KR20100095238A - Transmit signal level controller, and transceiving apparatus and method for controlling volume automatically using the same level controller - Google Patents

Abstract

PURPOSE: A transmission signal level controller automatically controlling level of a transmission signal according to a communication environment, a transceiving device automatically controlling volume using the same are provided to supply optimized call volume to a receiver without troublesome of operating separate volume button. CONSTITUTION: An energy calculating unit(110) calculates energy level of voice and silence section inputted from each of VAD(Voice Activity Detector). An environment determining unit(120) determines environment of a transmitter and a receiver. An auto gain control unit(130) automatically controls gain of a transmission signal. A transmit signal level control unit(140) automatically controls level of the transmission signal.

Description

Transmitter signal level controller, and transceiving apparatus and method for controlling volume automatically using the same level controller

The present invention relates to a mobile communication terminal, a two-way communication device and a communication environment, and in particular, in consideration of the communication environment of the receiver during a call, the receiver may adjust a transmission signal of the sender to allow the receiver to hear a more clearly received tone. It relates to a transmitting and receiving device and a method.

Mobile communication terminals, which are wireless telephones, are being rapidly used due to their convenience. Thus, service providers are looking for more users, such as phone books, games, short messages, the Internet, e-mail, and morning calls. Competitively developing terminals with convenient functions. As the quality of services provided by the mobile communication terminal is improved as the additional function of the mobile communication terminal, it has become a necessity of modern man recently. That is, anytime, anywhere can see the appearance of using a mobile communication terminal.

However, mobile communication terminals currently used generally do not recognize the incoming sound when the ambient noise of the sender and the receiver is severe because the sensitivity of the incoming sound varies depending on the noise environment of the sender and the receiver. There is this.

Accordingly, one of the methods for improving the quality of service provided by the mobile communication terminal provides a function of adjusting the call volume according to the surrounding situation to improve the call quality. However, the function of adjusting the call volume according to the surrounding environment has been inconvenient in that the user needs to directly adjust the call volume button (eg, side key) during a call. In addition, when using the call volume button, when both the sender volume and the receiver volume are increased or decreased at the same time and the sender environment and the receiver environment are contrasted with each other, one caller may feel uncomfortable or, in some cases, the received contents may be exposed to the outside of the caller. There are also possible problems.

On the other hand, a mobile communication terminal employing a function of removing noise at the receiver side during the reception has been developed, but there is a problem that it does not have a great effect when the ambient noise at the receiver side is severe.

On the other hand, the same problem occurs not only in the mobile communication terminal, but also in a public telephone installed in a noisy place, and in the case of a landline telephone in the home, the same problem occurs when it is noisy due to a conversation with a TV or neighbors.

The problem to be solved by the present invention is to eliminate the hassle of the operation of the call volume button as in the prior art, the transmission signal level controller and the volume using the controller can automatically provide a clear and high reception volume in consideration of the communication environment of the receiver It is to provide a self-regulating transceiver and method.

In order to solve the above problems, the present invention is an energy calculation unit for calculating the energy level of the voice (voice) and silence (silence) section input from each of the Voice Activity Detector (VAD) of the transmitter and the receiver; An environment determination unit to determine an environment of a receiver and a sender based on the calculated energy level; An automatic gain controller (AGC) for automatically adjusting gain of a transmission signal according to the determined environment; And a transmission signal level adjusting unit for automatically adjusting the level of the transmission signal by applying the adjusted gain.

In the present invention, the environment determining unit compares the energy level with various energy level thresholds, that is, Rx-CNLT, Tx-CSLT, and Tx-UCSLT, wherein the receiver side is a noisy environment and the sender side is normal. A first environment that is an environment, a second environment where the receiver side is a normal environment and the sender side is a secret call environment and a low transmission volume, a third environment where the receiver side is a noise environment and the sender side is a secret call environment and a low transmission volume Environment, and both the receiver side and the sender side can be classified into a fourth environment, which is a normal environment, and can be classified into a fifth environment when a transient transmission signal is generated by the sender due to an abnormality or characteristic of the transmission system or the influence of the noise environment around the sender. have.

