KR101817521B1 - Vehicle and Controlling Method of Vehicle - Google Patents

Abstract

A vehicle comprises: an antenna receiving a wireless signal; a speaker outputting sound corresponding to a broadcasting signal included in the wireless signal received by the antenna; and a head unit capable of performing automatic acquisition control for changing an amplitude factor of the wireless signal while amplifying the wireless signal received by the antenna, and activating or deactivating the automatic acquisition control according to a frequency of an intermodulation noise between a plurality of noises included in the wireless signal, thereby attenuating noises due to intermodulation.

Description

[0001] The present invention relates to a method of controlling a vehicle,

The disclosed invention relates to a method of controlling a vehicle and a vehicle, and more particularly, to a vehicle and a control method of a vehicle capable of attenuating intermodulation.

Generally, a vehicle means a moving means or a transportation means that travels on a road or a line using fossil fuel, electricity, or the like as a power source.

The vehicle is positioned as a living space that provides rest to the driver beyond mere means of transport or transportation. In addition, a variety of car audio systems and video systems are installed in the vehicle to provide comfort and relaxation for the driver.

Particularly, a driver often listens for / watches an audio / video broadcast through an audio system / video system.

However, in recent years, radio signals of various frequencies have been radiated in the city center, and audio and video broadcasts are often distorted by radio signals of different frequencies. Particularly, when intermodulation noise is generated by intermodulation between radio signals of different frequencies, it is very difficult to intermodulate the intermodulation noise by using a bandpass filter.

One aspect of the disclosed invention is to provide a vehicle and a vehicle control method capable of attenuating noise due to intermodulation.

Another aspect of the disclosed invention is to provide a vehicle and a vehicle control method capable of preventing attenuation of a broadcast signal according to a frequency of noise caused by intermodulation.

A vehicle according to an aspect of the disclosed subject matter includes: an antenna for receiving a wireless signal; A speaker for outputting sound corresponding to a broadcast signal included in the radio signal received by the antenna; And an automatic gain control for changing the amplification factor of the radio signal received by the antenna is enabled and the automatic gain control is activated according to the frequency of the intermodulation noise due to intermodulation between a plurality of noise included in the radio signal Or deactivate the head unit.

The head unit may select the first noise among the plurality of noises, and may calculate the frequency of the second noise from the first frequency of the first noise and the frequency of the broadcast signal.

The head unit can select a noise having the strongest signal intensity among the plurality of noises as the first noise.

The head unit may select noise that is closest to the frequency of the broadcast signal of the frequency among the plurality of noises to the first noise.

The head unit may activate the automatic gain control if at least one of the frequencies of the plurality of noise matches the frequency of the second noise.

The head unit may deactivate the automatic gain control if the frequencies of the plurality of noise do not all match the frequency of the second noise.

Wherein the head unit calculates the strength of the intermodulation noise if at least one of the plurality of frequencies of the noise matches the frequency of the second noise, and if the ratio of the broadcasting signal to the intermodulation noise is smaller than the reference value, Automatic gain control can be activated.

Wherein the head unit calculates the intensity of the intermodulation noise if at least one of the plurality of frequencies of the noise matches the frequency of the second noise, and if the ratio of the broadcast signal to the intermodulation noise is equal to or greater than a reference value The automatic gain control can be deactivated.

Wherein the head unit comprises: an amplifier capable of automatic gain control for amplifying the radio signal and changing an amplification factor of the radio signal; A digital signal processor for extracting a broadcast signal from a signal amplified by the automatic gain control amplifier; And a controller for activating or deactivating the automatic gain control of the amplifier according to the frequency of the intermodulation noise.

According to another aspect of the present invention, there is provided a method of controlling a vehicle, comprising: receiving a radio signal; Amplifying the received radio signal; Extracting a broadcast signal from the amplified radio signal; And outputting a sound corresponding to the extracted broadcast signal, wherein the step of amplifying the received radio signal includes the step of amplifying the received radio signal according to a frequency of intermodulation noise caused by intermodulation among a plurality of noise included in the radio signal, And changing the amplification factor of the radio signal.

Wherein the step of changing the amplification factor of the radio signal comprises the steps of: selecting a first noise among the plurality of noise; And calculating a frequency of the second noise from the first frequency of the first noise and the frequency of the broadcast signal.

The selecting of the first noise among the plurality of noises may include selecting a noise having the strongest signal intensity among the plurality of noises as the first noise.

The selecting of the first noise among the plurality of noises may include selecting a noise closest to the frequency of the broadcast signal of the frequency among the plurality of noises to the first noise.

The step of changing the amplification factor of the radio signal may further include changing the amplification factor of the radio signal if at least one of the plurality of frequencies of the noise matches the frequency of the second noise.

And maintaining the amplification factor of the radio signal if the frequencies of the plurality of noise do not match the frequency of the second noise.

Calculating a strength of the intermodulation noise when at least one of the plurality of frequencies of the noise matches the frequency of the second noise; And changing the amplification factor of the radio signal if the ratio of the broadcast signal to the intermodulation noise is smaller than a reference value.

Calculating a strength of the intermodulation noise when at least one of the plurality of frequencies of the noise matches the frequency of the second noise; And maintaining the amplification factor of the radio signal if the ratio of the broadcast signal to the intermodulation noise is greater than or equal to a reference value.

According to another aspect of the disclosed subject matter, there is provided a vehicle comprising: an antenna for receiving a wireless signal; A speaker for outputting sound corresponding to a broadcast signal included in the radio signal received by the antenna; And a head unit for changing the amplification factor of the radio signal when the frequency of the intermodulation noise due to the intermodulation between the plurality of noise included in the radio signal received by the antenna matches the frequency of the broadcast signal, have.

The head unit can maintain the amplification rate of the radio signal if the frequency of the intermodulation noise due to intermodulation between the plurality of noise does not match the frequency of the broadcast signal.

Wherein the head unit activates an automatic gain control for changing an amplification factor of the radio signal if the frequency of the intermodulation noise matches the frequency of the broadcast signal, and if the frequency of the intermodulation noise does not match the frequency of the broadcast signal, Automatic gain control can be disabled.

According to an aspect of the disclosed subject matter, there is provided a method of controlling a vehicle and a vehicle capable of attenuating noise due to intermodulation.

