JP2005217542A - Interphone system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make an interphone system small in size and low in cost by reducing the number of components. <P>SOLUTION: A DSP 22 of a master unit A includes: a variable gain amplifier 22b for amplifying notice tone data generated by a notice tone generating section 5; a tone volume adjustment section 22c for adjusting the tone volume of a notice tone by adjusting the gain of the variable gain amplifier 22b; and a superimposing section 22d for summating the notice tone data whose tone volume is adjusted to a digital received signal outputted from a speech processing section 4 to superimpose both the data and the signal. That is, since the notice tone data are superimposed on the digital speech signal (received signal) and thereafter the superimposed signal is converted into an analog signal, a D/A converter exclusively used for the notice tone data is not needed and the number of components is reduced more than heretofore, thereby making the interphone system small in size and low in cost. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an interphone device that constitutes an interphone system together with an interphone cordless handset.

  Conventionally, an intercom cordless handset installed outside a house (such as a front door) with a microphone and a speaker, and an interphone device (interphone main unit and sub-base unit) installed inside a house with a microphone and a speaker. An intercom system that enables two-way loudspeaking calls is provided.

  FIG. 6 is a block diagram showing a conventional interphone master unit (hereinafter abbreviated as a master unit) of the type disclosed in Patent Document 1. In FIG. This master unit connects a signal line L1 between a microphone 1 and a speaker 2, a 2-wire to 4-wire conversion unit 3 that performs 2-wire to 4-wire conversion, and an interphone handset (hereinafter abbreviated as a handset) C. A call processing unit 4 that performs a process for realizing a two-way loudspeaking call via the mobile phone, and a call sound output from the speaker 2 in response to a call from the handset C and a signal line to the handset C that has made a call Notification sound generator 5 for generating notification sounds such as ringback tones and operation sounds transmitted via L1, microphone amplifier 6 for amplifying a call signal (sending signal) output from microphone 1, and microphone amplifier The first A / D converter 7a that converts the analog transmission signal amplified in step 6 into a digital signal, and the first D / A that converts the digital call signal (received signal) output from the call processing unit 4 into an analog signal Co A first codec unit 7 having a barter 7b, a buffer amplifier 8 connected to the output side of the first D / A converter 7b, and a digital transmission signal output from the call processing unit 4 are converted into analog signals. The 2D / A converter 9a, the second codec unit 9 having the second A / D converter 9b for converting the analog call signal (received signal) transmitted from the child unit C into a digital signal, and the notification sound generation unit 5 From the third D / A converter 10 and the fourth D / A converter 11 for converting the generated digital notification sound into an analog signal, the buffer amplifier 12 connected to the output side of the third D / A converter 10, and the buffer amplifier 12 Attenuator 13 that adjusts the volume of the notification sound by attenuating the output analog signal (notification sound signal), and attenuated by attenuator 13 A first analog signal superimposing unit 14 that superimposes the notification sound signal on the reception signal output from the buffer amplifier 8; a speaker amplifier 15 that amplifies the output signal of the first analog signal superimposing unit 14 and outputs the amplified signal to the speaker 2; A buffer amplifier 16 connected to the output side of the 4D / A converter 11, a buffer amplifier 17 connected to the output side of the second D / A converter 9a, and an analog signal (notification sound signal) output from the buffer amplifier 16 A second analog signal superimposing unit 18 that superimposes the transmission signal output from the buffer amplifier 17, a buffer amplifier 19 connected to the input side of the second A / D converter 9b, and a control unit 20 that controls the entire master unit. With. The call processing unit 4 and the notification sound generating unit 5 are configured by a DSP (digital signal processor) loaded with a dedicated program (software), and the control unit 20 is configured by a CPU loaded with control software. .

  Although not shown, the call processing unit 4 includes a voice switch and first and second echo cancellers in order to realize a two-way voice call. The voice switch is well known in the art, and switches the call mode (transmission mode and reception mode) by comparing the levels of the transmission signal and the reception signal and inserting a loss in the signal path having the lower level. . The first and second echo cancellers have a conventionally known configuration including an adaptive filter and a subtracter, and adapt the impulse response of the feedback path (acoustic echo path) formed by acoustic coupling between the speaker 2 and the microphone 1. By subtracting an echo component (acoustic echo) adaptively identified by a filter and estimated from a reference signal (output signal to the first D / A converter 7b) from an input signal from the first A / D converter 7a by a subtractor. This cancels out the echo component. Further, the second echo canceller also has a conventionally known configuration including an adaptive filter and a subtracter. The reflection due to impedance mismatch between the 2-wire-to-wire converter 3 and the signal line L1 and the speaker in the child unit C The impulse response of the feedback path (line echo path) formed by the acoustic coupling between the microphones is adaptively identified by the adaptive filter, and the reference signal (the output signal to the second D / A converter 9a, that is, the transmission signal) The echo component (line echo) estimated from the above is subtracted from the received signal by a subtractor to cancel and cancel the echo component.