In accordance with the above classification of the environment, the automatic gain controller, in the first environment, increases the gain of the transmission signal by a first gain value obtained by subtracting the Rx-CNLT from the noise energy level of the receiver side. In the case of the second environment, the Tx-CSLT increases the gain of the transmission signal by a second gain value obtained by subtracting the signal energy level of the sender side, and in the case of the third environment, In the case of the fourth environment, the gain of the transmission signal is not adjusted, and in the case of the fifth environment, the gain of the transmission signal is increased by the third gain value obtained by adding the first gain value and the second gain value. The gain of the transmission signal may be leveled down by a fourth gain value obtained by subtracting the Tx-UCSLT from the signal energy level of the transmitter side. In this case, compared to Tx-UCSLT for each gain level up, it is possible to limit the cause of the discomfort of the receiver due to excessive gain control adjustment.

In addition, the transmission signal level adjusting unit includes a dynamic range compressor (DRC) or a limiter. In the case of the DRC, the transmission signal level adjusting unit adjusts the level of the transmission signal for each signal component or for a predetermined subframe according to the adjusted gain. In the case of the limiter, the level of the transmission signal may be adjusted by preventing over-amplification of the over-amplification transmission signal or the sub-frame period signal.

The present invention also provides a receiver comprising a receiving VAD for dividing the received signal into a voice and a silence section for solving the above problems; Based on the transmission VAD for dividing the transmission signal into the voice and the silent section, and the energy level of the voice and the silent section inputted from the receiving VAD and the transmission VAD, the environment of the receiver side and the sender side is determined to determine the transmission signal. A transmission unit having a transmission signal level controller for adjusting a level; And a codec for converting the analog audio signal input from the input device into the digital transmission signal and outputting the digital audio signal to the transmitter. It provides a volume automatic transmission and reception device including; AD / DA Convertor).

In the present invention, the receiver decodes the received compressed signal, and a post processor that performs post-processing including equalization (EQ) and amplification (AMP) on the received signal. And a transmitter configured to perform a preprocessing including equalization, echo cancellation (EC), and amplification on the transmission signal output from the codec, based on the transmission VAD output. And a noise suppressor for controlling noise of the transmission signal, and an encoder for compressing and encoding the transmission signal for transmission or storage.

The present invention further provides a method for achieving the above object, the method comprising: preprocessing a digitalized transmission signal through a codec; Dividing the pre-processed transmission signal into a voice and silence section through a transmission VAD; Adjusting the level of the transmission signal based on an energy level of a speech and silence section input from a reception VAD and the transmission VAD; And encoding the transmission signal whose level is adjusted into a signal for transmission.

In the present invention, the step of controlling the noise of the transmission signal based on the output of the transmission VAD before the level adjustment step, wherein the level adjustment step, the voice input from the transmission VAD and the receiving VAD and Calculating an energy level for the silent section; Determining an environment of a receiver side and a sender side based on the calculated energy levels; Automatically adjusting a gain of the transmission signal according to the determined environment; And automatically adjusting the level of the transmission signal by applying the adjusted gain.

On the other hand, the environmental determination step, the first comparison step of comparing the noise energy level of the receiver side with the maximum noise level of the receiver side Rx-CNLT; And when the noise energy level of the receiver side is less than or equal to the Rx-CNLT, the signal energy level of the transmitter side is Tx-CSLT which is the minimum signal level of the transmitter side, and Tx which is the maximum signal level of the transmitter side. And a second comparing step of comparing with UCSLT. In addition, the environment determination step further includes an option on-off step, and in the case of the option on, performs both the first comparison step and the second comparison step, and in the case of the option off, only the first comparison step. It can also be done.

Transmission signal level controller according to the present invention and the automatic volume control transmission and reception apparatus and method using the controller by automatically adjusting and transmitting the level of the transmission signal according to the communication environment of the receiver side and the sender side, there is no separate volume button operation Allows the receiver to provide the optimal call volume without any burden. In addition, since the communication environment at the receiver side is already considered in the transmission signal, it is possible to provide a high reception quality to the receiver regardless of whether the communication environment at the receiver side is a noise environment or a general environment.

Furthermore, since the present invention considers the communication environment of the receiver side and the sender side, it is possible to overcome the inconvenience of the call due to the difference in the basic systemic volume control gains on the two communication devices of the sender and the receiver. Otherwise, even if it is necessary to change the volume of the talk, it is possible to provide a suitable volume to the receiver, thereby providing a high reception quality to the receiver.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, when a component is described as being connected to another component, it may be directly connected to another component, but a third component may be interposed therebetween. In addition, in the drawings, the structure or size of each component is exaggerated for convenience and clarity of explanation, and parts irrelevant to the description are omitted. Like numbers refer to like elements in the figures. It is to be understood that the terminology used is for the purpose of describing the present invention only and is not used to limit the scope of the present invention.