According to another aspect of the disclosed subject matter, there is provided a method of controlling a vehicle and a vehicle capable of preventing attenuation of a broadcast signal according to a frequency of noise caused by intermodulation.

1 shows a vehicle according to an embodiment.
Fig. 2 shows electrical components of a vehicle according to an embodiment.
3 shows the interior of the vehicle according to one embodiment.
4 shows a configuration of an audio apparatus according to an embodiment.
FIG. 5 illustrates an example of a signal processing unit included in an audio apparatus according to an embodiment.
FIG. 6 illustrates noise and intermodulation noise input to an audio device according to an exemplary embodiment.
FIG. 7 shows an example of a method for removing intermodulation noise of a vehicle according to an embodiment.
Figs. 8 and 9 show the case where the frequency of the intermodulation noise and the listening frequency are matched.
10 shows a case where the frequency of the intermodulation noise and the listening frequency do not match.
11 and 12 illustrate another example of a method of eliminating intermodulation noise of a vehicle according to an embodiment.

Like reference numerals refer to like elements throughout the specification. This specification does not describe all the elements of the embodiments, and duplicate descriptions of the contents or embodiments in the technical field to which the disclosed invention belongs are omitted. The term 'part, module, member, or block' used in the specification may be embodied in software or hardware, and a plurality of 'part, module, member, and block' may be embodied as one component, It is also possible that a single 'part, module, member, block' includes a plurality of components.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only the case directly connected but also the case where the connection is indirectly connected, and the indirect connection includes connection through the wireless communication network do.

Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

Throughout the specification, when a member is located on another member, it includes not only when a member is in contact with another member but also when another member exists between the two members.

The terms first, second, etc. are used to distinguish one element from another, and the elements are not limited by the above-mentioned terms.

The singular forms " a " include plural referents unless the context clearly dictates otherwise.

In each step, the identification code is used for convenience of explanation, and the identification code does not describe the order of the steps, and each step may be performed differently from the stated order unless clearly specified in the context. have.

Hereinafter, the working principle and embodiments of the disclosed invention will be described with reference to the accompanying drawings.

1 shows a vehicle according to an embodiment. Fig. 2 shows electrical components of a vehicle according to an embodiment. Figure 3 also shows the interior of the vehicle according to one embodiment.

As shown in Fig. 1, a vehicle 1 includes a vehicle body 10 that forms an appearance of the vehicle 1 and accommodates various components, and a wheel 20 that moves the vehicle 1. As shown in Fig.

The vehicle body 10 forms an interior space in which the driver can stay, an engine room for accommodating the engine, and a trunk room for accommodating the cargo.

The vehicle body 10 includes a hood 11, a front fender 12, a roof panel 13, a door 14, a trunk lid 15, A quarter panel 16, and the like. A front window 17 is provided in front of the vehicle body 10 and a side window 18 is provided on a side surface of the vehicle body 10 in order to secure a view of the driver, A rear window 19 may be provided at the rear of the vehicle body 10.

A power generation device, a power transmission device, a steering device, a braking device, and the like may be provided inside the vehicle body 10 so that the vehicle 1 can run. The power generation device generates a rotational force and may include an engine, a fuel supply device, a cooling device, an exhaust device, an ignition device, and the like. The power transmitting device transmits the rotational force generated by the power generating device to the wheel 20, and may include a clutch, a shift lever, a transmission, a differential device, a drive shaft, and the like. The steering apparatus controls the running direction of the vehicle 1, and may include a steering wheel, a steering gear, a steering link, and the like. The braking device stops the rotation of the wheel 20 and may include a brake pedal, a master cylinder, a brake disk, a brake pad, and the like.

The wheel 20 receives rotational force from the power generating device through the power transmitting device, and can move the vehicle 1. [ The wheel 20 may include a front wheel 21 provided at the front of the vehicle and a rear wheel 22 provided at the rear of the vehicle.

The vehicle 1 may include various electrical components 30 for the safety and comfort of the driver and passenger, as well as the control of the vehicle 1, as well as the mechanical components described above.

2, the vehicle 1 includes an engine management system (EMS) 31, a transmission control unit (TCU) 32, an electronic braking system (EBS) 33, an electric power steering (EPS) 34, a body control module (BCM) 35, a heating / ventilation / air conditioning (HVAC) 36 A video device 37, and an audio device 100, as shown in FIG.

The engine management system 31 can control the operation of the engine and manage the engine according to the driver's acceleration command through the accelerator pedal 31a. For example, the engine management system 31 can perform engine torque control, fuel consumption control, engine failure diagnosis, and the like.

The transmission control module 32 can control the operation of the transmission in accordance with the shift command of the driver through the shift lever 32a or the traveling speed of the vehicle 1. [ For example, the transmission control module 32 can perform shift control, damper clutch control, pressure control at the time of friction clutch on / off, and engine torque control during shifting.

The electronic braking system 33 can control the braking device of the vehicle 1 and maintain the balance of the vehicle 1 in accordance with the braking command of the driver through the braking pedal 33a. For example, the electronic braking system 33 may include an anti-lock brake system (ABS) and an electric stability control (ESC).

The electric steering system 34 can assist the driver to easily operate the steering wheel 34a by the driver. For example, the electric power steering apparatus 34 may assist the user in steering operations such as reducing the steering force at low-speed driving or parking, and increasing the steering force at high-speed driving.

The vehicle body control module 35 can control the operation of electrical components that provide convenience to the driver or ensure the safety of the driver. For example, the vehicle body control module 35 can control a power seat installed in the vehicle 1, a remote door lock device, a power window, a head lamp, a wiper, a gauge device, and a multifunctional switch.

The video device 37 can provide various information and entertainment to the driver through video and sound. For example, the video device 37 reproduces a video file stored in an internal storage medium or an external storage medium (a compact disk (CD), a USB storage medium, or the like) according to a command from the driver, Display and sound can be output.

The video device 37 may receive a video broadcast signal, display an image included in the video broadcast, and output sound.