  On the other hand, the notification sound generation unit 5 generates a digital ringing tone by appropriately selecting from a plurality of ringing sounds prepared in advance, or selects a digital sound by appropriately selecting from a plurality of warning sounds similarly prepared in advance. Can generate a digital voice message by appropriately selecting and reading and decompressing a plurality of voice message data stored in a built-in or external memory and compressing it in the memory. A plurality of stored melody sound data is appropriately selected, read, and expanded to generate a digital melody sound. Here, the alarm sound is for notifying the resident of the occurrence of an abnormality such as a fire or gas leak, the voice message is a message (alarm message) for notifying the abnormality, and the melody sound is a ringing sound. It is used as

  The notification sound generation unit 5 also has a function of generating a specific sound as an excuse for letting the other party call and stop the call. For example, when a family member responds to a call from the child device C, the other party (calling party) is an uninvited visitor such as a salesman. And the housekeeper may want. In such a case, you can create an excuse to stop the call by letting the other party hear a sound such as a telephone ringing tone or a child's cry (named "specific sound"). For example, "The phone is ringing now "Please pick up." Or "Please pick up because the child is crying and you can't take your hands off."

Thus, a notification sound signal such as a ringing tone, a warning sound, or a voice message generated by the notification sound generation unit 5 is output from the call processing unit 4 by the first or second analog signal superimposing units 14 and 18. It is superimposed on the call signal (transmitted signal and received signal) and output to the speaker 2 or the 2-wire-4 wire conversion unit 3, and the received voice and the notification sound are individually or overlapped from the speaker of the master unit or the slave unit C, respectively. You will hear it. When the notification sound is output from the speaker 2 of the main unit superimposed on the received voice, the volume of the notification sound is adjusted by changing the attenuation amount of the attenuator 13 so that the notification sound does not interfere with the call. .
JP 2002-368891 A

  By the way, in the above conventional example, the third and fourth D / A converters 10 are used to convert the digital notification sound into an analog signal separately from the first and second codec units 7 and 9 that perform analog-digital conversion of the call signal. , 11, the number of parts increases, which hinders downsizing and cost reduction.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an interphone device that can be reduced in size and cost by reducing the number of components.

  In order to achieve the above object, the invention of claim 1 comprises an interphone device that is provided in a house with a microphone and a speaker, and an interphone handset that is provided outside the house with a microphone and a speaker. A communication path forming means for forming a communication path between the interphone device and the interphone handset through an appropriate communication path formed between the interphone device and the interphone handset, and a call signal transmitted / received through the communication path. A communication processing means for performing two-way loudspeaking by digital signal processing, and a notification for generating various notification sounds as digital notification sound data, such as a ringing tone for notifying a call from an intercom handset Sound generation means, volume adjustment means for adjusting the volume of notification sound data generated by the notification sound generation means, and volume adjustment Superimposing means for superimposing the notification sound data adjusted in the stage on the digital call signal output from the call processing means, and the analog-digital for converting the digital call signal and notification sound data superimposed by the superimposing means into an analog signal Conversion means.

  According to the present invention, since the alarm sound data is converted into an analog signal after being superimposed on the digital call signal, a digital-analog conversion circuit dedicated to the alarm sound data becomes unnecessary, and the number of parts can be reduced as compared with the conventional example. Downsizing and cost reduction.

  According to a second aspect of the present invention, in the first aspect of the present invention, the loss insertion means inserts a loss into the speech path from the analog-digital conversion means to the speaker, and the loss insertion means according to the type of signal passing through the speech path. Loss adjusting means for adjusting the amount of insertion loss is provided.

  According to the present invention, the volume of the call voice output from the speaker is adjusted after the conversion to the analog signal. Therefore, the call signal is compared with the case where the volume of the call voice is adjusted by digital signal processing in the call processing means. Can improve the call quality.

  A third aspect of the invention is characterized in that, in the second aspect of the invention, the volume adjusting means adjusts the volume of the notification sound data in accordance with the amount of insertion loss adjusted by the loss adjusting means.

  According to the present invention, the attenuation of the notification sound due to the volume adjustment of the call voice can be compensated for by the tone adjustment means, and the volume of the notification sound can be adjusted independently of the volume of the call voice.

  According to the present invention, since the alarm sound data is converted into an analog signal after being superimposed on the digital call signal, a digital-analog conversion circuit dedicated to the alarm sound data is not required, and the number of parts can be reduced as compared with the conventional example. This has the effect of reducing the size and cost.

