JPH10206180A - Navigation sound output apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a driver to recognize an advancement direction of a vehicle (left turn, right turn, straight) even when a navigation sound cannot be heard clearly. SOLUTION: In a navigation sound output apparatus, when a navigation sound signal is input, a navigation sound is output at least from two speakers 17a, 17b set right and left in a vehicle room. When the navigation sound guides a left turn, the sound input to a left ear is made larger than the sound input to a right ear by a sound volume control means (13, 16, 19). When the navigation sound guides a right turn, the sound input to the right ear is made larger than that input to the left ear.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation voice output device, and more particularly to a navigation voice output device for outputting guidance voice (navigation voice) of a navigation device from at least two speakers disposed on the left and right sides of a vehicle interior.

[0002]

2. Description of the Related Art In a navigation system which guides a vehicle so that a driver can easily reach a desired destination, a vehicle position is detected and map data around the vehicle position is detected from a CD-ROM. The map image is read out and drawn on the display screen, and a vehicle position mark (own vehicle position mark) is drawn on a predetermined location on the map image. Then, as the current position changes due to the movement of the vehicle, the own vehicle position mark on the screen is moved, or the own vehicle position mark is fixed at a predetermined position such as the center of the screen and the map is scrolled. The surrounding map information can be understood at a glance.

Such a navigation device has a function of setting a guidance route from a departure point to a destination, a function of displaying the guidance route on a map, a guidance at an intersection on the guidance route (an enlarged view of an intersection, a display of a traveling direction, The vehicle is provided with an intersection guidance function for giving an instruction of the traveling direction by voice. The set guidance route is stored in the navigation device by continuously storing nodes (latitude and longitude and intersection identification flags) constituting the route in a memory. At the time of actual traveling, a search is made for a guidance route included in the map display area of the screen from the node sequence stored in the memory, and the guidance route is displayed so as to be distinguishable from other roads. When the vehicle is within a predetermined distance, an intersection guide map (an enlarged view of the intersection and an arrow indicating the traveling direction at the intersection) is displayed, and which road should be traveled and which direction should be traveled at the intersection are displayed. . The traveling direction is instructed by voice. For example, if the direction of travel at an intersection is a right turn, you will be directed to this point on the right, if you turn left, you will be this point on the left, if you are going straight ahead, you will be guided to this point, etc. If the distance from the current vehicle position to the intersection is a considerable distance, voice guidance such as "It's been a while" will be given as appropriate.

[0004]

The sound output of the current navigation device is difficult to hear due to car audio output sound, engine sound, road noise, and the like, and there is a case where voice guidance in a traveling direction at an intersection or the like is missed. . For this reason, in the conventional navigation device, the driver needs to frequently see the navigation screen during driving, which is not preferable for safe driving. Therefore, an object of the present invention is to provide a vehicle in a traveling direction (left turn, left turn, etc.) even when the navigation sound cannot be clearly heard.
(Right turn, straight ahead) is to be easily recognized by the driver.

[0005]

According to the present invention, there is provided a navigation audio output device which receives a navigation audio signal and outputs navigation audio from at least two speakers arranged on the left and right sides of a vehicle interior. If the navigation voice is left turn guidance, the voice input to the left ear is made louder than the voice input to the right ear, and if the navigation voice is right turn guidance, the voice input to the right ear is input to the left ear. This is achieved by a navigation audio output device provided with a volume control unit that makes the volume louder than the audio. There is a case where the navigation sound cannot be clearly heard due to sounds such as a car audio output sound, an engine sound, and road noise (noise for the navigation sound). Even in such a case, whether the guidance sound is heard from the left side, from the right side, or from the front can be easily recognized by the driver's hearing. Thus, in the case of left turn guidance, voice guidance is heard from the left side, in the case of right turn guidance, voice guidance is heard from the right side, and in the case of straight ahead guidance / other voice guidance, it is heard from the front. In this way, even if the voice guidance cannot be heard clearly due to noise, the driver can recognize the direction in which the voice guidance was heard, and the vehicle can proceed in that direction.

[0006] Specifically, the above problems are (1) when the left and right ear positions of the driver are the first and second observation points, a transfer characteristic for outputting a target signal at each observation point is set. A target response setting unit for outputting a signal obtained by convolving the transfer characteristic with the navigation voice signal as a target signal at each observation point, (2) a detection signal detected at each observation point and a target signal at each observation point Means for outputting an error signal which is the difference between the error signal at the observation sound point and the navigation voice signal, and performs adaptive signal processing so that the power of each error signal is minimized. An adaptive signal processing device which determines coefficients and applies a signal obtained by performing a filtering process to a navigation audio signal by an adaptive filter to left and right speakers; (4)
Set the target signal output transfer characteristic of each observation point in the target response setting section so that the voice input to the left ear during left turn guidance is higher than the voice input to the right ear, and voice input to the right during right turn guidance Is achieved by a navigation sound output device including means for setting a target signal output transfer characteristic of each observation point in a target response setting unit so that the target signal output transfer characteristic of each observation point is larger than the sound input to the left ear.