The audio device 100 can provide various information and entertainment to the driver through the sound. For example, the audio device 100 may reproduce an audio file stored in an internal storage medium or an external storage medium according to a command from the driver, and output sound included in the reproduced audio file. In addition, the audio device 100 can receive sound data from a user device such as a portable computer, a portable communication device, a portable media player, and the like, and output sound corresponding to the received sound data.

The audio apparatus 100 may receive an audio broadcast signal and output an audio corresponding to the received audio broadcast signal.

The specific configuration and operation of the audio apparatus 100 will be described in more detail below.

These electrical components 30 can communicate with each other through the vehicle communication network NT. For example, the engine management system 31, the transmission control module 32, the electronic braking system 33, the electric steering system 34, the body control module 35, the air conditioner 36, the video device 37, And the audio device 100 can exchange data via the vehicle communication network NT.

The vehicle communication network NT has a communication protocol such as Ethernet, MOST (Media Oriented Systems Transport), Flexray, CAN (Controller Area Network), and LIN (Local Interconnect Network) Can be adopted. Further, the vehicular communication network NT can employ not only a single communication protocol such as a modem, flex-ray, can, and lean but also a plurality of communication protocols.

The electrical components 30 described above are merely examples of electrical components installed in the vehicle 1. [ The vehicle 1 may be provided with electric components other than the electric components 30 described above or may be provided with additional electric components in addition to the electric components 30 described above, (30) may be omitted.

The configuration and operation of the audio apparatus 100 included in the vehicle 1 will be described below.

Hereinafter, an audio apparatus 100 for receiving an audio broadcast signal will be described, but the embodiment of the present invention is not limited thereto. For example, the present invention may be applied to a video device 37 that receives a video broadcast signal.

4 shows a configuration of an audio apparatus according to an embodiment. FIG. 5 illustrates an example of a signal processing unit included in an audio apparatus according to an embodiment. 6 illustrates noise and intermodulation noise input to an audio apparatus according to an exemplary embodiment.

4, the audio apparatus 100 includes an antenna module 120 for receiving a broadcast signal, a speaker module 130 for outputting sound based on the broadcast signal, and a speaker 130 for extracting an acoustic signal from the received broadcast signal. And a head unit 110 for amplifying the extracted acoustic signal.

The antenna module 120 may include an antenna 121 for receiving a broadcast signal and a low noise amplifier (LNA) 122 for amplifying the received broadcast signal.

The antenna 121 can receive a broadcast signal from the free space. The broadcast signal may include a signal having a plurality of frequencies. For example, a frequency modulation (FM) radio broadcast signal may include a broadcast signal of 89.1 MHz (Mega Hertz), a broadcast signal of 89.7 MHz, a broadcast signal of 91.9 MHz, ..., a broadcast signal of 107.7 MHz, .

The low noise amplifier 122 can amplify the broadcast signal received by the antenna 121 at a predetermined rate. It is known that the radio signal radiated into free space sharply decreases as it moves away from the source. The radio signal received by the antenna 121 also has a very low intensity and the low noise amplifier 122 can amplify the strength of the radio signal to a level that the head unit 110 can discern.

In particular, the low-noise amplifier 122 may be designed to minimize noise due to amplification, and the low-noise amplifier 122 may be provided near the antenna 121 so that noise is not added while the signal received by the antenna 121 is transmitted. .

As described above, the antenna module 120 receives a broadcast signal from the free space, amplifies the received broadcast signal, and outputs the amplified broadcast signal to the head unit 110.

The speaker module 130 may include a plurality of speakers 131, 132, and 133 that can convert electrical sound signals output from the head unit 110 into sound. For example, the speaker module 130 may include a tweeter speaker 131 capable of outputting a high frequency sound, an intermediate frequency speaker 132 capable of outputting an intermediate frequency sound, And may include a woofer speaker 133,

Each of the speakers 131, 132, and 133 may be installed at various positions within the vehicle 1. [ 3, an intermediate frequency speaker 132 is installed on the upper surface of the dashboard 40 of the vehicle 1, and a high frequency speaker 131 (not shown) is connected to the door 14 of the vehicle 1. [ And a low frequency speaker 133 may be installed.

As described above, the speaker module 130 can convert the electrical sound signal output from the head unit 110 into sound and output it.

The head unit 110 includes an input unit 111 for receiving an operator input, a display unit 112 for displaying operation information of the head unit 110, and a display unit 112 for receiving a broadcast signal from the antenna module 120, A signal processing unit 113 and a control unit 114 for controlling the operation of the head unit 110. [ In addition, the head unit 110 may further include a media reader for loading media files from an external storage medium, a communication unit for communicating with other electric components 30 of the vehicle 1, and the like.

The input unit 111 may include various input means that can be operated by the driver. For example, the input unit 111 may include a volume dial for adjusting the size of the sound, a channel selection dial for selecting the broadcast frequency of the audio broadcast, a plurality of presets for receiving the audio broadcast of the pre- And a playback button for playing an audio file stored in an external storage medium.

The input unit 111 may include various types of input means such as a push button, a slide button, and a dial.

As described above, the input unit 111 can receive an operator's operation command for the audio device 100, and can output an electrical signal corresponding to the received operation command to the control unit 114. [

The display unit 112 can display the operation information of the head unit 110 according to the operation of the driver through the input unit 111. [ For example, when the driver selects the frequency of the broadcast signal through the channel selection dial, the display unit 112 can display the frequency selected by the driver. Also, when the driver inputs a reproduction command of the audio file stored in the external storage medium, the display unit 112 can display the name of the sound source to be reproduced.

The display unit 111 may include various types of display means such as a liquid crystal display (LED), a light emitting diode (LED), and an organic light emitting diode (OLED).

In this manner, the display unit 111 can display an image representing the operation information of the head unit 110 according to a control command of the controller 114. [

5, the signal processing unit 113 includes an AGC (automatic gain control) amplifier 113a for automatically adjusting the amplification factor, a digital signal processor (DSP) receiver 113b for processing the received broadcast signal, And a power amplifier 113c for amplifying an electric sound signal output to the speaker module 130. [

The AGC amplifier 113a can amplify the broadcast signal received by the antenna module 120 according to the strength of the noise or the intensity of the output signal. For example, when the magnitude of the amplified signal is greater than a predetermined reference value, the AGC amplifier 113a reduces the gain or gain. When the magnitude of the amplified signal is smaller than a predetermined reference value, the gain is increased . Also, the AGC amplifier 113a may reduce the gain or the gain if the noise intensity is greater than a predetermined reference value, and increase the gain or gain if the noise intensity is less than the predetermined reference value.

