KR20110131985A - Audio system for removement of engine noise in a vehicle - Google Patents

Abstract

PURPOSE: An audio system with an engine sound removing function is provided to reduce costs by removing a need for additional components to remove engine sound, to remove original engine sound and play virtual engine sound preferred by a driver. CONSTITUTION: An audio system with an engine sound removing function comprises an amplifier and a speaker. The amplifier comprises a microphone, an AD converter(21), a DSP(Digital Signal Processor, 22), a DA converter(23), and a microcomputer(25). The AD converter receives engine sound from the microphone and converts the engine sound to a digital engine sound signal. After the DSP forms a digital engine sound signal input from the AD converter and an out-phase signal, the DSP synthesizes the digital engine sound signal with the out-phase signal to remove an engine sound signal.

Description

AUDIO SYSTEM FOR REMOVEMENT OF ENGINE NOISE IN A VEHICLE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio system of a vehicle, and more particularly, to an audio system capable of removing a vehicle engine sound using an antiphase of the engine sound.

In vehicles, functions such as playing music using car audio have been developed. In-vehicle multimedia environment has become a basic function of the vehicle, and the rate of listening to music in the vehicle rather than at home is increasing.

Rather than trying to mechanically remove the engine sound of a vehicle by developing such a function, a new technology for reducing engine noise by using a high-performance DSP (Digital Signal Processor) used in multimedia is emerging. Using the capabilities of existing multimedia products, it is possible to control the engine noise flowing into the vehicle from the function of simply playing music.

Recently, new technologies such as removing engine noise introduced into a vehicle or generating engine sounds desired by a user have emerged.

The technological development of the existing engine noise canceling has made a lot of advances, and its functions have been commercialized in mobile phones and headphones, and have already been applied to some vehicles.

Typically, as shown in FIG. 1, a vehicle audio system includes a head unit 110 for processing audio signals of various formats, an amplifier 120 for performing CAN (Controller Area Network) communication with the head unit 110, and It includes a plurality of speakers 130 connected to the amplifier 120.

As a method for removing general engine sound, a method of removing one part of engine noise by installing one or two microphones in a vehicle, forming an anti-phase component of current engine noise, and outputting them to a speaker is provided. As shown in FIG. 2, the engine sound removing system of the conventional vehicle is output from the engine noise removing unit 112 and the head unit 110 for converting the engine noise input from the microphone 111 into a reverse phase and outputting the reversed phase. An output synthesis circuit 113 for synthesizing and outputting the sound source and the antiphase engine sound, and an amplifier 120 for amplifying and outputting the synthesized sound.

However, conventionally, functions are implemented in an inefficient structure that receives a microphone input and additionally configures a module to use a high performance DSP. That is, the engine sound removing system of the conventional vehicle should further comprise the engine noise removing unit 112 and the output synthesis circuit 113, accordingly the number of parts and manufacturing cost increases.

The present invention provides an audio system that can easily remove engine sounds by reproducing an engine sound by using an amplifier of an audio system of a vehicle when starting a vehicle.

According to an embodiment of the present invention, a vehicle engine sound-removable audio system comprising an amplifier and a speaker, wherein the amplifier receives an engine sound from the microphone, the microphone, converts the digital engine sound signal, and outputs an AD converter; The digital engine sound signal input from the AD converter and an antiphase signal are formed, and then synthesized with the digital engine sound signal to remove the engine sound signal and output the audio signal from the DSP. And a microcomputer controlling the DA converter output to the speaker and the DSP and the DA converter.

The vehicle includes a selection unit for selecting any one of an engine sound removing function and a virtual engine sound reproducing function, the amplifier further includes a storage unit storing at least one virtual engine sound signal, and the micom is the engine sound. If the remove function is selected, the DSP is controlled to remove the input digital engine sound. If the virtual engine sound reproduction function is selected, the DSP is controlled to remove the input digital engine sound, and then the virtual engine is removed from the storage unit. Preferably, a sound is read out and provided to the DSP to reproduce the virtual engine sound.

The amplifier is provided with an input terminal for receiving an engine sound input from the microphone, and when the microcomputer recognizes that the start of the vehicle is turned on, it is preferable to turn on the operation of the microphone.

Preferably, the DSP checks the phase of the input signal in real time, and if the input signal is above a predetermined level, judges that the engine sounds and forms an antiphase signal to synthesize the input signal with the antiphase signal. .

Preferably, a power IC for amplifying the analog signal output from the DA converter is further provided between the DA converter and the speaker.

By such a configuration, the engine sound can be easily removed by using the amplifier of the audio system of the vehicle at the start of the vehicle, and the cost reduction can be realized because no additional configuration for removing the engine sound is needed in the audio system. In addition, it is possible to remove the original engine sound and reproduce the virtual engine sound desired by the driver.

1 is a connection diagram of a general head unit and an amplifier.
2 is a block diagram of a system for removing conventional engine noise.
3 is a diagram illustrating a connection between a microphone and an amplifier according to an exemplary embodiment.
4 is a diagram illustrating an internal configuration of an amplifier according to an embodiment.
5 is a diagram illustrating an internal configuration of an amplifier according to an embodiment.

The present invention provides a microphone input stage for removing engine noise in a vehicle amplifier, and adds a DA (Digital / Analog) converter to remove engine noise or reproduce virtual engine sounds using a high-performance DSP of a conventional amplifier. do.

