CN102026058A - Drive-by-wire earphone device and design method thereof - Google Patents

Abstract

The invention provides a drive-by-wire earphone device which comprises a signal wire and a drive-by-wire device connected in series on the signal wire, wherein at least two omnidirectional microphones and a signal processor electrically connected with the omnidirectional microphones are arranged in the drive-by-wire device, and the signal processor comprises a delay unit for delaying signals and a subtraction unit for superposing signals; and the omnidirectional microphones are sequentially arranged from top to bottom along the signal wire and are electrically connected, and the omnidirectional microphones are arranged at a certain interval. The invention also provides a design method based on the drive-by-wire earphone device. The drive-by-wire earphone device has a noise-canceling function, and the speech quality is satisfactory.

Description

Line control earphone device and method for designing thereof

[technical field]

The present invention relates to a kind of wire-controlled apparatus and method for designing thereof, relate in particular to a kind of line control earphone device and method for designing thereof.

[background technology]

Along with the acoustic product in the acoustics development of science and technology, the particularly communications field, as mobile phone, computer etc.For busy businessperson, that fears the personage of radiation effect health and pursue trend extremely dazzles gang, and they pursue more and more to the line control earphone device that is used on the acoustic product especially.Except the pursuit of the product function of correlation technique, people require also more and more higher to the communication effect of product.

Yet, the line control earphone device earphone of correlation technique and the wire-controlled apparatus that is connected electrically on the earphone, described wire-controlled apparatus is provided with a microphone.When people use the line control earphone device of correlation technique to converse, have bigger ambient noise, thereby influenced speech quality.

Therefore, being necessary to propose a kind of new line control earphone in fact addresses the above problem.

[summary of the invention]

The technical problem that the present invention need solve provides a kind of de-noising function that has, the line control earphone device that speech quality is good.

According to above-mentioned technical problem, designed a kind of line control earphone device, its objective is such realization: a kind of line control earphone device, it comprises that holding wire and polyphone are connected on the wire-controlled apparatus on the described holding wire.Wherein, the signal processor that is provided with at least two omni-directional microphone and is electrically connected with described omni-directional microphone in the described wire-controlled apparatus, described signal processor comprise delay cell that makes signal delay and the subtrator that signal is superposeed.Described omni-directional microphone is arranged in order from top to bottom and is electrically connected along the direction of holding wire, and separated by a distance between the described omni-directional microphone.

The present invention also provides a kind of as above-mentioned line control earphone Design of device method, and this method comprises the steps:

Steps A, provide a sound source, described sound source produces plane wave signal;

One earphone is provided, and described earphone is connected on the described holding wire;

Two omni-directional microphone are provided, and it is respectively first microphone and second microphone and described first microphone and the anti-phase serial connection of second microphone and forms the differential type microphone array jointly;

Step B, described second microphone is done to postpone to handle to the response of described plane wave signal, and make and equal described plane wave signal is transferred to described second microphone from described first microphone time its time of delay by described delay cell.

Step C, described first microphone and second microphone are exported first sensitivity and second sensitivity respectively after described plane wave signal is responded, subtrator by described signal processor is first sensitivity and second sensitivity processing that subtracts, thereby obtains the total sensitivity of described differential type microphone array.

Preferably, described first microphone and described second microphone 1.5CM of being separated by, described second microphone is made as 4.4 * 10 to the response time of described plane wave signal ^-5S.

Compare with correlation technique, line control earphone device of the present invention has the de-noising function, has guaranteed use line control earphone device calling quality.

[description of drawings]

Fig. 1 is the structural representation of line control earphone device of the present invention.

Fig. 2 is the schematic diagram of line control earphone device of the present invention and method for designing thereof.

Fig. 3 is a line control earphone device directive property curve chart of the present invention.

[embodiment]

The invention will be further described below in conjunction with drawings and embodiments.

As shown in Figure 1, a kind of line control earphone device 1, it comprises that holding wire 2 and polyphone are connected on the wire-controlled apparatus 3 on the holding wire 2.Wherein, the signal processor 32 that is provided with at least two omni-directional microphone 31 in the wire-controlled apparatus 3 and is electrically connected with omni-directional microphone 31, signal processor 32 comprise delay cell 321 that makes signal delay and the subtrator 322 that makes the signal stack.Omni-directional microphone 31 is arranged in order from top to bottom and is electrically connected along the direction of holding wire 2, and separated by a distance between the omni-directional microphone 31.