Also, the AGC amplifier 113a may be activated or deactivated in accordance with the control signal of the control unit 114 or the DSP receiver 113b. When the automatic gain control is activated, the AGC amplifier 113a can amplify the broadcast signal received by the antenna module 120 according to the intensity of the output signal. If the automatic gain control is inactivated, the AGC amplifier 113a, The antenna module 120a can amplify the broadcast signal received by the antenna module 120 simply.

The AGC amplifier 113a reduces noise due to intermodulation and prevents the broadcast signal input to the DSP receiver 113b from being saturated. The intermodulation phenomenon is explained in detail below.

The DSP receiver 113b converts the analog broadcasting signal amplified by the AGC amplifier 113a into a digital broadcasting signal, and extracts a broadcasting signal of a specific frequency using digital signal processing. Also, the DSP receiver 113b may convert the extracted broadcast signal into an analog signal, and output the electrical acoustic signal converted into the analog signal to the power amplifier 113c.

For example, the DSP receiver 113b may convert an analog broadcast signal to a digital broadcast signal using an analog to digital conversion (ADC). Thereafter, the DSP receiver 113b analyzes the spectrum of the digital broadcasting signal using a fast Fourier transform (FFT), and extracts the broadcasting signal of the listening frequency input from the driver through the input unit 111 . Thereafter, the extracted broadcast signal can be decoded and converted into an analog sound signal using a digital to analog conversion (DAC).

The DSP receiver 113b may include a memory and a processor. The memory can store programs and data for processing broadcast signals, and the processor can process broadcast signals according to programs and data stored in the memory.

The DSP receiver 113b may be provided separately from the control unit 112 or may be integrally provided with the control unit 112, which will be described below. For example, the DSP receiver 113b may be embodied as a part of a processor included in the control part 112 or a program stored in a memory included in the control part 112. [

The power amplifier 113c can amplify the electric acoustic signal output from the head unit 110. [ The power amplifier 113c may be provided integrally with the head unit 110 or separately from the head unit 110. [

The signal processing unit 113 passes a signal belonging to the frequency band of the broadcasting signal in addition to the AGC amplifier 113a, the DSP receiver 113b and the power amplifier 113c described above and blocks a signal not belonging to the frequency band of the broadcasting signal And a band pass filter that filters the received signal.

As described above, the signal processor 113 extracts a broadcast signal having a listening frequency selected by the driver from the broadcast signal received by the antenna module 120, and outputs the sound corresponding to the extracted broadcast signal.

The control unit 114 can receive the control command from the driver 111 from the input unit 111 and can control the operation of the display unit 112 and the signal processing unit 113. [

For example, the control unit 114 may receive the listening frequency selected by the driver from the input unit 111, and may control the display unit 112 to display an image corresponding to the selected listening frequency. The control unit 114 may control the signal processing unit 114 to extract a broadcasting signal of a listening frequency from the broadcasting signal received by the antenna module 120. [

The control unit 114 may activate or deactivate the AGC amplifier 113a or adjust the amplification rate of the AGC amplifier 113a according to the intensity of the noise N-1 or N-2 received through the antenna module 120 have.

In the free space, various radio signals other than the broadcast signal can be propagated. In particular, the frequency of radio signals available to operators is determined by law. Accordingly, the noise (N-1, N-2) received through the antenna module 120 may have a frequency different from the frequency band of the broadcast signal. As described above, the noise (N-1, N-2) having a frequency different from the frequency band of the broadcast signal can be filtered using the band pass filter included in the signal processor 113.

Noise may be generated in the signal processing unit 113 due to the original noise N-1, N-2 even if the original noise N-1, N-2 is removed using the band pass filter. The sound may be distorted due to the noise generated in the signal processing unit 113.

The noise generated in the signal processing unit 113 typically includes harmonic noise and intermodulation noise.

Harmonic noise and intermodulation noise may occur while noise (N-1, N-2) passes through the nonlinear element. For example, when the noise (N-1, N-2) received through the antenna module 120 passes through the AGC amplifier 113a and corresponds to an integer multiple of the frequencies of the noises (N-1, N-2) Intermodulation noise having a frequency corresponding to a harmonic noise having a frequency and a combination of the frequencies of the noise (N-1, N-2) may occur.

For example, when the input signal x is input to the nonlinear element, the nonlinear element can output the output signal y, and the output signal y can be expressed by Equation (1).

[Equation 1]

Here, y represents an output signal, x represents an input signal, and G ₀ , G ₁ , G ₂ , and G ₃ represent amplification rates of respective orders.

When the input signal x includes two noise N-1, N-2 having different frequencies (? ₁ ,? ₂ ), the input signal x can be expressed as in Equation (2) have.

&Quot; (2) "

Here, x represents the input signal, A represents the amplitude of the first noise,? ₁ represents the frequency of the first noise, B represents the amplitude of the second noise,? ₂ represents the frequency of the second noise , t can represent the time.

At this time, the output signal y can be expressed by Equation (3).

y represents the output signal, x represents an input _{signal, G 0, G 1, G} 2, G 3 represents the amplification factor of each order, A represents the amplitude of the first noise, ω ₁ is the first noise B denotes the amplitude of the second noise,? ₂ denotes the frequency of the second noise, and t denotes the time.

According to the equation (3), the input signal x is amplified by the amplification ratio G ₁ and output. However, the output signal (y) may be high with the amplification ratio (G ₁₎ of the input signal (x) as the amplification comprises a power term.

The quadratic term of the output signal y can be summarized as shown in Equation (4).

&Quot; (4) "

y represents the output signal, x represents an input _{signal, G 0, G 1, G} 2, G 3 represents the amplification factor of each order, A represents the amplitude of the first noise, ω ₁ is the first noise B denotes the amplitude of the second noise,? ₂ denotes the frequency of the second noise, and t denotes the time.

The third term of the output signal y can be summarized as shown in Equation (5).

