Apparatus and method for controlling noise in vehicle

A noise control apparatus for vehicles includes a noise extractor for removing an output sound from an indoor sound to extract a noise, a transmitter for transmitting the noise and vehicle information, a receiver for receiving a cancellation sound corresponding to the noise and the vehicle information and a mixer for simultaneously outputting the cancellation sound and the output sound.

This application claims the benefit of priority to Korean Patent Application No. 10-2015-0157400, filed on Nov. 10, 2015 with the Korean Intellectual Property Office, which is hereby incorporated by reference as if fully set forth herein.

TECHNICAL FIELD

The present disclosure relates to a noise control apparatus and method for vehicles and, more specifically, to an apparatus and method for cancelling noise according to information, location and a driving environment of a vehicle.

BACKGROUND

People live surrounded by numerous noise sources. Examples of noise include high-level outdoor noise such as exhaust noise of vehicles or friction sounds of tires, aircraft engine noise and noises of machines in factories and indoor noise. However, it is impossible to abandon modern conveniences in order to remove noise. Accordingly, various efforts to reduce noise generated in living environments have been made.

To control noise, a method of searching for the cause of noise and then actually decreasing the noise can be adopted. The active noise control technique is a typical noise reduction method. The active noise control technique superposes a sound wave having the same magnitude as noise and a phase (−90°) opposite the noise on the noise such that the noise and sound wave cancel each other out, thereby generating a sound shadow area. That is, the active noise control technique uses superposition and destructive interference, which are physical properties of waves. The most significant feature of this technique is to selectively cancel noise of a specific frequency. However, there are many limitations on active noise control techniques since it is difficult to generate a sound wave having an opposite phase when a noise wave has multiple forms. Particularly, a problem of delay taken to detect and analyze noise and to generate a sound wave having an opposite phase has not been adequately solved. Consequently, it is difficult to completely cancel noise. To compensate for such problems, sound quality enhancement technology has been developed. This technology changes the sound wave of noise into a sound that people can hear using the principle that a sound is heard differently when the waveform of the sound, not the magnitude thereof, is changed.

Vehicle indoor noise cancellation is a typical example. While costs can be large when attempting to remove the entire noise, costs can be reduced if only a specific noise to which people sensitively respond is reduced or eliminated. A known vehicle audio speaker is a typical case to which the sound quality enhancement technology is applied to effectively block a noise of the vehicle and outdoor noise. However, it is not easy to secure noise cancellation quality since there are various causes of vehicle indoor noise and systems for solving the same become complicated.

SUMMARY

An object of the present disclosure devised to solve the problem lies in a noise control apparatus for vehicles, which can analyze noise generated when a vehicle is driven according to the cause of the noise and then selectively cancel the noise.

Another object of the present disclosure is to provide a noise control apparatus for vehicles, which can accurately remove noise by analyzing the cause of the noise and receiving a cancellation sound source corresponding to the noise through an external service connected to a vehicle through a network and improve economic efficiency of the vehicle by minimizing components mounted in the vehicle, and a network apparatus for providing noise control information to the vehicle.

The object of the present disclosure is not limited to the aforementioned, but other objects not described herein will be clearly understood by those skilled in the art from descriptions below.

In an aspect of the present disclosure to accomplish the object, a noise control apparatus for vehicles includes: a noise extractor for removing an output sound from an indoor sound to extract a noise; a transmitter for transmitting the noise and vehicle information; a receiver for receiving a cancellation sound corresponding to the noise and the vehicle information; and a mixer for simultaneously outputting the cancellation sound and the output sound.

The cancellation sound may include a plurality of sounds corresponding to causes of the noise.

The noise control apparatus for vehicles may further include a microphone for acquiring the indoor sound; and a speaker for delivering the output sound and the output of the mixer.

The vehicle information may include at least one of a position (GPS information) of the vehicle, a speed of the vehicle and specification information of the vehicle.

The cancellation sound may include at least one of a first cancellation sound reflecting noise information according to characteristics of a road in response to at least one of a position of the vehicle, the speed of the vehicle and the specification information of the vehicle, a second cancellation sound reflecting noise information according to current weather in response to the position of the vehicle, and a third cancellation sound reflecting noise information according to the speed of the vehicle and the specification information of the vehicle.

The first cancellation sound may be generated in consideration of whether the road is an asphalt road, a concrete road or an unpaved road.