The present invention also provides a kind of method for designing of as above-mentioned line control earphone device 1, and this method comprises the steps:

Steps A, provide a sound source (not shown), sound source produces plane wave signal, and plane wave signal is made as s (t);

One earphone 5 is provided, and earphone 5 is connected on the holding wire 2;

Two omni-directional microphone 31 are provided, it is respectively first microphone 311 and second microphone 312 and first microphone 311 and second microphone, 312 anti-phase serial connections and forms the differential type microphone array jointly, and anti-phase serial connection can be so that the signal that two omni-directional microphone 21 are produced forms the subtraction effect of signal when stack.

Step B, the principle that equates according to electric delay and sound lag, by delay cell 321 response of 312 pairs of plane wave signals of second microphone is done to postpone to handle, and make and equal described plane wave signal is transferred to second microphone 312 from first microphone 311 time its time of delay.

Export first sensitivity and second sensitivity respectively after step C, first microphone 311 and 312 pairs of plane wave signal responses of second microphone, subtrator 322 by signal processor 32 is first sensitivity and second sensitivity processing that subtracts, thereby obtains the total sensitivity of differential type microphone array.

Concrete, in the execution mode, two omni-directional microphone 31 to be arranged the back form the differential type microphone array, the open circuit sensitivity of first microphone 311 and second microphone 312 all is made as E, and output sensitivity is made as e respectively ₁And e ₂By delay cell 321 response of 312 pairs of plane wave signals of second microphone is done to postpone to handle, be made as T the time of delay of its output response, and plane wave signal is made as t1 from the transmission time of first microphone, 311 to second microphones 312, and the output sensitivity of differential type microphone array is made as e ₀, its open circuit sensitivity is E ₀, first microphone 311 and second microphone, 312 standoff distances are made as d.D=1.5CM is set in the present embodiment, then has:

$\mathrm{<figure-callout\; id="1"\; label="t"\; filenames="HDA0000041404400000011.png"\; state="\{\{state\}\}">t</figure-callout>}1=\frac{d}{c_0}=4.4\&times;{10}^{-5}\left(s\right),$ c ₀Be the velocity of sound.

Therefore, make T=t1 according to the principle needs of sound lag and electric delay, then T=4.4 * 10 ^-5(s).

The plane wave signal that described sound source is provided is made as s (t)=P _aE ^{J (ω t-kx)}, wherein ω is the plane wave frequency, k is a wave number,

c ₀Be the velocity of sound, t is the transmission time of plane wave signal, and x is the distance of omni-directional microphone 31 and sound source (not shown).Certainly, first microphone 311 and second microphone, 312 standoff distance d also can be made as other value, but principle is the same.

As shown in Figure 2, plane wave is transferred to first microphone 311 and second microphone 312, the direction of its transmission is the θ angle with first microphone 311 and being connected of second microphone 312, and then the acoustic pressure that receives of first microphone 311 is made as P ₁(t),

$P_1\left(t\right)=P_a\&CenterDot;e^{j(\mathrm{\&omega;t}-{\mathrm{kx}}_1)}$

Its corresponding output sensitivity is e ₁,

$\left|{\mathrm{<figure-callout\; id="1"\; label="e"\; filenames="HDA0000041404400000011.png"\; state="\{\{state\}\}">e</figure-callout>}}_1\right|=E\&CenterDot;|P_a\&CenterDot;e^{j(\mathrm{\&omega;t}-{\mathrm{kx}}_1)}|$

Second microphone connects 312 sound pressure levels of receiving and is made as P ₂(t),

$P_2\left(t\right)=P_a\&CenterDot;e^{j(\mathrm{\&omega;t}-k(x_1+d\cos \mathrm{\&theta;}))}$

Its corresponding output sensitivity is e ₂,

$\left|{\mathrm{<figure-callout\; id="2"\; label="e"\; filenames="HDA0000041404400000011.png"\; state="\{\{state\}\}">e</figure-callout>}}_2\right|=E\&CenterDot;|P_a\&CenterDot;e^{j[\mathrm{\&omega;}(t-T)-k(x_1+d\cos \mathrm{\&theta;})]}|$