&Quot; (5) "

y represents the output signal, x represents an input _{signal, G 0, G 1, G} 2, G 3 represents the amplification factor of each order, A represents the amplitude of the first noise, ω ₁ is the first noise B denotes the amplitude of the second noise,? ₂ denotes the frequency of the second noise, and t denotes the time.

According to Equation (4) and Equation (5), the output signal y may include harmonic noise and intermodulation noise.

For example, if the first frequency a second noise (N-2) of (f ₁₎ a first noise (N-1) and a second frequency (f ₂₎ of the input to the nonlinear device, the first frequency (f ₁ Harmonic noise having frequencies 2f ₁ , 3f ₁ , ... corresponding to an integral multiple of the second frequency f ₂ and harmonics having frequencies 2f ₂ , 3f ₂ , Noise can be output. Also, the first frequency (f ₁₎ and the second frequency (f ₂₎ is the combined frequencies (f ₁ + f _2, f ₁ -f _2, 2f ₁ + f _2, f _{1 2} + 2f, 2f ₁ -f ₂ , 2f ₂ -f ₁ , ...) may be output.

2f ₁ -f ₂ and mutually with a frequency of 2f ₂ -f ₁ modulated noise (hereinafter, respectively "the first intermodulation noise" and is referred to as "second intermodulation noise") is the original noise (N-1, N- 2). ≪ / RTI > 6, the frequencies of the first intermodulation noise IM3-1 and the second intermodulation noise IM3-2 are the first noise N-1 and the second noise N-1, respectively, 2).

Therefore, when the difference between the frequencies of the noises (N-1, N-2) and the listening frequency is not large, the first intermodulation noise IM3-1 and the second intermodulation noise IM3-2, There is a possibility that the sound output from the audio device 100 may be distorted due to the first intermodulation noise IM3-1 and the second intermodulation noise IM3-2.

In order to prevent this, the controller 114 can activate / deactivate the AGC amplifier 113a or control the amplification factor of the AGC amplifier 113a according to the intensity and frequency of the noise signal.

The control unit 114 may include a processor and a memory. The memory may store a program and data for controlling the operation of the head unit 110 and the processor may output a control signal for controlling the operation of the head unit 110 according to programs and data stored in the memory .

The remedial operation of the control unit 114 will be described in detail below.

FIG. 7 shows an example of a method for removing intermodulation noise of a vehicle according to an embodiment. Figs. 8 and 9 show the case where the frequency of the intermodulation noise and the listening frequency are matched. 10 shows a case where the frequency of the intermodulation noise and the listening frequency do not match.

7, 8, 9 and 10, a method 1000 for eliminating the intermodulation noise of the vehicle 1 is described.

The vehicle 1 selects a listening frequency according to the driver's selection (1010).

The driver can select the frequency of the broadcast signal to be heard through the head unit 110 of the vehicle 1. [ For example, in the case of selecting an FM radio broadcast signal, the driver can select a broadcast using the input unit 111 of the head unit 110, and the input unit 111 outputs a signal related to the listening frequency selected by the driver And output it to the control unit 114. [

The control unit 114 may receive the signal related to the listening frequency from the input unit 111 and may output the channel selection control signal to the signal processing unit 113 so that the signal processing unit 113 outputs the broadcasting signal corresponding to the listening frequency.

Vehicle 1 filters out a plurality of noises and predicts the frequency of intermodulation noise due to noise (1020).

Noises of undesired frequencies may be received through the antenna module 120 while the audio device 100 of the vehicle 1 receives the broadcast signal through the antenna module 120. [ For example, in urban areas, signals at various frequencies are emitted at a strong intensity, so that stronger noise may be received than broadcast signals.

The audio apparatus 100 may pass a broadcast signal through the band-pass filter provided in the antenna module 120 or the head unit 110 to block noise.

As described above, the audio apparatus 100 can block the noise having a different frequency from the broadcasting signal using the band pass filter. However, if the frequency of the intermodulation noise generated by the mutual modulation between the noise is similar to the frequency of the broadcasting signal, It is difficult for the receiver 100 to block intermodulation noise using a bandpass filter.

For this reason, the audio apparatus 100 can detect noise having an intensity that is equal to or higher than a predetermined threshold, and can calculate the frequency of the intermodulation noise from the frequency of the sensed noise.

For example, the audio apparatus 100 can calculate the frequency of the intermodulation noise using Equations (4) and (5) described above. The audio device 100 as shown in Figure 8 comprises a first noise (N-1) a first frequency (f ₁₎ and the intermodulation noise from the second frequency (f2) of the second noise (N-2) of the can calculate the frequency _{(2f 1 -f 2, 2f 2} -f 1) of (IM3-1, IM3-2).

Vehicle (1) judges that the inter-modulation noise frequency _{(2f 1 -f 2, 2f 2} -f 1) the driver is listening to the selected frequency and the matching of (IM3-1, IM3-2) (1030) .

Frequency of the vehicle 1. The audio apparatus 100 includes a frequency _{(2f 1 -f 2, 2f 2} -f 1) and listening broadcast signal (S) of the intermodulation noise (IM3-1, IM3-2) of (f ₀ And judges whether or not the frequencies 2f ₁ -f ₂ and 2f ₂ -f _{1 of the} intermodulation noise signals IM3-1 and IM3-2 match the frequency f ₀ of the listener broadcast signal S can do.

Specifically, the audio apparatus 100 determines whether the frequencies (2f ₁ -f ₂ , 2f ₂ -f ₁ ) of the intermodulation noise signals IM3-1 and IM3-2 and the frequency (f ₀ ) of the listen broadcast signal S are as well as to determine whether the match, the frequency of the frequency _{(2f 1 -f 2, 2f 2} -f 1) and listening broadcast signal (S) of the intermodulation noise _{(IM3-1, IM3-2) (f 0} ) May be determined to be within a predetermined error range.

If the frequency (f ₀₎ of the frequency _{(2f 1 -f 2, 2f 2} -f 1) and listening broadcast signal (S) of the intermodulation noise (IM3-1, IM3-2) match, the vehicle 1 is automatically The gain control is activated (1040).