1 is a block structure diagram of a device for automatically adjusting and transmitting a volume according to an embodiment of the present invention.

Referring to FIG. 1, the apparatus for automatically adjusting the volume of the present embodiment includes a transmitter 1000, a receiver 2000, and a codec 3000.

The transmitter 1000 includes a Tx pre-processor (200), a transmitter Tx VAD (Voice Activity Detector, 300), a Tx noise suppressor (400), a transmitter signal level controller (Tx Signal Level Controller, 100). ) And a Tx encoder 500.

The Tx preprocessor 200 performs preprocessing including equalization (Equalization), echo cancellation (EC), and amplification on the transmission signal output from the codec 3000. The Tx VAD 300 divides the received signal into a voice and a silence section. The Tx noise suppressor 400 controls the noise of the transmission signal based on the output of the Tx VAD 300.

The transmission signal level controller 100 determines the environment of the receiver side and the transmitter side based on the energy levels of the voice and silent sections input from the Rx VAD 1200 on the receiving side and the Tx VAD 300 on the transmitting side. Adjust the level of the signal. That is, the transmission signal level controller 100 automatically adjusts the level of the transmission signal according to the communication environment of the receiver side and the sender side, that is, the noise level, thereby providing the optimal call volume to the receiver without the trouble of a separate volume button operation. Do it. The transmission signal level controller 100 will be described in more detail in the description with reference to FIG. 2.

The Tx encoder 500 compresses and encodes a transmission signal whose level is adjusted through the transmission signal level controller 100 into a signal for storage or transmission.

The receiver 2000 includes an Rx decoder 1100, a receiver Rx VAD 1200, an Rx noise suppressor 1300, and an Rx post processor 1400. The Rx decoder 1100 decodes the received received signal, and the receiving side VAD 1200 divides the decoded received signal into speech and silence sections. The noise suppressor 1300 is a component that may be selectively included and controls the noise of the received signal based on the output of the receiver Rx VAD 1200. That is, the noise of the received signal is appropriately removed. The Rx postprocessor 1400 performs post-processing including equalization (EQ) and amplification (AMP) on the received signal.

A codec AD / DA convertor 3000 converts an analog audio signal input from an input device, for example, a microphone, into a digital transmission signal and outputs the digital transmission signal to the transmitter 1000, and outputs the digital signal from the receiver. The received signal is converted into an analog voice signal and output to an output device such as a speaker SPK.

Volume control automatic transmission and reception apparatus according to the present embodiment includes a transmission signal level controller for automatically adjusting the level of the transmission signal according to the communication environment of the receiver side and the sender side, that is, the signal level on the transmitter side, to operate a separate volume button Allows the receiver to provide the best call volume without the hassle. That is, since the communication environment at the receiver side is already considered in the transmitted transmission signal, it is possible to provide a high reception quality to the receiver regardless of whether the communication environment at the receiver side is a noise environment or a general environment.

FIG. 2 is a block diagram illustrating the transmission signal level controller of FIG. 1 in more detail.

Referring to FIG. 2, the transmission signal level controller 100 according to the present embodiment includes an energy calculator 110, an environment determiner 120, an automatic gain controller 130, and a transmission signal level adjuster 140.

The energy calculation unit 110 calculates the noise energy level of the silent section from the Rx VAD 1200 of the receiver side and the Tx VAD 300 of the transmitter side. The energy calculation unit 100 also calculates the energy level of the voice section. Estimation or calculation of energy level in each section can be performed by efficiently selecting various signal processing mean or average techniques such as Long Term Peak Value, Average, RMS, L2 Norm according to each situation or need.

The environment determination unit 120 compares the energy levels of the receiver side and the transmitter side calculated by the energy calculation unit 110 with various energy level thresholds to determine the surrounding environment in various ways. For example, as energy level thresholds, the receiver comfortable noise level threshold (Rx-CNLT) on the receiver side, the transmitter comfortable signal level threshold (Tx-CSLT) on the sender side, And a transmitter uncomfortable signal level threshold (Tx-UCSLT) on the sender side. In this case, the CNLT, CSLT, and UCSLT may set the same value for both the transmitting and receiving devices, and may be relatively adjusted values according to internal and external amplification devices and setting values of each device.