Therefore, the output sensitivity of differential type microphone array is e ₀,

$\left|e_0\right|=\left|{\mathrm{<figure-callout\; id="1"\; label="e"\; filenames="HDA0000041404400000011.png"\; state="\{\{state\}\}">e</figure-callout>}}_1\right|-\left|{\mathrm{<figure-callout\; id="2"\; label="e"\; filenames="HDA0000041404400000011.png"\; state="\{\{state\}\}">e</figure-callout>}}_2\right|=E\&CenterDot;|P_a\&CenterDot;e^{j(\mathrm{\&omega;t}-{\mathrm{kx}}_1)}(1-e^{-j(\mathrm{\&omega;T}+\mathrm{kd}\cos \mathrm{\&theta;})})|$

The open circuit sensitivity of differential type microphone array is E ₀:

$E_0=\left|\frac{e_0}{{\mathrm{<figure-callout\; id="1"\; label="P"\; filenames="HDA0000041404400000011.png"\; state="\{\{state\}\}">P</figure-callout>}}_1}\right|=E\&CenterDot;|1-e^{-j(\mathrm{\&omega;T}+\mathrm{kd}\cos \mathrm{\&theta;})}|$

Can draw open circuit sensitivity linear increase that described omni-directional microphone forms the differential type microphone array by following formula along with the increase of the frequencies omega of plane wave;

The above-mentioned derivation principle of foundation can draw the directive property of differential type microphone array, and it is made as D (θ),

$D\left(\mathrm{\&theta;}\right)=\frac{E_0\left(\mathrm{\&theta;}\right)}{E_0\left(0\right)}=\frac{T+d\cos \mathrm{\&theta;}/c_0}{T+d/c_0}=\frac{T}{T+d/c_0}+(1-\frac{T}{T+d/c_0})\cos \mathrm{\&theta;}$

Order Then: D (θ)=A+ (1-A) cos θ,

According to electric delay and the equal principle of sound lag, when

When being A=1/2, the directive property of differential type microphone array is:

$D\left(\mathrm{\&theta;}\right)=\frac{1}{2}(1+\cos \mathrm{\&theta;})$

As shown in Figure 3, can draw the angular range of the directive property of differential type microphone array, its directive property is the strongest when voice signal is transferred to the differential type microphone array with θ=90 a ° direction, just the response effect of 1 pair of voice signal of line control earphone device is best, along with the increase of θ or reduce, the directive property of differential type microphone array more and more a little less than, to the response of voice signal also more and more a little less than, thereby reached de-noising effect.

Compare with correlation technique, control Headphone device of the present invention is because be provided with differential type microphone array and the signal processor that two omni-directional microphone form, by signal processor one of them work in the omni-directional microphone is postponed to handle, make the differential type microphone array have directive property, and then reach de-noising effect.

Above-described only is embodiments of the present invention, should be pointed out that for the person of ordinary skill of the art at this, under the prerequisite that does not break away from the invention design, can also make improvement, but these all belongs to protection scope of the present invention.

Claims (3)

1. line control earphone device, it comprises that holding wire and polyphone are connected on the wire-controlled apparatus on the described holding wire, it is characterized in that: the signal processor that is provided with at least two omni-directional microphone and is electrically connected in the described wire-controlled apparatus with described omni-directional microphone, described signal processor comprises the delay cell that makes signal delay and makes the subtrator of signal stack, described omni-directional microphone is arranged in order from top to bottom and is electrically connected along the direction of holding wire, and separated by a distance between the described omni-directional microphone.

2. line control earphone Design of device method as claimed in claim 1, it is characterized in that: this method comprises the steps:

Steps A, provide a sound source, described sound source produces plane wave signal;

One earphone is provided, and described earphone is connected on the described holding wire;

Two omni-directional microphone are provided, and it is respectively first microphone and second microphone and described first microphone and the anti-phase serial connection of second microphone and forms the differential type microphone array jointly;

Step B, described second microphone is done to postpone to handle to the response of described plane wave signal, and make and equal described plane wave signal is transferred to described second microphone from described first microphone time its time of delay by described delay cell;

Step C, described first microphone and second microphone are exported first sensitivity and second sensitivity respectively after described plane wave signal is responded, subtrator by described signal processor is first sensitivity and second sensitivity processing that subtracts, thereby obtains the total sensitivity of described differential type microphone array.

3. line control earphone Design of device method according to claim 2 is characterized in that: described first microphone and described second microphone 1.5CM of being separated by, described second microphone is made as 4.4 * 10 to the response time of described plane wave signal ^-5S.

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