Further, according to the present invention, the first filter coefficient determined so that the voice input to the left ear at the time of guiding the left turn is larger than the voice input to the right ear at the time of guiding the left turn, Means for storing a second filter coefficient determined such that the sound input to the right side is louder than the sound input to the left ear, the first and second filter coefficients being appropriately set, and the input navigation A filter for applying a filtering process according to the set filter coefficient to the audio signal to input to the first and second speakers, a first filter coefficient for left turn when the left turn is set in the filter, and a right filter for right turn when the right turn This is achieved by a navigation sound output device provided with filter coefficient switching means for setting the second filter coefficient of the above filter to the filter.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

(A) Description of Adaptive Equalizer The present invention develops an audio device having an adaptive equalizer configuration, and configures a navigation voice output device. Therefore, the adaptive equalizer which is the basis of the present invention will be described first. FIG. 1 is a basic configuration diagram of an adaptive equalization system. 1 is an audio source that outputs an audio signal x (n), 2 is a target response characteristic (impulse response characteristic) T, and the audio signal x (n) is A target response setting unit that inputs and outputs a target signal d (n), 4 is a microphone that detects sound at a listening position (observation point) in the vehicle interior acoustic space, and 5 is a detected music signal d ^ (n). Target response setting unit 2
An arithmetic unit for calculating an error e (n) from a target signal d (n) output from the adaptive signal processing unit 6 for generating a signal y (n) such that the power of the error e (n) is minimized. The device 7 is a speaker that emits a sound corresponding to the signal y (n) to the vehicle interior acoustic space 8.

The target response setting section 2 has a delay characteristic of the time t, where t is a signal delay time from the output end of the audio source 1 to the microphone 4 via the speaker 7. In addition, a flat characteristic (a characteristic of gain 1) is set in the entire audio frequency band. That is, the target response setting unit 2 is provided with a flat frequency characteristic of a gain 1 as shown in FIG. 2A and a characteristic in which the impulse response has a delay time t as shown in FIG. 2B. You. The target response setting unit 2 can be realized by setting the coefficient of a tap corresponding to the delay time t of the FIR digital filter to 1, and setting the coefficients of other taps to 0. For example, assuming that one sampling period of audio data is τ and the delay time is t, this can be realized by setting the coefficient of the t / τth tap of the FIR digital filter to 1 and setting the other coefficients to 0.

[0010] The adaptive signal processing device 6 generates an audio signal x
(n) is input as a reference signal and the operation unit 5
The error signal e (n) output from the
The adaptive signal processing is performed so that the signal power is minimized, and the signal y (n) is output. The adaptive signal processing device 6 includes an adaptive signal processing unit (LMS) 6a, an adaptive filter 6b having a FIR digital filter configuration, and a propagation characteristic of a sound propagation system from the speaker 7 to the listening position for the audio signal x (n) ( Transfer function) C ^ is convolved to generate a reference signal (filtered reference signal) r (n) for use in adaptive signal processing.

The adaptive signal processing section 6a receives the error signal e (n) at the listening position and the reference signal r (n) for adaptive signal processing input via the signal processing filter 6c, and listens using these signals. The adaptive signal processing is performed so that the music signal d ^ (n) at the position becomes equal to the target signal d (n), and the coefficient of the adaptive filter 6b is determined. For example, the adaptive signal processing unit 6a determines the coefficient of the adaptive filter 6b according to the well-known LMS (Least Mean Square) adaptation algorithm so that the power of the error signal e (n) is minimized. The adaptive filter 6b subjects the audio signal x (n) to digital filter processing according to the coefficient determined by the adaptive signal processing unit 6a, and outputs a signal y (n). Therefore, if the coefficients of the adaptive filter 6b converge so that the power of the error signal e (n) is minimized by the adaptive signal processing, the music signal d ^ (n) becomes equal to the target signal d (n) at the listening position. That is, an effect is obtained in which the same sound as when the sound is heard in the ideal space of the transfer characteristic T (frequency characteristic is flat) set in the target response setting unit 2 can be heard.