The second cancellation sound may be generated in consideration of rainfall or wind velocity.

The third cancellation sound may be generated in consideration of noise generated in the vehicle according to the speed of the vehicle and the specification information of the vehicle and noise generated outside of the vehicle.

The noise control apparatus for vehicles may further include a first converter for converting the noise into a digital signal and a second converter for converting the cancellation sound into an analog signal.

The noise may be continuously delivered through the transmitter and the cancellation sound may be continuously delivered through the receiver, during activation of a noise control operation by a user.

In another aspect of the present disclosure, a network device for providing noise control information includes: a storage unit for storing a plurality of cancellation sounds corresponding to noise and vehicle information; a receiver for receiving the noise and the vehicle information from a vehicle connected through a network; a data processor for searching the plurality of cancellation sounds for information corresponding to the noise and the vehicle information; and a transmitter for delivering a result of the data processor.

The vehicle information may include at least one of a position (GPS information) of the vehicle, a speed of the vehicle and specification information of the vehicle.

The plurality of cancellation sounds may include at least one of a first cancellation sound reflecting noise information according to characteristics of a road in response to at least one of a position of the vehicle, the speed of the vehicle and the specification information of the vehicle, a second cancellation sound reflecting noise information according to current weather in response to the position of the vehicle, and a third cancellation sound reflecting noise information according to the speed of the vehicle and the specification information of the vehicle.

The first cancellation sound may be generated in consideration of whether the road is an asphalt road, a concrete road or an unpaved road, the second cancellation sound may be generated in consideration of rainfall or wind velocity, and the third cancellation sound may be generated in consideration of noise generated in the vehicle according to the speed of the vehicle and the specification information of the vehicle and noise generated outside of the vehicle.

The network device may further include a simulation unit for performing simulation to check whether the noise is cancelled using the result of the data processor.

The data processor may search for stored noise information in the time domain, corresponding to the vehicle information, and compare the noise information with the noise in the time domain.

In another aspect of the present disclosure, a noise control method for vehicles includes: removing an output sound from an indoor sound to extract a noise; transmitting the noise and vehicle information; receiving a cancellation sound corresponding to the noise and the vehicle information; and simultaneously outputting the cancellation sound and the output sound.

The vehicle information may include at least one of a position (GPS information) of the vehicle, a speed of the vehicle and specification information of the vehicle.

The cancellation sound may include at least one of a first cancellation sound reflecting noise information according to characteristics of a road in response to at least one of a position of the vehicle, the speed of the vehicle and the specification information of the vehicle, a second cancellation sound reflecting noise information according to current weather in response to the position of the vehicle, and a third cancellation sound reflecting noise information according to the speed of the vehicle and the specification information of the vehicle.

The noise and the cancellation sound may be continuously transmitted and received during activation of a noise control operation by a user.

In another aspect of the present disclosure, as embodied and broadly described herein, an apparatus for controlling a grill of a speaker in a vehicle comprises a processing system that comprises at least one data processor and at least one computer-readable memory storing a computer program. Herein, the processing system is configured to cause the apparatus to remove an output sound from an indoor sound to extract a noise, transmit the noise and vehicle information, receive a cancellation sound corresponding to the noise and the vehicle information, and simultaneously output the cancellation sound and the output sound.

The foregoing aspects of the present disclosure are merely parts of preferred embodiments of the disclosure, and various embodiments reflecting technical features of the present disclosure can be derived and understood by those skilled in the art on the basis of the following detailed description of the disclosure.

The apparatus according to the present disclosure has the following advantages.

The apparatus according to the present disclosure can receive information, which is necessary for noise cancellation when a vehicle is driven, from an external server that stores a large amount of environmental information and noise information according thereto so as to enhance noise cancellation efficiency by overcoming limitations on information that can be provided by an apparatus mounted in the vehicle.

In addition, the present disclosure can overcome limitations on the performance and storage capacity of the apparatus mounted in the vehicle, thereby reducing noise in response to various causes of noise generated when the vehicle is driven.

The effects of the present disclosure are not limited to the above-described effects and other effects which are not described herein will become apparent to those skilled in the art from the following description.

DETAILED DESCRIPTION

The present disclosure will now be described in more detail with reference to the attached drawings. The term “module” used to signify components is used herein to aid in understanding of the components and thus should not be considered as having specific meanings or roles.