As shown in FIG. 8, when the frequencies 2f ₁ -f ₂ and 2f ₂ -f _{1 of the} intermodulation noise signals IM3-1 and IM3-2 are matched with the frequency f ₀ of the listener broadcast signal S The audible broadcast signal S and the intermodulation noise IM3-1 and IM3-2 are output through the speaker module 130 so that the sound of the broadcast signal can be distorted.

In order to prevent the distortion of the broadcast signal and attenuate the intensities of the intermodulation noise signals IM3-1 and IM3-2, the audio apparatus 100 can activate automatic gain control of the AGC amplifier 113a.

According to Equation (5), the intensity of the intermodulation noise (IM3-1, IM3-2) is proportional to the third power of the intensity of the noise (N-1, N-2). In other words, as the strength of the noises (N-1, N-2) decreases, the intensities of the intermodulation noise (IM3-1, IM3-2) may decrease more sharply. Therefore, when the automatic gain control is activated, the amplification factor of the AGC amplifier 113a can be reduced according to the intensity of the noises N-1 and N-2, and the intensity of the intermodulation noise IM3-1 and IM3-2 Can be drastically reduced.

For example, when the automatic gain control of the AGC amplifier 113a is activated, the amplification factor of the AGC amplifier 113a is reduced and the noise N-1, N -2) is decreased. Further, the intensities of the intermodulation noise signals IM3-1 and IM3-2 are drastically reduced due to the reduction of the intensities of the noises N-1 and N-2.

As a result, the sound of the broadcast signal due to the intermodulation noise IM3-1 or IM3-2 can be prevented from being distorted.

If the frequency (f ₀₎ of the frequency _{(2f 1 -f 2, 2f 2} -f 1) and listening broadcast signal (S) of the intermodulation noise (IM3-1, IM3-2) match, the vehicle 1 is automatically Gain control is disabled (1050).

The frequencies 2f ₁ -f ₂ and 2f ₂ -f _{1 of the} intermodulation noise signals IM3-1 and IM3-2 and the frequency f ₀ of the listener broadcast signal S are not matched The intermodulation noise signals IM3-1 and IM3-2 may be interrupted by the DSP receiver 113b. Therefore, the intermodulation noise signals IM3-1 and IM3-2 are not outputted through the speaker module 130, and the sound of the broadcast signal is not distorted.

Even when the sound of the broadcast signal is not distorted, the AGC amplifier 113a can adjust the amplification factor according to the strength of the noise. At this time, not only the noise but also the intensity of the broadcast signal can be reduced by adjusting the amplification rate of the AGC amplifier 113a. In this way, the audio apparatus 100 can disable the automatic gain control in order to prevent the intensity of the broadcast signal from being reduced even though the sound of the broadcast signal is not distorted.

As a result, the broadcast signal can be output from the AGC amplifier 113a to the DSP receiver 113b without being distorted or attenuated, as shown in Fig.

As described above, the audio apparatus 100 of the vehicle 1 calculates the frequencies of the intermodulation noise IM3-1 and IM3-2 due to the noises N-1 and N-2, The automatic gain control can be activated or deactivated according to the frequencies (2f ₁ -f ₂ , 2f ₂ -f ₁ ) of the noises (IM3-1, IM3-2).

The frequencies 2f ₁ -f ₂ and 2f ₂ -f _{1 of the} intermodulation noise IM3-1 and IM3-2 are calculated from the frequencies f ₁ and f ₂ of the noises N-1 and N-2 to is calculated, it was a method in which the automatic gain control of the AGC amplifier (113a) is enabled or disabled in accordance with the described inter-modulation noise frequency _{(2f 1 -f 2, 2f 2} -f 1) of (IM3-1, IM3-2) .

Hereinafter, a first noise (N-1) frequency of (f ₁₎ from the listening frequency (f ₀₎ and the intermodulation noise matching (IM3-1, IM3-2) a second noise (N-2 capable of generating ) Will be described.

11 and 12 illustrate another example of a method of eliminating intermodulation noise of a vehicle according to an embodiment.

11 and 12, a method 1100 for eliminating intermodulation noise of the vehicle 1 is described.

The vehicle 1 selects the listening frequency according to the driver's choice (1110).

The driver can select the frequency of the broadcast signal to be heard through the head unit 110 of the vehicle 1. [ For example, in the case of selecting an FM radio broadcast signal, the driver can select a broadcast using the input unit 111 of the head unit 110, and the input unit 111 outputs a signal related to the listening frequency selected by the driver And output it to the control unit 114. [

The control unit 114 may receive the signal related to the listening frequency from the input unit 111 and may output the channel selection control signal to the signal processing unit 113 so that the signal processing unit 113 outputs the broadcasting signal corresponding to the listening frequency.

The vehicle 1 searches for noise having an intensity that is greater than or equal to the reference intensity, and generates a list of the frequencies and the intensity of the detected noise (1120).

Noises of undesired frequencies may be received through the antenna module 120 while the audio device 100 of the vehicle 1 receives the broadcast signal through the antenna module 120. [ For example, in urban areas, signals at various frequencies are emitted at a strong intensity, so that stronger noise may be received than broadcast signals.

The audio apparatus 100 measures the strength of the noise N-1 and N-2 received through the antenna module 120 and determines whether the intensity of the noise N-1 or N-2 is equal to or higher than the reference intensity can do. Also, the audio apparatus 100 can store the frequencies (f ₁ , f ₂ ) of the noise (N-1, N-2) having the intensity of the signal higher than the reference intensity. In addition, the intensity of the noise (N-1, N-2) having the intensity of the signal equal to or higher than the reference intensity can be stored as a list.

The vehicle 1 selects the main noise from the frequency list of the noises N-1 and N-2 and calculates the frequency of the candidate noise from the frequency of the main noise and the frequency f ₀ of the listener broadcast signal S (1130). Herein, the candidate noise represents a noise that generates an intermodulation noise that is matched to a broadcast broadcasting signal by intermodulation phenomena with the main noise.

The audio device 100 of the vehicle 1 can select the main noise from the frequency list of noise N-1, N-2 in various ways. For example, the audio apparatus 100 selects the noise having the highest signal intensity among the received noise N-1 and N-2 as the main noise or the noise among the received noise N-1 and N-2 The noise whose frequency is closest to the frequency band of the broadcast signal can be selected as the main noise. Of course, the audio device 100 may arbitrarily select the main noise.