As shown in FIG. 3, the adaptive filter 6b has N
It is composed of a tap FIR digital filter. For example, the input signal is sequentially delayed by one sampling time (N−
1) delay elements DL ₁ , DL ₂ ... DL _N−1, and coefficients w ₀ (n), w ₁ (n), w ₂ (n).
_N multiplying units ML ₀ , ML ₁ ,... M for multiplying _N−1 (n)
L _N−1 and the adders AD ₀ and A that sequentially add the outputs of the multipliers
It is implemented by D ₁ ··· AD _N-1. That is, the current time n
X (n) of audio signals at ts, w ₀ the coefficients of the multipliers at the time _{(n), w 1 (n} ), w 2 (n) ··· w N-1 (n), the output signal y (n), the adaptive filter 6b is given by

[0013]

(Equation 1) And outputs a signal y (n).

As shown in FIG. 4, the filter 6c has an FIR
Type digital filter.
(M-1) delay elements delayed by the next one sampling time
DL ₁, DL_Two... DL_M-1And the coefficient c for each delay element output
₀, C₁, C_Two... c_M-1Multiplication units ML for multiplying₀, M
L₁, ... ML_M-1And the addition of
Arithmetic part AD₀, AD₁... AD_M-1Is realized. coefficient
c₀, C₁, C_Two... c_M-1Is the secondary sound propagation system (viewed from the speaker)
Determined to simulate the propagation characteristics of the system up to the measurement point)
I have. The audio signal at time n · Ts is output as x (n).
If the force (filtered X signal) is r (n), the filter 6c
Is

[0015]

(Equation 2) And outputs a filtered X signal r (n).

The adaptive signal processing section 6a outputs the adaptive filter 6 at the next time (n + 1) · Ts after one sampling time Ts.
coefficient w ₀ (n + 1), w ₁ (n + 1), w ₂ (n + 1)... w _N−1 (n +
1) is replaced by coefficients w ₀ (n), w ₁ (n), and w at the current time n · Ts.
₂ (n)... W _N−1 (n), an error signal e (n), and a filtered X signal r (n) are determined by the following coefficient update formula.

[0017]

(Equation 3)

However, the j-th filter coefficient updating equation is given by w _j (n + 1) = w _j (n) + αr (nj) e (n) (4). In equation (3), (n) is the value at the current sampling time, (n + 1) is the value after one sampling time, and (n-1) is 1
The value before the sampling time, (n−2) means the value two sampling times before,.... Α is a constant that determines a step of updating the coefficient of the adaptive filter, and is set to an appropriate value. In the processing by the filtered XLMS adaptive algorithm, the operations of the above equations (1) to (3) are performed within one sampling time, and a signal y (n) is output.

As described above, the adaptive signal processing unit 6a receives the error signal e (n) at the listening position and the adaptive signal processing reference signal r (n) input via the filter 6c.
Using these signals, the music signal d ^ (n) at the listening position
Is determined so as to be equal to the target signal d (n) to determine the coefficients of the adaptive filter 6b. The adaptive filter 6b subjects the audio signal x (n) to digital filter processing according to the coefficient determined by the adaptive signal processing unit 6a, and outputs a signal y (n). Therefore, if the coefficient of the adaptive filter 6b converges to a predetermined value so that the power of the error signal e (n) is minimized by the adaptive signal processing, the signal has the transfer characteristic T set in the target response setting unit 2 at the listening position. An effect equivalent to listening to sound in space can be obtained.

(B) First Embodiment of Navigation Audio Output Device of the Present Invention (a) Overall Configuration FIG. 5 is a configuration diagram of a navigation audio output device of the present invention, and includes a plurality of observation points in a vehicle interior acoustic space. For example, an adaptive equalizer is provided so that the amplitude and phase characteristics of the navigation sound signal at the right ear and the left ear of the driver have desired characteristics.

In the figure, reference numeral 11 denotes a navigation voice S _NV (=
x (n)), and a traveling direction signal LRTS indicating whether it is a right turn voice guide, a left turn voice guide, or a straight ahead voice guide. _{Reference numeral} 13 denotes a target response setting unit, to which the navigation voice signal _SNV is input, and to the navigation voice signal _SNV , transfer characteristics T ₁ and T ₂ according to each observation point (right ear and left ear of the driver) are set. Then, signals obtained by convolving the transfer characteristics T ₁ and T ₂ with the navigation voice signal are output as target signals d ₁ (n) and d ₂ (n) at each observation point. The method of determining the transfer characteristics T ₁ and T ₂ will be described later, but the point is that (1) if the navigation sound is left turn guidance, the sound input to the left ear will be louder than the sound input to the right ear. (2) In the case of right turn guidance, the voice input to the right ear should be louder than the voice input to the left ear. The transfer characteristics T ₁ and T ₂ are determined so that the voice to be input is equal to the voice to be input to the right ear, and (4)
Predetermined transfer characteristics T ₁ and T ₂ are set according to the right turn guidance, left turn guidance, straight ahead guidance / other voice guidance.