In a description of embodiments, it will be understood that, when an element is referred to as being “on” or “under” another element, it can be directly on or under another element or can be indirectly formed such that an intervening element is also present. In addition, terms such as “on” or “under” should be understood on the basis of the drawings.

The terms “a” or “an”, as used herein, are defined as one or more than one. The term “another”, as used herein, is defined as at least a second or more. The terms “including” and/or “having” as used herein, are defined as comprising (i.e. open transition). The term “coupled” or “operatively coupled” as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically.

In the description of the disclosure, certain detailed explanations of related art may be omitted when it is deemed that they may unnecessarily obscure the essence of the disclosure. The features of the disclosure will be more clearly understood from the accompanying drawings and should not be limited by the accompanying drawings. It is to be appreciated that all changes, equivalents, and substitutes that do not depart from the spirit and technical scope of the disclosure are encompassed in the disclosure.

FIG. 1illustrates an active noise control technique for vehicles according to embodiments of the present disclosure.

As shown, the active noise control technique for vehicles may simultaneously output noise12to be cancelled and a cancellation sound14having the same magnitude as the noise12and an opposite phase (−90°) to mix the noise12and the cancellation sound14(16) inside of a vehicle. As used in this application, “noise” may refer to an undesirable noise that may be filtered, canceled or reduced. When the noise12and the cancellation sound14are simultaneously output and mixed inside of the vehicle, the noise may be cancelled out and thus the magnitude of the noise wave decreases. Accordingly, a user (driver) may hear a noise-cancelled sound18. To use such active noise control technique for vehicles, it may be necessary to analyze the sound source of a noise and to generate a cancellation sound having a phase opposite, or substantially opposite, that of the noise to be cancelled.

FIG. 2illustrates a noise control technique using a filter according to embodiments of the present disclosure.

As shown, the noise control technique using a filter may transform a sound22having mixed noise/sound from the time domain into the frequency domain (Fourier transform). When the sound22having mixed noise/sound is transformed into the frequency domain, a non-noise sound24and a noise sound26can be separated from each other. The noise sound can be removed using a frequency filter28which can remove a sound of a specific frequency.

However, when the frequency region which will be removed using the frequency filter28includes part of the non-noise sound24, the noise control technique using a filter may remove the part of the non-noise sound24together with the noise sound26. For example, the noise control technique using a filter can cause non-noise sounds such as conversation, exhaust sounds and warning sounds to be distorted.

FIG. 3illustrates a noise control system for vehicles according to embodiments of the present disclosure.

As shown, the noise control system for vehicles may include a controller40for vehicles and a network server50which can be connected to the controller40through a wired/wireless network and provide noise control information.

The controller40for vehicles may be connected to a microphone32and a speaker34provided inside of the vehicle. Specifically, the controller40may include an audio device46connected to the speaker34, a noise control device42connected to the microphone32and a communication device44connected to the noise control device42. Although not shown, the microphone32and the speaker34may be connected to devices that implement audio, navigation and hands-free functions, which may be provided inside of the vehicle.

For example, the noise control device42may obtain a first sound through the microphone32. Thereafter, the noise control apparatus42may receive information on a second sound, which is not the noise, output through the speaker34from the audio device46. The noise control device42can obtain information about noise by excluding the second sound delivered from the audio device46from the first sound obtained through the microphone32. The obtained noise can be delivered to the network server50through the communication device44.

The information delivered from the controller40for vehicles to the network server50may include vehicle information as well as noise. Here, the vehicle information may include at least one of location (GPS information) of the vehicle, speed of the vehicle and specification information of the vehicle.

The network server50may include a storage unit54for storing a plurality of cancellation sounds corresponding to noise and vehicle information, a data processor56for searching the plurality of cancellation sounds for information corresponding to the noise and the vehicle information, and a transmitting/receiving unit52for receiving the noise and the vehicle information from the vehicle connected through a network or transmitting a result of the data processor. In addition, the network server50may further include a simulation unit58for simulating cancellation of noise using the result of the data processor56.

The data processor56may search the storage unit54for stored noise information in the time domain, which may correspond to the vehicle information, and compare the noise information with noise in the time domain. The data processor unit56need not transform noise and the plurality of cancellation sounds stored in the storage unit into the frequency domain for comparison.