By comparing these energy level thresholds with the receiver side or the sender side energy level, the environment where the receiver side is a noisy environment and the sender side is a normal environment as the first environment, the receiver side is a normal environment and the sender side is a secret call environment and transmission The environment with low volume as the second environment, the receiver side as a noisy environment, the sender side as a third environment, and the caller side as a third environment, and the receiver and sender sides as normal environments, a fourth environment. Can be distinguished. On the other hand, irrespective of the energy level threshold, an environment that is caused by a transmission system abnormality or characteristic, an influence of a noise environment around the sender, or a transient transmission signal generated by the sender may be classified into a fifth environment.

Here, Rx-CNLT may be the maximum noise level at the receiver side where the receiver can normally listen to the received signal, and Tx-CSLT may be the minimum signal level at the sender side where the receiver can normally listen to the received signal. In addition, Tx-UCSLT may be the maximum signal level of the sender side that the receiver cannot listen to the received signal normally. In addition, the secret call environment means that the signal level of the sender is lower than the energy level for the normal call due to the situation of the sender or the system abnormality, although the noise is not high.

The set noise levels may be set to Rx-CNLT as a first threshold, Tx-CSLT as a second threshold, and Tx-UCSLT as a third threshold.

With this definition of energy level thresholds, the first environment is when the noise energy level at the receiver side is greater than the first threshold value Rx-CNLT, and the second environment is at a second threshold where the signal energy level at the sender side is greater than the second threshold. It is time to be smaller than the value (Tx-CSLT). In addition, the third environment is when the signal energy level of the sender side is greater than the third threshold value Tx-UCSLT, and the fourth environment is the first to third environment where the signal or noise energy levels of the receiver side and the sender side are preceded. It is time to belong to other range.

On the other hand, the environment determination unit 120 has an option on-off (On) Off function (Previous to the second and third environment is not separately determined, may be divided into only the first and fourth environment. That is, in the case of the option off, it is determined only whether the noise energy level of the receiver side is greater than the first threshold value Rx-CNLT, and when it is large, it is determined as the first environment, and when it is less than or equal to the fourth environment which is the normal environment. To judge. In conclusion, in the case of the option off, it means that the second environment and the third environment are also determined as the fourth environment which is a normal environment.

The automatic gain controller 130 automatically adjusts the gain of the transmission signal according to each environment through the environment determination unit 120. That is, depending on each environment, the level up or down of the gain is calculated through the following equations.

AGC control level of the first environment = Rx-NL-Rx-CNLT = Tx-SSLU1 ..... (1)

AGC control level in the second environment = Tx-CSLT-Tx-SL = Tx-SSLU2 .......... Equation (2)

AGC control level of the third environment = Tx-SSLU1 + Tx-SSLU2 = Tx-SSLU3 ...... Equation (3)

AGC control level in the fifth environment = Tx-SL-Tx-UCSLT = Tx-SSLD .......... Equation (4)

Here, Rx means the receiver side, Tx means the sender side. In addition, SL is an abbreviation of signal level of speech section, NL is an abbreviation of noise level of silence section, SSLU is an abbreviation of Signal Scale Level UP, and SSLD is Abbreviation for signal scale level down.

The meaning of each expression is as follows. That is, Equation (1) means that the gain of the transmission signal is increased by the gain value obtained by subtracting the first threshold value Rx-CNLT from the noise energy level of the receiver side when it is determined as the first environment. Equation (2) means that in the second environment, the gain of the transmission signal is increased by the gain value obtained by subtracting the signal energy level of the transmitter from the second threshold value Tx-CSLT. In addition, in the case of the third environment, equation (3) means that the gain of the transmission signal is increased by the gain value obtained by adding the Tx-SSLU1 and the Tx-SSLU2 calculated in the first environment and the second environment. (4) means that in the fifth environment, the gain of the transmission signal is lowered by the gain value obtained by subtracting the third threshold value Tx-UCSLT from the signal energy level of the transmitter side. In this case, compared to the third threshold value Tx-UCSLT in the case of each gain level up, it is possible to limit the occurrence of discomfort of the receiver due to excessive gain adjustment adjustment. On the other hand, since the fourth environment is a normal environment, the gain of the transmission signal is not adjusted.

In addition, as described above, the environment determination unit 120 includes an option on-off function, and when the option is off, the second environment and the third environment are determined as the fourth environment, which is a normal environment. Do not adjust the gain of the transmission signal.