FIG. 6 is a block diagram of the target response setting section 13. Reference numeral 13a denotes a transfer characteristic T ₁ for generating a target signal d ₁ (n) of a navigation sound at the first observation point (right side of the driver). The transfer characteristic setting unit 13b to be set is the second
A transmission characteristic setting unit transfer characteristic T ₂ in order to generate the target signal d ₂ (n) of the navigation voice at the observation point (the driver left ear) is set.

Returning to FIG. 5, reference numerals 14a and 14b denote microphones for detecting sounds at the first and second observation points (right and left ears of the driver) in the vehicle interior acoustic space, and 15a and 15b denote detected audio signals d ₁ ^. (n), d ₂ ^ (n) and errors e ₁ (n), e ₁ between target signals d ₁ (n), d ₂ (n) output from target response setting section 13
An operation unit 16 for calculating ₂ (n) is a signal y for minimizing the power of the errors e ₁ (n) and e ₂ (n) at each of the observation points.
₁ (n), adaptive signal processing device for generating a _{y 2 (n), 17a,} 1
Reference numeral 7b denotes left and right speakers for radiating a sound corresponding to the signals y ₁ (n) and y ₂ (n) to the vehicle interior acoustic space 18, and 19 denotes a navigation sound of right turn guidance, left turn guidance, straight ahead guidance / others. A transfer characteristic switching unit that sets predetermined transfer characteristics T ₁ and T ₂ in the target response setting unit 13 according to voice guidance.

(B) Adaptive signal processing device The adaptive signal processing device 16 includes a 1-input / 2-output adaptive filter 16a and a filtered X signal (signal processing reference signal).
16b for generating the signal and the adaptive signal processing unit 1
6c. The adaptive filter 16a generates a sound signal _{y 1 (n) ~y 2 (} n) by performing a predetermined filtering process on the navigation voice _{S NV (= x (n)} ), input the signal the speakers 17a, 17b, I do. Filtered X
The signal creation filter 16b outputs the navigation audio signal x
(n) shows each speaker 17a in the vehicle interior acoustic space 18,
Propagation elements C ₁₁ to 17b to microphones 14a and 14b
C ₂₂ is convoluted to generate a signal processing reference signal r ₁₁₁ (n) 〜r
Outputs ₂₂₁ (n). FIG. 7 shows a propagation characteristic (transfer characteristic) C ₁₁ -from each loudspeaker to each microphone in the vehicle interior acoustic space.
It is a block diagram of a filter 16b for creating filtered-X signal generated using a C _22.

The adaptive signal processing section 16c generates the error signals e ₁ (n) to e ₂ (n) at each observation point and the reference signal generation filter 1
6b, filtered X signal r ₁₁₁ (n) to r
₂₂₁ (n) is input, and using these signals, adaptive signal processing is performed so that the power of the error signals e ₁ (n) to e ₂ (n) at each observation point is minimized, and the coefficients of the adaptive filter 16 a are calculated. decide. Audio signals output from the adaptive filter _{16a y 1 (n) ~y 2} (n) is not to directly reach each observation point, and reaches under the influence of the frequency and phase characteristics of the vehicle interior acoustic space 18. For this reason, the adaptive signal processing unit 16c
A filtered X LMS (MEFX LMS) using signals obtained by adding the characteristics of the vehicle interior acoustic space 18 to these audio signals without using the navigation audio signals x (n) as they are.
The algorithm is adopted. That is, in the filtered X LMS algorithm, the coefficient of the adaptive filter 16a is updated using a signal obtained by filtering the navigation audio signal x (n) by the filter 16b (filtered X signal) and an error signal at each observation point.

FIG. 7 shows a filter for generating a filtered x signal.
16b, 16b₁₁~ 16b _{twenty two}Is the vehicle interior acoustic space
18, the propagation characteristic Cij from each speaker to the microphone
Is a FIR digital filter realizing the following. filter
16b indicates that all propagation signals are required for the navigation audio signal x (n).
Elemental characteristic C₁₁~ C_{twenty two}Convolved with the filtered X signal r
₁₁₁(n) -r₂₂₁(n) is output. Sand
The first speaker 17 is added to the navigation audio signal x (n).
Propagation element C from a to the first and second observation points₁₁~ C_{twenty one}Make
Let me use the filtered X signal r₁₁₁(n) -r₂₁₁Output (n)
Then, the second speaker 17 is added to the navigation audio signal x (n).
Propagation element C from b to the first and second observation points₁₂~ C_{twenty two}Make
Let me use the filtered X signal r₁₂₁(n) -r₂₂₁Output (n)
I do. Note that R₁₁(n) = (r₁₁₁(n), r₂₁₁(n)) R_{twenty one}(n) = (r₁₂₁(n), r₂₂₁(n)).