Here, the plurality of cancellation sounds may include at least one of a first cancellation sound that reflects noise information according to characteristics of a road in response to at least one of a location of the vehicle, a speed of the vehicle and a specification information of the vehicle, a second cancellation sound that reflects noise information in response to the current weather, and a third cancellation sound source that reflects noise information according to the speed and specifications information of the vehicle.

For example, the first cancellation sound source may be generated in consideration of whether the road is an asphalt road, a concrete road or an unpaved road. The second cancellation sound source may be generated in consideration of rainfall or wind velocity. The third cancellation sound source may be generated in consideration of noise generated in the vehicle according to a speed and specification information of the vehicle and noise generated outside of the vehicle.

Referring toFIG. 3, the noise control system for vehicles may use a large-capacity server device connected through a network, instead of an embedded system provided with an active noise control (ANC) function and mounted in a vehicle. As the noise control system for vehicles may use the server device connected through a network, instead of the embedded system, the noise control system may overcome limitations of the embedded system.

Since the embedded system may be equipped with a device for ANC provided to a restricted space of a vehicle, system performance may be restricted due to space limitations. In addition, when all devices for ANC are set in an individual vehicle, vehicle costs may increase and the devices may affect the size and weight of the vehicle. There are various types and causes of noise that can be generated while a vehicle is driven and thus an algorithm for analyzing the types and causes of noise is complicated. Accordingly, it may be difficult for the embedded system having restricted performance to generate cancellation sounds for controlling noise in response to various types and causes of noise.

If the number of environmental factors to be considered is reduced without analyzing various types and causes of noise, it may be more difficult to discriminate noises to be reduced from non-noise (conversion, warning sound, acceleration tuning sound, etc.).

However, the noise control system for vehicles, which can use a server device connected through a network, can overcome limitations, such as processing or capacity limitations, of the embedded system.

For example, operation of the noise control system for vehicles can be performed as follows.

Indoor sound of the vehicle may be obtained through the microphone32.

Thereafter, the noise control device42may remove currently output sound from sound input to the microphone to extract sound with respect to indoor noise of the vehicle.

The sound with respect to the noise and vehicle information may be delivered to the network server50through the communication device44.

The network server50may analyze the sound with respect to the noise and the vehicle information to generate a cancellation sound corresponding to the cause of the noise. Thereafter, the network server50may deliver the cancellation sound to the vehicle.

The cancellation sound delivered through the communication device44may be transmitted through the speaker34to cancel out the indoor noise of the vehicle. When the audio device46outputs a sound requested by a driver or a passenger through the speaker34, the cancellation sound may be output simultaneously with an output of the audio device46and delivered through the speaker34.

When the aforementioned method is used, the driver or passenger need not be restrained from using devices in the vehicle, such as an audio system, a navigation system and a hands-free device, in order to cancel noise generated inside of the vehicle. That is, the driver or passenger can cancel noise while using other devices in the vehicle.

FIG. 4illustrates noise analysis for the noise control system for vehicles according to embodiments of the present disclosure.

As shown, a sound70including noise may include road characteristic noise72, weather characteristic noise74and non-noise76. The noise control system for vehicles may use a method of selectively cancelling noise using information stored in a database, which corresponds to a vehicle state in the time domain, instead of transforming noise into the frequency domain and removing the noise.

There are various causes of noise generated when a vehicle is driven. The network server50(refer toFIG. 3) may include a database with respect to noise, different from the embedded system.

For example, a typical cause of noise generated when a vehicle is driven is a road state. Different types of noise are generated when the vehicle travels on an unpaved road, when the vehicle travels on an asphalt road and when the vehicle travels on a concrete road. Accordingly, such noises need to be discriminated for adequate system performance. The controller40for vehicles may deliver the current vehicle position (GPS information) to the network server50. The network server50may recognize a road on which the vehicle is driven on the basis of the current vehicle position sent from the controller40for vehicles since the network server50may store and access road information about a predetermined area. Upon recognition of the road on which the vehicle is driven, the network server50may determine whether noise sent from the controller40for vehicles includes noise generated according to road state.

In addition, the network server50may obtain weather information (rain, strong winds, typhoons and the like) on the basis of the current vehicle position. The network server50may determine whether the noise sent from the control device40includes noise that can be generated according to weather using the weather information.

