobile phone is controlled. In the call mode, the audio processor selects the first stereo input and controls the switching means to select the call code connection unit. And a control unit for outputting a received voice signal through one speaker of the pair of speakers and for supplying a voice signal picked up to a microphone to the mobile phone. The hands-free car audio device according to claim 1, wherein the controller stores the current control state in the call mode and automatically returns to the previous state with reference to the stored control state at the end of the call.