[0027] Figure 8 is a block diagram of an adaptive filter 16a, 16a ₁₁ ~16a ₂₁ is a FIR type digital filter coefficient W ₁₁ to _W-21 is set. Audio signal y ₁ to be input to the first speaker 17a (n) is obtained by inputting a navigation voice signal x (n) to the digital filter 16a ₁₁ ~16a _21, the navigation voice signal x
audio signal y ₂ to be input to the second speaker 17b (n) is obtained by the (n) input to the digital filter 16a _21.

The adaptive signal processing unit 16a performs one sampling.
Adaptive filter at next time (n + 1) · Ts after time Ts
The coefficient Wij (w of 16aij (i = 1, 2; j = 1)₀(n + 1), w₁(n +
1), w _Two(n + 1) ・ ・ ・ w_N-1(n + 1)) at the current time n · Ts
Coefficient Wij (w₀(n), w₁(n), w_Two(n) ・ ・ ・ w_N-1(n))
And the error signal e (n) and the filtered X signal Rij (n) to R
_ijUsing (n-N + 1), the following coefficient update equation

(Equation 4) decide.

In the equation (5), (n) is the value at the current sampling time, (n-1) is the value one sampling time before, (n-2) is the value two sampling times before, (n + 1) Means a value from the current time to the next sampling time. Therefore, R _ij (n-N + 1)
Means the output of the filter 16b according to the navigation audio signal before (N-1) sampling time,..., R
_ij (n-1) is a filter output according to the navigation audio signal one sampling time before, and R _ij (n) is a filter output according to the navigation audio signal at the current time.
Μ is a constant (step size parameter) of 1 or less that determines the step of updating the coefficient of the adaptive filter.
Set to an appropriate value. e _n is first a difference signal between the detection audio signal and the target signal at the second observation point (error signal), R _ij (n), e _n each of which is expressed as follows.

[0030]

(Equation 5)

According to the signal processing device 16, the adaptive signal processing section 16c outputs the filtered X signals r ₁₁₁ (n) to r ₂₂₁ (n) output from the filter 16b and the error at the first and second observation points. Based on the signals e ₁ (n) to e ₂ (n), the adaptive signal processing is executed in accordance with the equation (5) to determine the coefficients W _{11 to} W ₂₁ of the FIR digital filters constituting the adaptive filter 16a. and the adaptive filter 16a is input to the speaker 17a~17b generates a speech signal _{y 1 (n) ~y 2 (} n) is input to the navigation voice signal x (n), the speaker generates an audio sound The power of the error signals e ₁ (n) and e ₂ (n) at the first and second observation points is minimized.

FIG. 9 shows the number of audio signals = 1, the number of speakers = 2,
FIG. 3 is a configuration diagram of a specific signal processing device 16 when the number of observation points (the number of microphones) = 2. 16a is a coefficient W ₁₁ -formed by two FIR digital filters 16a _{11 to} 16a _21.
An adaptive filter for setting W ₂₁ , 16 b is a filter for creating a filtered X signal in which each of the propagation elements C ₁₁ , C ₂₁ , C ₁₂ , and C ₂₂ in the acoustic space in the vehicle cabin is constituted by a digital filter, 16 c-1
~16c-2 is an adaptive signal processing section for calculating the adaptive coefficient W ₁₁ to _W-21 of the adaptive filter in accordance with the respective Mef.times. LMS algorithm.

(C) Method of Determining Transfer Characteristics Set in Target Response Setting Unit 13 FIG. 10 is an explanatory diagram of a method of determining transfer characteristics set in the target response setting unit 13, and FIG. ,
(B) shows the case of determining the transfer characteristic during right turn guidance, and (c) shows the case of determining the transfer characteristic during straight / other guidance. For example, in order to determine the transfer characteristics at the time of left turn guidance, microphones ML and MR are arranged at the left ear and right ear of the model MDL in a predetermined acoustic room, and one speaker SPK is arranged on the left side of the model MDL. I do. For example, the angle θ = 3
0 ^{0-45 0} within the range of the range of the distance L = 1~1.5m placing speakers. In this state, the white noise signal WH is generated by the FFT analyzer ALZ and input to the speaker SPK via the audio circuit ADC. FFT analyzer ALZ microphone ML arranged on the left and right ear, receives the detection signal of the MR, the impulse response characteristic (transfer characteristic) of the speaker SPK to the right ear by performing a known FFT analysis T ₁ and the left ear from the speaker SPK determining the transmission characteristic T ₂ of the up. These transfer characteristics T ₁ and T ₂ are transfer characteristics set in the target response setting unit 13 during left turn guidance.