Thereafter, the audio apparatus 100 can calculate the frequency of the candidate noise from the frequency of the main noise and the frequency (f ₀ ) of the listener broadcast signal S. The candidate noise represents a noise that can generate the intermodulation noise that is matched to the listener broadcast signal by intermodulation phenomena with the main noise. In other words, the frequency of the intermodulation noise generated by the intermodulation of the main noise and the candidate noise can be matched with the frequency of the listening broadcast signal.

The frequency of the candidate noise can be calculated by the following equations (6) and (7).

&Quot; (6) "

Here, f _candidate represents the frequency of the candidate noise, f _main represents the frequency of the main noise, and f ₀ represents the frequency of the broadcast broadcasting signal.

&Quot; (7) "

Here, f _candidate represents the frequency of the candidate noise, f _main represents the frequency of the main noise, and f ₀ represents the frequency of the broadcast broadcasting signal.

The vehicle 1 searches 1140 for a list of frequencies of noise based on the frequency of the candidate noise.

The audio device 100 of the vehicle 1 can retrieve the frequency that matches the frequency of the candidate noise in the frequency list of noise. In other words, the audio device 100 can search for a frequency equal to or at least within an error range of the frequency of the candidate noise in the frequency list of noise.

The vehicle 1 determines whether a frequency that matches the frequency of the candidate noise is found in the frequency list of noise 1150 and if a frequency that matches the frequency of the candidate noise in the list of frequencies of noise is found 1150, 1) calculates the intensity of the intermodulation noise due to the main noise and the candidate noise (1160).

If a frequency that matches the frequency of the candidate noise is found in the list of frequencies of noise, intermodulation noise may be generated by intermodulation between the found candidate noise (noise having a frequency matching the frequency of the candidate noise) and the main noise And the frequency of the intermodulation noise can be matched with the frequency of the listening broadcast signal.

Thus, if a frequency matching the frequency of the candidate noise is found in the frequency list of noise, the audio device 100 of the vehicle 1 can obtain the intensity of the main noise and the intensity of the candidate noise from the list of frequencies and intensities .

Also, the audio apparatus 100 can calculate the intensity of the intermodulation noise from the intensity of the main noise and the intensity of the candidate noise using Equation (5).

The vehicle 1 determines whether the sum of the strength of the listening broadcast signal and the allowable range is less than the intensity of the intermodulation noise (1170). Here, the allowable range may indicate the strength of a signal that is distorted even if the sound of the broadcast broadcast signal is disturbed due to the intermodulation noise, at a level that the driver can perceive.

The audio apparatus 100 of the vehicle 1 can compare the strength of the intermodulation noise with the sum of the strength of the listening broadcast signal and the allowable range. If the sum of the strength of the listening broadcast signal and the allowable range is less than the intermodulation noise, the sound of the listened broadcast signal may be distorted and the driver may feel uncomfortable. In addition, if the sum of the strength of the listened broadcast signal and the allowable range is equal to or greater than the intermodulation noise, the sound of the listened broadcast signal may be distorted to some extent, but the degree of distortion may not be uncomfortable to the driver.

In the embodiment, the sum of the strength and the allowable range of the listening broadcast signal is compared with the intensity of the intermodulation noise, but the present invention is not limited thereto. For example, the ratio of the intensity of the listening broadcast signal to the intensity of the intermodulation noise, i.e., the signal-to-noise ratio, can be calculated, and the signal-to-noise ratio can be compared with the reference value.

If the sum of the strength of the listening broadcast signal and the allowable range is less than the intensity of the intermodulation noise (example of 1170), the vehicle 1 activates automatic gain control (1180).

If the sum of the strength of the listening broadcast signal and the allowable range is less than the intensity of the intermodulation noise, the listening broadcast signal may be distorted due to the intermodulation noise caused by the main noise and the candidate noise, Can be uncomfortable.

Therefore, in order to prevent the distortion of the broadcast signal and attenuate the intensity of the intermodulation noise, the audio apparatus 100 can activate the automatic gain control of the AGC amplifier 113a.

When the automatic gain control of the AGC amplifier 113a is activated, the amplification factor of the AGC amplifier 113a can be reduced according to the intensity of the noise, and the intensity of the intermodulation noise can also be drastically reduced.

Therefore, the distortion of the sound of the listener broadcast signal due to the intermodulation noise can be mitigated.

In the embodiment, the sum of the strength and the allowable range of the listening broadcast signal is compared with the intensity of the intermodulation noise, but the present invention is not limited thereto. For example, if the signal-to-noise ratio is smaller than the reference value, the ratio of the intensity of the listening broadcast signal to the intensity of the intermodulation noise, i.e., the signal-to-noise ratio is calculated. Control can be activated.

On the other hand, if no frequency matching the frequency of the candidate noise is found in the list of frequencies of noise (NO in 1150), or if the sum of the strength of the listening broadcast signal and the allowable range is not less than the intensity of the intermodulation noise (1) deactivates automatic gain control (1190).

If a frequency that matches the frequency of the candidate noise is not found in the list of frequencies of noise, the frequency of the intermodulation noise due to intermodulation between the noise does not match the frequency of the listening broadcast signal. As a result, the sound of the listening broadcast signal due to the intermodulation noise is not distorted, and the audio apparatus 100 can disable the automatic gain control so that the listening broadcast signal is not attenuated.

Even if a frequency matching the frequency of the candidate noise is found in the list of frequencies of noise, if the sum of the strength of the listening broadcast signal and the allowable range is not less than the intensity of the intermodulation noise, distortion of the sound of the listening broadcast signal due to the intermodulation noise This does not inconvenience the driver. Thus, the audio device 100 may disable the automatic gain control so that the listening broadcast signal is not attenuated.

In the embodiment, the sum of the strength and the allowable range of the listening broadcast signal is compared with the intensity of the intermodulation noise, but the present invention is not limited thereto. For example, the ratio of the intensity of the listening broadcast signal to the intensity of the intermodulation noise, i.e., the signal-to-noise ratio, is calculated, and if the signal-to-noise ratio is not less than the reference value, the audio device 100 determines the automatic gain of the AGC amplifier 113a Control can be deactivated.