The vehicle information sent from the controller40for vehicles may include information about noise generated in the vehicle in addition to information about noise generated according to external environments of the vehicle, such as road state and weather. For example, the network server50may determine whether the noise sent from the controller40for vehicles includes noise such as wind noise generated when the vehicle is driven at a specific velocity using the model type and speed of the vehicle.

Although not shown, the network server50may analyze components included in the noise sent from the controller40for vehicles, generate cancellation sound capable of cancelling the components and perform a simulation for checking whether the noise sent from the controller40for vehicles can be cancelled using the cancellation sound.

Through the aforementioned analysis process, the noise control system for vehicles can construct a database using information about causes of noise that can be generated in the vehicle, analyze components included in noise delivered from the vehicle and then selectively cancel noise. Accordingly, only undesirable noise may be selectively removed without eliminating exhaust sounds, which may be artificially generated in the vehicle for the driver to feel, or perceive, acceleration of the vehicle, as well as conversation or warning sounds inside the vehicle, which correspond to non-noise.

FIG. 5illustrates a noise control apparatus for vehicles according to embodiments of the present disclosure.

As shown, the noise control apparatus80for vehicles may include a noise extractor90for removing an output sound from indoor sounds to extract noise, a transmitter94for transmitting the noise and vehicle information, a receiver96for receiving cancellation sounds corresponding to the noise and vehicle information, and a mixer100for simultaneously outputting the cancellation sound and the output sound. When the cancellation sound and the output sound are simultaneously output and mixed inside the vehicle, a portion of the output sound, which corresponds to the noise, may be cancelled and thus the waveform thereof is reduced. Accordingly, a user (driver) can hear noise-cancelled sound.

The noise control apparatus80for vehicles may further include or interwork with a microphone84for acquiring indoor sound and a speaker86for delivering the output sound and the output of the mixer.

In addition, the noise control apparatus80for vehicles may further include or interwork with a position receiver88for receiving information on the current position of the vehicle through a vehicle GPS antenna82.

The vehicle information delivered through the transmitter94may include at least one of a position (GPS information) of the vehicle, a speed of the vehicle and specification information of the vehicle.

The cancellation sound delivered through the receiver96may include a plurality of sounds corresponding to causes of noise. Specifically, the cancellation sound may include a first cancellation sound that reflects noise information according to road characteristics in response to at least one of a position of the vehicle, a speed of the vehicle and specification information of the vehicle, a second cancellation sound that reflects noise information according to current weather in response to a position of the vehicle, and a third cancellation sound that reflects noise information according to a speed and specification information of the vehicle.

For example, the first cancellation sound may be generated in consideration of whether a road is an asphalt road, a concrete road or an unpaved road. The second cancellation sound may be generated in consideration of rainfall or wind velocity. The third cancellation sound can be generated in consideration of noise generated in the vehicle according to a speed and specification information of the vehicle and noise generated outside of the vehicle.

The noise control apparatus80for vehicles may further include a first converter92for converting noise into a digital signal and a second converter90for converting the cancellation sound into an analog signal. The first converter92may deliver the noise extracted by the noise extractor90to the transmitter94and the second converter98can transmit the cancellation sound delivered through the receiver96to the mixer100.

During activation of a noise control operation by the user, that is, during operation of the noise control apparatus80for vehicles, noise generated inside of the vehicle can be continuously delivered (e.g. delivered in real time) through the transmitter94. In addition, the cancellation sound may be continuously delivered through the receiver96included in the noise control apparatus80for vehicles.

Alternatively, the mixer100may mix the cancellation sound and the output sound and then output a mixed sound.

FIG. 6illustrates a noise control method for vehicles according to embodiments of the present disclosure.

As shown, the noise control method for vehicles may include a step62of removing output sound from indoor sound to extract noise, a step64of transmitting the noise and vehicle information, a step66of receiving a cancellation sound corresponding to a noise and vehicle information, and a step68of simultaneously outputting the cancellation sound and the output sound.

Those skilled in the art will appreciate that the present disclosure may be carried out in other specific ways than those set forth herein without departing from the spirit and essential characteristics of the present disclosure.

The above embodiments are therefore to be construed in all aspects as illustrative and not restrictive. The scope of the disclosure should be determined by the appended claims and their legal equivalents, not by the above description, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.