Similarly, as shown in FIG.
In ^{0-45 0} within the range of the distance L = 1~1.5m to place the speaker SPK transfer characteristics T ₂ of the from transfer characteristic T ₁ and a speaker SPK from the speaker SPK to the right ear to the left ear decide. These transfer characteristics T ₁ and T ₂ are the transfer characteristics set in the target response setting unit 13 during right turn guidance. Further, the transfer characteristic from the transfer characteristics T ₁ and a speaker SPK for the range in front of the model MDL distance 1~1.5m as shown in (c) by placing the speaker SPK from the speaker SPK to the right ear to the left ear to determine the T _2. These transfer characteristics T ₁ and T ₂ are transfer characteristics set in the target response setting unit 13 during straight-ahead guidance / other guidance.

[0035] The gain G ₂ of the transfer characteristic T ₂ of the time left which was measured by the above method is larger than the gain G ₁ of the transfer characteristic T _1, gain G ₁ of the transfer characteristic T ₁ of the at turning right transfer characteristic T ₂ the greater becomes than the gain G _2, the gain G ₁ of the linear guide / other when the guide transfer characteristic T ₁ is substantially equal to the gain G ₂ of the transfer characteristic T _2. Therefore, the transfer characteristics are not measured, and the transfer characteristics T ₁ and T ₂ are changed to the gains G ₁ and G ₂ as described with reference to FIG.
And the delay times τ ₁ and τ ₂ alone, determine the gain G ₂ when turning left to be larger than the gain G ₁ , and determine the gain G ₁ when turning right to be larger than the gain G ₂ ,
It may be determined that G ₁ = G ₂ at the time of straight guidance / other guidance.

The (d) The from comes to the navigation voice output control voice guidance mode navigation device 11 outputs the traveling direction signal LRTS with navigation voice S _NV, transfer characteristic switching section 19 is the traveling direction signal LRT
Based on S, a distinction is made between left turn guidance, right turn guidance, straight ahead guidance / other guidance. If it is a left turn guidance, the transfer characteristics T ₁ and T ₂ for the left turn obtained by the method described with reference to FIG. 10 are set in the transfer characteristic setting units 13 a and 13 b (FIG. 6) of the target response setting unit 13. In the case of right turn guidance, right turn transfer characteristics T ₁ and T ₂ are set in the transfer characteristic setting units 13 a and 13 b of the target response setting unit 13. Set T ₁ and T ₂ . As a result,
(1) Target signal d at the driver's left ear at the time of left turn guidance
₂ (n) becomes larger than the right target signal d ₁ (n), and (2)
When turning right, the amplitude of the target signal d ₁ (n) at the driver's right ear becomes larger than the left target signal d ₂ (n), and (3) the amplitude of the right target signal d ₁ (n) during straight-ahead guidance / other guidance. It becomes equal to the amplitude of the left target signal d ₂ (n).

When the target signals d ₁ (n) and d ₂ (n) are set as described above, the volume input to the driver's left ear during the left turn guidance is changed to the volume input to the right ear by adaptive equalization control. Even if the driver cannot clearly hear the guidance voice due to the noise, the driver can easily recognize that the vehicle is turning left and can turn right. Also, at the time of right turn guidance, the volume input to the driver's right ear becomes larger than the volume input to the left ear, and the driver can recognize that it was a right turn guidance even if he could not hear the guidance voice clearly due to noise, You can turn right correctly. Also, during straight-ahead guidance / other guidance, since the volume input to the driver's left and right ears is equal and voice guidance can be heard from the front, the driver can go straight / other guidance even if the driver cannot hear the guidance voice clearly due to noise. It is possible to recognize that there is, and it is possible to continue straight traveling or running on the road.

(C) Second Embodiment of the Navigation Voice Output Device of the Present Invention In the first embodiment, the transfer characteristics T ₁ and T ₂ set in the target response setting section 13 are switched according to left turn / right turn / straight guidance. In such a case, the adaptive filter 16a
It takes time for the coefficient to converge to a certain value, and there is a slight time delay before the guidance sound can be heard from the left side when guiding left turn, from the right side when guiding right turn, and from the front when guiding straight ahead. I do. Therefore, the transfer characteristics T ₁ and T ₂ for the left turn are set in the target response setting unit 13 in advance, and the filter coefficient convergence value of the adaptive filter 16a when the navigation sound or the white noise signal is input is measured and stored. Similarly, the transfer characteristic for right turn and the transfer characteristic for straight ahead are set in the target response setting unit 13, and the filter coefficient convergence value of the adaptive filter is measured and stored. In the actual control, the left turn filter coefficient is set to the adaptive filter at the time of left turn guidance, the right turn filter coefficient is set to the adaptive filter at the time of right turn guidance, and the straight ahead filter coefficient is set to the adaptive filter at the straight guide / other guidance. . In this way, the guidance voice can be immediately heard from the left side when guiding left turn, from the right side when guiding right turn, and from the front side when guiding straight ahead without delay.