The transmission signal level adjusting unit 140 automatically adjusts the energy level of the transmission signal based on the gain values previously calculated by the automatic gain controller 130. The transmission signal level control unit 140 may include a dynamic range compressor (DRC) or a limiter (DRC) for gain control without distortion of the signal. If the DRC is included, the transmission signal according to the adjusted gain The level of the transmission signal may be adjusted for each signal component or in units of a predetermined subframe. On the other hand, when the limiter is included, the level of the transmission signal may be adjusted by performing only a function of preventing over-amplification for the over-amplification transmission signal or the sub-frame period signal. On the other hand, even when the gain is not adjusted, the transmission signal level automatic adjustment unit 140 may of course adjust the level to the transmission signal suitable for the call for each signal component or in a predetermined sub-frame unit.

3 is a graph showing the division of the speech section and the silent section by the VAD.

Referring to FIG. 3, the VAD distinguishes between a voice section and a silence section with respect to a voice signal, that is, a transmission signal or a reception signal. As such, the VAD classifies the energy level of noise included in the voice signal. This is for convenience of calculation. That is, the energy level in the silent section can be seen as the energy level of the noise included in the speech section. In the figure, V1 to V4 are voice sections, and S1 to S3 between them are silent sections. Here, although the energy level of the silent section is indicated as almost zero, it is obvious that some energy level exists, and it is obvious that the energy level of the silent section will be increased in a noisy environment where the surrounding environment is noisy.

4 is a graph showing the positions of noise level thresholds used in the present invention with respect to normal speech energy levels.

Referring to FIG. 4, in general, if a section of a normal volume energy level for transmission and reception is referred to as L ₁ to L ₂ , and a maximum energy level of volume is referred to as L _M , the aforementioned first threshold value Rx-CNLT. a second energy level of the threshold value of the threshold value (Tx-CSLT), and the third threshold value (Tx-UCSLT) is L _{Rx respectively} itgetda be represented by _UCS-CN, L _Tx-CS, and L _Tx. In general, the noise on the receiver side directly affects the receiver, so L _{Rx - CN} is _replaced by L _{Tx - CS.} It is desirable to set lower. However, these thresholds can be set differently because the user can define and use them arbitrarily according to the situation. It may also be set higher than L ₁ . On the other hand, L _{Tx - UCS} is generally larger than L ₂ because it represents a case where the volume on the sender's side is so large that the receiver is hard to hear or is awkward. For reference, L ₁ may be 25dB, L ₂ may be 60dB, and L _M may be 96dB for a 16-bit signal, but may vary according to an external amplifier in a system of a communication device.

5 is a flowchart illustrating a method for automatically adjusting volume control according to another embodiment of the present invention. For convenience of understanding, the following description will be made with reference to FIG. 1.

Referring to FIG. 5, in the method for automatically adjusting the volume of the present embodiment, first, voice is input through an input device such as a microphone (MIC) (S100). Next, the input voice signal is converted into a digital signal through the codec 3000 (S200). The transmitted signal converted into a digital signal is pre-processed in the Tx preprocessor 200 including equalization (EQ), echo cancellation (EC), and amplification (S300). The transmission signal on which the preprocessing has been performed is divided into a speech section and a silent section through the transmitting side Tx VAD 300 (S400), and the Tx noise suppressor 400 transmits the signal based on the output of the Tx VAD 300. Reducing or eliminating the energy of the noise contained in the appropriately controls the noise (S500).

In the transmission signal whose noise is controlled, the signal level is appropriately adjusted by the transmission signal level controller 100 (S600). This signal level adjustment is performed based on the output signals of the transmitting side Tx VAD 300 and the receiving side Rx VAD 1200. Signal level adjustment is described in more detail with reference to FIG. 6. The level-adjusted transmission signal is encoded into a signal for storage or transmission (S700).

The automatic volume control transmission / reception method according to the present invention automatically adjusts and transmits a level of a transmission signal according to a communication environment of a receiver side and a transmitter side, thereby providing an optimal call volume to a receiver without the trouble of a separate volume button operation. To be. In addition, the communication environment at the receiver side is considered to provide a high reception quality to the receiver regardless of whether the communication environment at the receiver side is a noisy environment or a general environment. Furthermore, considering the communication environment of the receiver and the sender side, it is possible to overcome the inconvenience of the call caused by the difference of the basic systemic volume control gains between the sender and the receiver. Even if it is necessary to provide a change in the volume, a suitable volume is provided to the receiver to provide a high reception quality to the receiver. In addition, the method of the present invention can be configured through the above-described automatic level adjustment method using not only the signal level in the time domain but also the frequency signal level in the frequency domain.