3 is a diagram illustrating a connection between the microphone 10 and the amplifier 20 in an audio system of a vehicle according to an exemplary embodiment. As shown in FIG. 3, a microphone input terminal (not shown) is provided in the amplifier 20 so that the input signal of the microphone 10 is input to the amplifier 20.

4 is a block diagram of an amplifier 20 according to an embodiment. As shown in FIG. 4, the amplifier 20 according to an embodiment includes an analog / digital converter (AD) 21 receiving a signal from the microphone 10, and a digital signal processor (DSP) 22 processing an audio signal. ), The power IC 24 and the DSP 22 which amplify the signal output from the DA (Digital / Analog) converter 23 connected to the output terminal of the DSP 22 and the DA converter 23 and output the amplified signal to the speaker 30. ) And a microcomputer 25, a RAM 26, and a ROM 27 that control the DA converter 23.

The RAM 26 and the ROM 27 serving as storage units store data for program and audio processing for the operation of the amplifier 20. Also, the ROM 27 stores audio signals related to the plurality of virtual engine sounds so that the DSP 22 reproduces various virtual engine sound signals. Here, the microcomputer 25 preferably reads the audio signal corresponding to the selected virtual engine sound from the ROM 27 and provides it to the DSP 22 based on the predetermined virtual engine sound reproduction selection by the driver. Thereby, the original engine sound can be removed and the virtual engine sound desired by the driver can be reproduced.

The microcomputer 25 turns on the microphone 10 when the on / off state of the ignition key or the RPM of the engine reaches a predetermined value (for example, 600 RPM) or more through CAN communication with the vehicle.

In addition, the microcomputer 25 recognizes which of the engine sound removing button and the virtual engine sound reproduction button provided in advance in the operation unit of the head unit are selected through CAN communication with the head unit (not shown). Then, the microcomputer 25 controls the DPS 22 according to the selected button to completely remove the engine sound or to reproduce the virtual engine sound after removing the engine sound.

The DSP 22 checks in real time whether the noise of the input signal is above a certain level, forms an inverse phase of the engine sound and synthesizes it with the input digital engine sound, thereby removing the engine sound.

When the microcomputer 25 detects the generation of the engine sound through the CAN communication, the microphone 10 is turned on. When the engine sound is input through the microphone 10, the AD converter 21 converts the engine sound into a digital engine sound signal and outputs it to the DSP 22.

The microcomputer 25 recognizes whether the engine sound is removed or the virtual engine sound is selected through CAN communication. When the microcomputer 25 recognizes that the engine sound removal is selected, the microcomputer 25 controls the DSP 22 to form a signal of the inverse phase of the engine sound input by the DSP 22, and then inputs the digital engine sound signal and the antiphase signal. Is synthesized and output to the DA converter 23.

On the other hand, when the microcomputer 25 recognizes that the virtual engine sound reproduction is selected, the virtual engine sound corresponding to the selection is read from the ROM 27 and provided to the DSP 22 by the head unit to control the DSP 22. The DSP 22 reproduces the input virtual engine sound signal. As a result, a virtual engine sound desired by the driver can be formed and output.

The DA converter 23 converts the audio signal output from the DSP 22 to analog and outputs it to the speaker 30 through the power IC 24.

Thus, in the system for removing the conventional engine noise, the engine noise canceling unit and the output combining circuit can be removed, thereby reducing the weight of the conventional system. Cost savings can also be realized because no additional configuration is required for the system. At this time, it is possible under the condition that the sound amplifier is mounted.

In addition, it is possible to implement a desired engine sound using digital signal processing techniques as well as noise reduction of the engine sound.

In addition, in the conventional engine sound removing system, it can be implemented in an efficient structure using the performance of the sound amplifier which is a multimedia component in the module type configuration. That is, the conventional additional module can be completely removed by using a sound system in the vehicle.

10 microphone 20 amplifier
21: AD converter 22: DSP
23: DA Converter 24: Power ID
25: Micom 26: RAM
27: Rom 30: Speaker

Claims (5)

An audio system that can remove vehicle engine sounds
Including an amplifier and a speaker,
The amplifier includes an AD converter for receiving an engine sound from a microphone, the microphone, and converting the engine sound into a digital engine sound signal, and forming an antiphase signal with a digital engine sound signal input from the AD converter. A vehicle engine sound comprising a DSP for synthesizing and removing an engine sound signal, a DA converter for converting an audio signal output from the DSP into an analog signal and outputting the analog signal to the speaker, and a microcomputer for controlling the DSP and the DA converter. Removable audio system. The method of claim 1,
The vehicle includes a selector for selecting any one of an engine sound removing function and a virtual engine sound reproduction function.
The amplifier further includes a storage unit for storing at least one virtual engine sound signal,
The microcomputer controls the DSP to remove the input digital engine sound when the engine sound removing function is selected, and removes the input digital engine sound by controlling the DSP when the virtual engine sound reproduction function is selected. And a virtual engine sound is read from the storage unit and provided to the DSP to reproduce the virtual engine sound. The method of claim 1,
The amplifier is provided with an input terminal for receiving the engine sound input from the microphone,
The micom is to turn on the operation of the microphone when it is recognized that the start of the vehicle, the vehicle engine sound removable audio system. The method of claim 1,
The DSP checks the phase of the input signal in real time, and if the input signal is above a predetermined level, judges that the engine sound and forms an antiphase signal to synthesize the input signal and the antiphase signal. Audio system that can remove vehicle sound. The method of claim 1,
And a power IC configured to amplify an analog signal output from the DA converter between the DA converter and the speaker.

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