As described above, the audio apparatus 100 of the vehicle 1 can select the main noise among the plurality of noises and calculate the frequency of the candidate noise from the frequencies of the main noise and the listening broadcast signal. In addition, the audio apparatus 100 activates the automatic gain control when noises having a matching frequency of the frequency of the candidate noise are found, and deactivates the automatic gain control if noise having a matching frequency of the frequency of the candidate noise is not found .

The operations described above are not limited to audio devices, and may be applied to video devices that receive video broadcast signals.

Meanwhile, the disclosed embodiments may be embodied in the form of a recording medium storing instructions executable by a computer. The instructions may be stored in the form of program code and, when executed by a processor, may generate a program module to perform the operations of the disclosed embodiments. The recording medium may be embodied as a computer-readable recording medium.

The computer-readable recording medium includes all kinds of recording media in which instructions that can be decoded by a computer are stored. For example, it may be a ROM (Read Only Memory), a RAM (Random Access Memory), a magnetic tape, a magnetic disk, a flash memory, an optical data storage device, or the like.

The embodiments disclosed with reference to the accompanying drawings have been described above. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. The disclosed embodiments are illustrative and should not be construed as limiting.

1: vehicle 100: audio device
110: head unit 113: signal processing unit
113a: AGC amplifier 113b: DSP receiver
114: control unit 120: antenna module
130: Speaker module

Claims (20)

An antenna for receiving a wireless signal;
A speaker for outputting sound corresponding to a broadcast signal included in the radio signal received by the antenna; And
Wherein the automatic gain control is enabled by changing the amplification factor of the radio signal received by the antenna and the automatic gain control is activated according to the frequency of the intermodulation noise caused by intermodulation between the plurality of noise included in the radio signal And a head unit for deactivating the head unit. The method according to claim 1,
Wherein the head unit selects a first noise among the plurality of noises and calculates a frequency of a second noise from the first frequency of the first noise and the frequency of the broadcast signal. 3. The method of claim 2,
Wherein the head unit selects noise having the strongest signal intensity among the plurality of noises as the first noise. 3. The method of claim 2,
Wherein the head unit selects noise that is closest to the frequency of the broadcast signal of the frequency among the plurality of noises to the first noise. 3. The method of claim 2,
Wherein the head unit activates the automatic gain control if at least one of the frequencies of the plurality of noise matches the frequency of the second noise. The method of claim 3,
Wherein the head unit deactivates the automatic gain control if the frequencies of the plurality of noise do not all match the frequency of the second noise. The method of claim 3,
Wherein the head unit calculates the strength of the intermodulation noise if at least one of the plurality of frequencies of the noise matches the frequency of the second noise, and if the ratio of the broadcasting signal to the intermodulation noise is smaller than the reference value, A vehicle that activates automatic gain control. The method of claim 3,
Wherein the head unit calculates the intensity of the intermodulation noise if at least one of the plurality of frequencies of the noise matches the frequency of the second noise, and if the ratio of the broadcast signal to the intermodulation noise is equal to or greater than a reference value And deactivates the automatic gain control. The method according to claim 1,
The head unit includes:
An amplifier capable of automatic gain control for amplifying the radio signal and changing an amplification factor of the radio signal;
A digital signal processor for extracting a broadcast signal from a signal amplified by the automatic gain control amplifier; And
And a controller for activating or deactivating automatic gain control of the amplifier according to the frequency of the intermodulation noise. Receiving a radio signal;
Amplifying the received radio signal;
Extracting a broadcast signal from the amplified radio signal; And
And outputting a sound corresponding to the extracted broadcast signal,
Wherein the step of amplifying the received radio signal comprises:
And modifying the amplification factor of the radio signal according to the frequency of the intermodulation noise caused by intermodulation between a plurality of noise included in the radio signal. 11. The method of claim 10,
The step of changing the amplification factor of the radio signal includes:
Selecting a first noise among the plurality of noises; And
And calculating a frequency of a second noise from the first frequency of the first noise and the frequency of the broadcast signal. 12. The method of claim 11,
Wherein the step of selecting the first noise among the plurality of noise includes:
And selecting noise having a strongest signal strength among the plurality of noises as a first noise. 12. The method of claim 11,
Wherein the step of selecting the first noise among the plurality of noise includes:
And selecting a noise closest to a frequency of the broadcast signal of the frequency among the plurality of noises as a first noise. 12. The method of claim 11,
The step of changing the amplification factor of the radio signal includes:
And changing the amplification factor of the radio signal if at least one of the plurality of frequencies of the noise matches the frequency of the second noise. 12. The method of claim 11,
Further comprising the step of maintaining the amplification factor of the radio signal if the frequencies of the plurality of noises do not match the frequency of the second noise. 12. The method of claim 11,
The step of changing the amplification factor of the radio signal includes:
Calculating a strength of the intermodulation noise if at least one of the plurality of frequencies of the noise matches the frequency of the second noise; And
And changing the amplification factor of the radio signal if the ratio of the broadcast signal to the intermodulation noise is smaller than a reference value. 12. The method of claim 11,
The step of changing the amplification factor of the radio signal includes:
Calculating a strength of the intermodulation noise if at least one of the plurality of frequencies of the noise matches the frequency of the second noise; And
And maintaining the amplification factor of the radio signal if the ratio of the broadcast signal to the intermodulation noise is greater than or equal to a reference value. An antenna for receiving a wireless signal;
A speaker for outputting sound corresponding to a broadcast signal included in the radio signal received by the antenna; And
And a head unit for changing the amplification factor of the radio signal when the frequency of the intermodulation noise due to intermodulation between a plurality of noise included in the radio signal received by the antenna matches the frequency of the broadcast signal. 19. The method of claim 18,
Wherein the head unit maintains the amplification rate of the radio signal when the frequency of the intermodulation noise due to intermodulation between the plurality of noise does not match the frequency of the broadcast signal. 19. The method of claim 18,
Wherein the head unit activates an automatic gain control for changing an amplification factor of the radio signal if the frequency of the intermodulation noise matches the frequency of the broadcast signal, and if the frequency of the intermodulation noise does not match the frequency of the broadcast signal, Vehicle that disables automatic gain control.

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