6 is a flowchart illustrating the transmission signal level adjusting step of FIG. 5 in more detail. For convenience of understanding, the following description will be made with reference to FIG. 2.

Referring to FIG. 6, in the transmitting signal level adjusting step (S600), first, the energy calculating unit 110 calculates energy for the speech section and the silent section based on the output signals of the receiving side Rx VAD and the transmitting side Tx VAD. (S610). As described above, the energy calculation may be performed by efficiently selecting various signal processing mean or average techniques such as Long Term Peak Value, Average, RMS, and L2 Norm according to each situation or need. After the energy calculation, the environment determiner 120 first compares whether the noise level Rx-NL at the receiver side is greater than the first threshold value Rx-CNLT (S620).

When the noise level on the receiver side is greater than the first threshold value Rx-CNLT, the process proceeds to the gain adjusting step S630 by the automatic gain controller 130. On the other hand, if the receiver noise level is less than or equal to the first threshold value Rx-CNLT, it is determined whether the option is on or off (S640). If the option is off, the transmission signal level is automatically adjusted. In step S660, if the option is turned on, it is again determined whether the signal energy level of the sender is smaller than the second threshold value Tx-CSLT or greater than the third threshold value Tx-UCSLT. (S650). If the signal energy level of the sender side is smaller than the second threshold value Tx-CSLT or greater than the third threshold value Tx-UCSLT, the process proceeds to the gain adjusting step S630. When the signal energy level is greater than the second threshold value Tx-CSLT and less than the third threshold value Tx-UCSLT, the transmission signal level automatic adjustment step S660 is performed.

In the gain adjusting step S630, the gain of the transmission signal is adjusted according to each environment. That is, when the noise level of the receiver side is greater than the first threshold value Rx-CNLT, the gain is adjusted by Equation (1), and the signal energy level of the transmitter side is greater than the second threshold value Tx-CSLT. If it is small, the gain is adjusted by equation (2), and when the signal energy level of the sender is larger than the third threshold value Tx-UCSLT, the gain is adjusted by equation (3). On the other hand, even when the noise energy level at the receiver side is smaller than the first threshold value Rx-CNLT, the gain may be adjusted by Equation (4) when a transient transmission signal is generated by a transmission system error or characteristic or by the sender. have.

In the transmission signal level automatic adjustment step (S660), the level of the transmission signal is adjusted through a dynamic range compressor (DRC) or a limiter (Limiter). When adjusting through the DRC, each signal component or predetermined according to the adjusted gain. The level of the transmission signal may be adjusted in units of subframes, and when adjusting through the limiter, the level of the transmission signal may be adjusted by preventing over-amplification of the over-amplification transmission signal or the sub-frame period signal. On the other hand, even when there is no gain adjustment, the step of automatically adjusting the transmission signal level can be adjusted to the level of the transmission signal suitable for the call for each signal component or in a predetermined subframe unit.

So far, the present invention has been described with reference to the embodiments shown in the drawings, which are merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. . Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a block structure diagram of a device for automatically adjusting and transmitting a volume according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating the transmission signal level controller of FIG. 1 in more detail.

3 is a graph showing the division of the speech section and the silent section by the VAD.

4 is a graph showing the positions of noise level thresholds used in the present invention with respect to normal speech energy levels.

5 is a flowchart illustrating a method for automatically adjusting volume control according to another embodiment of the present invention.

6 is a flowchart illustrating the transmission signal level adjusting step of FIG. 5 in more detail.

Claims (20)