FIG. 11 is a block diagram of a second embodiment of the navigation voice output device according to the present invention. The same parts as those in the first embodiment of FIG. In the figure, reference numeral 11 denotes a navigation sound _SNV (= x (n)) and a traveling direction signal LRTS indicating whether it is a right turn voice guide, a left turn voice guide, or a straight ahead voice guide. Is a navigation device that outputs the same. 16a is a filter unit, 16a
a ₁₁ ~16a ₂₁ is FIR type digital filter coefficient W ₁₁ to _W-21 is set, 17a, 17b are left and right speakers,
Reference numeral 18 denotes an acoustic space, reference numeral 31 denotes a driver, and reference numeral 32 denotes a filter coefficient storage unit. (1) Filter coefficients W _11R and W _21R set in the filter unit 16a during right turn guidance, and (2) set in the filter unit 16a during left turn guidance. Filter coefficients W _11L , W _21L ,
(3) storing the filter coefficients W _11C and W _21C set in the filter section 16a at the time of straight-ahead guidance / other guidance;
Reference numeral denotes a filter coefficient switching unit that sets a predetermined filter coefficient in the filter unit 16a according to whether the navigation sound is right turn guidance, left turn guidance, straight-ahead guidance / other voice guidance.

The left folding for / right turn for / linear filter coefficients _{(W 11L, W 21L / W} 11R, W 21R / W 11 C, W 21C) is a previously left for / right turn in the configuration of the first embodiment / The straight-line transfer characteristics T ₁ and T ₂ are set in the target response setting unit 13, and
Input navigation voice or white noise signal,
The filter coefficient convergence value of the adaptive filter 16a at that time is measured and obtained and stored in the storage unit 32. Since the navigation device 11 becomes a voice guidance mode outputs the traveling direction signal LrTS with navigation voice S _NV, filter coefficient switching unit 33 is left guidance based on the traveling direction signal LrTS, turn right guide, the rectilinear guide / other guide Judge another. If it is a left turn guidance, the filter coefficient switching unit 33 reads the left turn filter coefficients W _11L and W _21L from the storage unit 32 and sets them in the FIR digital filters 16a _{11 to} 16a ₂₁ of the filter unit 16a. If
Turn right filter coefficients W _11R, read the W _21R from the storage unit 32 is set to the FIR type digital filter 16a ₁₁ ~16a _21, if linear guide, straight filter coefficient W _11C, the W _21C read from the storage unit 32 set to the FIR type digital filter 16a ₁₁ ~16a ₂₁ Te.

As a result, when guiding a left turn, the volume input to the left ear of the driver immediately becomes larger than the volume input to the right ear. Even if the driver cannot hear the guidance voice clearly due to noise, the left turn guidance is provided. Was easily recognized,
You can turn left correctly. In addition, when guiding a right turn, the volume input to the driver's right ear immediately becomes larger than the volume input to the left ear, and the driver turns right even if the driver cannot hear the guidance voice clearly due to noise. And you can turn right. In addition, straight guidance /
During other guidance, since the volume input to the left and right ears of the driver becomes equal and the voice guidance can be heard from the front, the driver can go straight ahead even if he / she cannot hear the guidance voice clearly due to noise.
It is possible to recognize that it was other guidance, and it is possible to continue straight traveling or running on the road.

(D) Third Embodiment of Navigation Voice Output Apparatus of the Present Invention FIG. 12 is a block diagram of a third embodiment of the navigation voice output apparatus of the present invention.
_The navigation device outputs _NV (= x (n)) and outputs a traveling direction signal LRTS indicating whether it is a right turn voice guide, a left turn voice guide, or a straight ahead voice guide. 17a and 17b are left and right speakers, 18 is an acoustic space, 31 is a driver, 41a and 41b are variable gain amplifiers, and 42 is whether the navigation sound is right turn guidance, left turn guidance, straight ahead guidance / other voice guidance. And a gain switching unit for switching the gains of the amplifiers 41a and 41b. Gain switcher 42, at the time of left turn guidance larger than the gain G _R of the amplifier 41a which is connected to the gain G _L of the amplifier 41b connected to the left speaker 17b to the right speaker 17a, at the time of right turn guidance right speaker 1
The gain G _R of the amplifier 41a that is connected to 7a larger than the gain G _L of the amplifier 41b connected to the left speaker 17b, an equal gain G _L, G _R at the time of linear guide / other assistance.

As a result, when guiding a left turn, the volume input to the left ear of the driver becomes larger than the volume input to the right ear. Even if the driver cannot hear the guidance voice clearly due to noise, the driver cannot turn left. You can easily recognize that you were there and make a right turn. Also, when guiding a right turn, the volume input to the driver's right ear becomes larger than the volume input to the left ear, and the driver turns right even if he / she cannot hear the guidance voice clearly due to noise. You can recognize and turn right. Also, during straight-ahead guidance / other guidance, since the volume input to the left and right ears of the driver is equal and voice guidance can be heard from the front, even if the driver cannot hear the guidance voice clearly due to noise, the vehicle goes straight / other. Can be recognized, and the vehicle can continue traveling straight or on a road.