An energy calculator configured to calculate an energy level of a voice and silence section input from a voice activity detector (VAD) of each of the transmitter and the receiver; An environment determination unit to determine an environment of a receiver and a sender based on the calculated energy level; An automatic gain controller (AGC) for automatically adjusting gain of a transmission signal according to the determined environment; And And a transmission signal level controller for automatically adjusting the level of the transmission signal by applying the adjusted gain. According to claim 1, The environmental determination unit, The energy level is compared with the first threshold value Rx-CNLT on the receiver side, the second threshold value Tx-CSLT on the sender side, and the third threshold value Tx-UCSLT on the sender side, A first environment in which the receiver side is a noisy environment and the sender side is a normal environment, a second environment in which the receiver side is a normal environment and the sender side is a secret call environment, the receiver side is a noise environment and the sender side is a secret call The third environment, which is an environment, and the fourth environment, in which both the receiver side and the sender side are normal environments, A transmission signal level controller characterized in that it is divided into a fifth environment when a transmission system error or characteristic or a transient transmission signal is generated by the sender. The method of claim 2, The first threshold value Rx-CNLT is the maximum noise level at the receiver side at which the receiver can normally listen to the received signal, and the second threshold value Tx-CSLT is the receiver listening to the received signal normally. The minimum signal level at the sender side, the third threshold value Tx-UCSLT is the maximum signal level at the sender side at which the receiver cannot normally listen to the received signal, The first environment is when the noise energy level of the receiver side is greater than the first threshold value Rx-CNLT, and the second environment has a signal energy level of the sender side of the second threshold value Tx-CSLT. The third environment is when the signal energy level of the sender side is greater than the third threshold value Tx-UCSLT, and the fourth environment is the energy level of the receiver side and the sender side. A transmission signal level controller characterized by an environment in a range other than three environments. The method of claim 2, The automatic gain controller, In the case of the first environment, the gain of the transmission signal is increased by the first gain value obtained by subtracting the first threshold value Rx-CNLT from the noise energy level of the receiver side. In the case of the second environment, the gain of the transmission signal is increased by a second gain value obtained by subtracting the signal energy level of the transmitter side from the second threshold value Tx-CSLT. In the third environment, the gain of the transmission signal is leveled up by a third gain value obtained by adding up the first gain value and the second gain value. In the case of the fourth environment, the gain of the transmission signal is not adjusted. In the case of the fifth environment, a transmission signal level characterized in that the gain of the transmission signal is lowered by a fourth gain value obtained by subtracting the third threshold value Tx-UCSLT from the signal energy level of the transmitter. controller. The method of claim 2, The environmental determination unit, The second environment and the third environment are determined only when the option is turned on through the option on-off function, and when the option is turned off, the second environment and the third environment return to the fourth environment. Judged, And the automatic gain controller does not adjust the gain of the transmission signal with respect to the second and third environments when the fourth environment or the option is off. According to claim 1, The transmission signal level adjusting unit includes a dynamic range compressor (DRC) or a limiter, In the case of the DRC, the level of the transmission signal is adjusted for each signal component or for a predetermined subframe according to the adjusted gain. And the limiter adjusts the level of the transmission signal by preventing over-amplification of the over-amplification transmission signal or sub-frame period signal. A receiving unit having a receiving VAD for dividing the received signal into voice and silence sections; The level of the transmission signal is determined by determining the environment of the receiver side and the transmitter side based on the transmission VAD which divides the transmission signal into a speech and silence section, and the energy level of the speech and silence section inputted from the reception VAD and the transmission VAD. A transmission unit having a transmission signal level controller for controlling the control unit; And A codec for converting an analog audio signal input from an input device into the digital transmission signal and outputting the digital audio signal to the transmitter. Volume automatic transmission and reception device comprising a. The method of claim 7, wherein The receiver includes a decoder to decode the received signal, and a post processor to perform post-processing including equalization (EQ) and amplification (AMP) on the received signal. The transmitter may include a preprocessor configured to perform preprocessing, including equalization, echo cancellation (EC), and amplification, on the transmission signal output from the codec, and based on the transmission VAD output. And a noise suppressor for controlling noise, and an encoder for compressing and encoding the transmission signal for transmission or storage. The method of claim 7, wherein The transmission signal level controller, An energy calculator configured to calculate energy levels of the voice and silent sections inputted from the received VAD and the transmitting VAD; An environment determination unit that determines an environment of the receiver side and the sender side based on the calculated energy level; An automatic gain controller (AGC) for automatically adjusting gain of the transmission signal according to the determined environment; And And a transmission signal level adjusting unit for automatically adjusting the level of the transmission signal by applying the adjusted gain. The method of claim 9, The environmental determination unit, A first environment when the noise energy level at the receiver side is greater