In the above embodiment, the case where only the navigation audio signal is input to the left and right speakers 17a and 17b has been described. However, audio signals of the audio L channel / R channel are synthesized and input to these speakers. You can also. As described above, the present invention has been described with reference to the embodiments. However, the present invention can be variously modified in accordance with the gist of the present invention described in the claims, and the present invention does not exclude these.

[0045]

As described above, according to the present invention, the sound input to the left ear is made louder than the sound input to the right ear when the navigation sound is the left turn guidance, and the sound input to the right ear is provided for the right turn guidance. Since the input voice is set to be louder than the voice input to the left ear, even if the voice guidance cannot be heard clearly due to noise, the driver can recognize the direction in which the voice guidance was heard, and The vehicle can proceed. That is, even if the driver cannot clearly hear the voice guidance due to noise, the driver can correctly travel the vehicle in the navigation voice guidance direction.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram of an adaptive equalization system.

FIG. 2 is an explanatory diagram of characteristics set in a target response setting unit.

FIG. 3 is a configuration diagram of an adaptive filter.

FIG. 4 is a configuration diagram of a filter that generates a reference signal for adaptive processing (filtered reference signal).

FIG. 5 is a configuration diagram of a first embodiment of a navigation voice output device of the present invention.

FIG. 6 is a configuration diagram of a target response setting unit.

FIG. 7 is a configuration diagram of a filter for creating a filtered X signal.

FIG. 8 is a configuration diagram of an adaptive filter.

FIG. 9 is a specific example of an adaptive signal processing device.

FIG. 10 is an explanatory diagram of a method for determining a target signal output transfer characteristic.

FIG. 11 shows a second example of the navigation voice output device of the present invention.
FIG. 3 is a configuration diagram of an example.

FIG. 12 shows a third example of the navigation voice output device of the present invention.
FIG. 3 is a configuration diagram of an example.

[Explanation of symbols]

11 Navigation device 13 Target response setting unit 14a, 14b Microphone for detecting sound at first and second observation points 15a, 15b Operation unit 16 Adaptive signal processing device 16a Adaptive filter 17a . 17b speaker 19 transfer characteristic switching unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04S 1/00 H04S 1/00 K

Claims (3)

[Claims] 1. A navigation audio output device that receives a navigation audio signal and outputs navigation audio from at least two speakers arranged on the left and right sides of a vehicle interior. If the navigation audio is a left turn guidance, the navigation audio signal is input to the left ear. A volume control means for making the voice to be input to the right ear larger than the voice to be input to the right ear and for the right turn guidance to make the voice input to the right ear larger than the voice to be input to the left ear. Audio output device. 2. A navigation audio output device which receives a navigation audio signal and outputs navigation audio from at least two speakers arranged on the left and right sides of a vehicle cabin, wherein the left and right ear positions of the driver are used as observation points. A transfer characteristic for outputting a target signal at each observation point is set, and a target response setting unit that outputs a signal obtained by convolving the transfer characteristic with the navigation voice signal as a target signal at each observation point, Means for outputting an error signal, which is a difference between the detection signal detected at the above step and a target signal at each observation point. The navigation voice signal and the error signal at each observation point are input, and the power of each error signal is minimized. Performs adaptive signal processing to determine the coefficients of the adaptive filter, and performs navigation using the adaptive filter. An adaptive signal processor that inputs the signal obtained by filtering the audio signal to the left and right speakers. The target of each observation point is set so that the voice input to the left ear during the left turn guidance is larger than the voice input to the right ear Set the transfer characteristics for signal output in the target response setting section, and set the transfer characteristics for target signal output at each observation point to the target response so that the voice input to the right when guiding right turns is louder than the voice input to the left ear. A navigation sound output device comprising means for setting in a setting unit. 3. A navigation audio output device that receives a navigation audio signal and outputs navigation audio from at least two speakers arranged on the left and right sides of the vehicle interior. The first filter coefficient determined to be larger than the voice input to the left ear and the second filter coefficient determined so that the voice input to the right when guiding right turn is higher than the voice input to the left ear, Means for storing; a filter for setting the first and second filter coefficients as appropriate, performing a filtering process in accordance with the set filter coefficients on the input navigation audio signal, and inputting the filtered processing to the first and second speakers A first filter coefficient for a left turn is set in the filter at the time of a left turn, and a second filter section for a right turn at a right turn. A navigation sound output device comprising a filter coefficient switching means for setting a number to the filter.