than a first threshold value Rx-CNLT, a second environment when the signal energy level at the transmitter side is less than a second threshold value Tx-CSLT, and the sender A third environment when the signal energy level on the side is greater than a third threshold value Tx-UCSLT, and a fourth environment when the energy levels on the receiver side and the sender side are in a range other than the first, second, and third environments. Separated by A volume automatic transmission and reception device, characterized in that it is classified into a fifth environment when an excessive transmission signal is generated on the sender side by a transmission system error or characteristic or by the sender. The method of claim 10, The automatic gain controller, In the case of the first environment, the gain of the transmission signal is increased by the first gain value obtained by subtracting the first threshold value Rx-CNLT from the noise energy level of the receiver side. In the case of the second environment, the gain of the transmission signal is increased by a second gain value obtained by subtracting the signal energy level of the transmitter side from the second threshold value Tx-CSLT. In the third environment, the gain of the transmission signal is leveled up by a third gain value obtained by adding up the first gain value and the second gain value. In the case of the fourth environment, the gain of the transmission signal is not adjusted. In the case of the fifth environment, the volume of the transmission signal is automatically adjusted by decreasing the gain of the transmission signal by a fourth gain value obtained by subtracting the third threshold value Tx-UCSLT from the signal energy level of the transmitter. Transceiver. The method of claim 10, The environmental determination unit, The second environment and the third environment are determined only when the option is turned on through the option on-off function, and when the option is turned off, the second environment and the third environment are determined as the fourth environment, And the automatic gain controller does not adjust the gain of the transmission signal with respect to the second and third environments when the fourth environment or the option is off. Preprocessing the digitalized transmission signal through a codec; Dividing the pre-processed transmission signal into a voice and silence section through a transmission VAD; Adjusting a level of the transmission signal based on an energy level of a speech and silence section input from a reception VAD and the transmission VAD; And And encoding the transmission signal whose level is adjusted into a signal for transmission. The method of claim 13, The level adjustment step, Calculating energy levels for the voice and silent sections inputted from the transmitting VAD and the receiving VAD; Determining an environment of a receiver side and a sender side based on the calculated energy levels; Automatically adjusting a gain of the transmission signal according to the determined environment; And Automatically adjusting the level of the transmission signal by applying the adjusted gain; volume automatic transmission and reception method comprising a. 15. The method of claim 14, The environmental determination step, A first comparing step of comparing the noise energy level of the receiver side with a first threshold value Rx-CNLT which is the maximum noise level of the receiver side; And When the noise energy level of the receiver side is less than or equal to the first threshold value Rx-CNLT, the signal energy level of the transmitter side is the second threshold value Tx-CSLT which is the minimum signal level of the transmitter side. And a second comparing step of comparing with a third threshold value Tx-UCSLT, which is a maximum signal level of the sender side. The method of claim 15, In the gain automatic adjustment step, The noise energy level of the receiver side is greater than the first threshold value Rx-CNLT, or the signal energy level of the transmitter side is smaller than the second threshold value Tx-CSLT or the third threshold value ( Tx-UCSLT), the volume control automatic transmission and reception method, characterized in that for adjusting the gain of the transmission signal. The method of claim 16, In the gain automatic adjustment step, When the noise energy level of the receiver side is greater than the first threshold value Rx-CNLT, the first gain value is obtained by subtracting the first threshold value Rx-CNLT from the noise energy level of the receiver side. Level up the gain of the transmitted signal, When the signal energy level of the sender side is smaller than the second threshold value Tx-CSLT, the second gain value is subtracted from the second threshold value Tx-CSLT by the second gain value. Level up the gain of the transmitted signal, When the noise energy level of the transmitter side is greater than the third threshold value Tx-UCSLT, the gain of the transmission signal is increased by a third gain value obtained by adding up the first gain value and the second gain value. Volume automatic transmission and reception method characterized in that. The method of claim 15, In the gain automatic adjustment step, When the noise energy level on the receiver side is smaller than the first threshold value Rx-CNLT, and when a transient transmission signal is generated by a transmission system error or characteristic or by the sender, the signal energy level on the sender side is determined. And decreasing the gain of the transmission signal by a fourth gain value by subtracting a third threshold value (Tx-UCSLT). The method of claim 15, The environmental determination step further includes an option on-off step, If the option is on, both the first comparison step and the second comparison step are performed. If the option is off, the automatic volume control transmission and reception method, characterized in that for performing only the first comparison step. 15. The method of claim 14, In the step of adjusting the level of the transmission signal Adjust the level of the transmission signal through a dynamic range compressor (DRC) or limiter (Limiter), When adjusting through the DRC, the level of the transmission signal is adjusted for each signal component or for a predetermined subframe according to the adjusted gain. When adjusting through the limiter, the automatic volume control transmission and reception method, characterized in that for adjusting the level of the transmission signal by preventing over-amplification for the over-amplification transmission signal or sub-frame period signal.

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