  As shown in FIG. 2, the interphone device according to the present embodiment includes an interphone master unit (hereinafter referred to as “master unit”) that forms an interphone system together with one to a plurality of interphone slave units (hereinafter referred to as “slave units”) C. ) A and one or a plurality of interphone sub-master devices (hereinafter referred to as “sub-master devices”) B, and the slave device C and the sub-master device B and the master device A are connected by two signal lines L1 and L2, respectively. Is done. However, since the basic configuration of the base unit A of this embodiment is almost the same as that of the conventional example shown in FIG. 6, the same components are denoted by the same reference numerals and the description thereof is omitted.

  The child device C includes a microphone, a speaker, a two-wire / four-wire conversion circuit, and the like, and is installed at a front door outside the house. When a visitor presses the call button of the child device C, a call signal is transmitted to the parent device A through the signal line L1.

  Base unit A alternatively forms a communication path via signal lines L1 and L2 between microphone 1 and speaker 2, 2-wire to 4-wire conversion unit 3, and handset C or sub-base unit B. Amplifying by a speech path forming unit 21, a speech processing unit 4 that performs a two-way loudspeaking process by digitally processing a speech signal transmitted / received through the speech path, a DSP 22 that constitutes a notification sound generating unit 5, and a microphone amplifier 6 A first A / D converter 7a for converting the analog analog transmission signal into a digital signal, and a first D / A converter 7b for converting the digital reception signal output from the call processing unit 4 into an analog signal. The codec unit 7, the second D / A converter 9 a that converts the digital transmission signal output from the call processing unit 4 into an analog signal, and the analog receiver transmitted from the slave unit C or the sub master unit B Control for transmitting / receiving a control signal through the signal line L2 between the second codec unit 9 having the second A / D converter 9b for converting the signal into a digital signal and the sub master unit B under the control of the control unit 20. A signal transmission / reception unit 23 and an operation unit 24 including a plurality of switches SW1 to SW4 that output trigger signals for starting various processes to the control unit 20 are provided. Note that the call processing unit 4 includes a voice switch and first and second echo cancellers realized by executing dedicated software on the DSP 22 as in the conventional example.

  FIG. 1 is a block diagram excerpted from the configuration of the main unit A related to the gist of the present invention, that is, the configuration in which the notification sound is superimposed on the received voice and output from the speaker 2. The DSP 22 is generated by the sound control unit 22 a that realizes functions such as data transmission with the control unit 20 and software control for selecting and executing a plurality of software stored in the program memory, and the notification sound generation unit 5. A variable gain amplifier 22b that amplifies the notification sound data, a volume adjustment unit 22c that adjusts the volume of the notification sound by adjusting the gain of the variable gain amplifier 22b, and the volume-adjusted notification sound data from the call processing unit 4. And a superimposing unit 22d for adding and superimposing the digital reception signal to be output. However, the voice control unit 22a, the variable gain amplifier 22b, the volume adjustment unit 22c, and the superimposition unit 22d are realized by executing dedicated software on the DSP 22 in the same manner as the call processing unit 4 and the notification sound generation unit 5. . In addition, a buffer amplifier 25 and an attenuator 26 as loss insertion means are inserted in the speech path between the first codec section 7 and the speaker amplifier 15. The attenuator 26 is controlled by the control unit 20 to insert loss into the speech path, and the control unit 20 serves as loss adjustment means for adjusting the amount of insertion loss by the attenuator 26.

  The secondary master unit B has almost the same configuration as that of the master unit A except that the slave unit C is not directly connected. The description is omitted.

  Next, the operation of base unit A in the present embodiment will be described with reference to the drawings.

  First, an operation when a call is made between the slave unit C or the sub master unit B will be described with reference to FIG. FIG. 3 shows the occurrence of an event in the parent device A and the contents of the processing accompanying it.

  When the call button of the operation unit 24 is pressed in response to a call from the slave unit C or the sub master unit B, a call start trigger signal is input to the control unit 20 from the switch SW1. Then, the control unit 20 outputs a control signal to reduce the insertion loss amount (attenuation amount) of the attenuator 26 from 1 to 1 / N (N is 2 for example), and then starts a call to the voice control unit 22a of the DSP 22 Send the control command. Upon receiving this control command, the voice control unit 22a activates the call processing unit 4 to permit the output of call signal (received signal) data. At this time, if the notification sound data to be superimposed on the reception signal data is not generated, only the reception signal data R output from the call processing unit 4 is output from the superimposition unit 22d to the first codec unit 7 to be analog. Converted to signal R ′. Further, the analog signal R ′ is attenuated to 1 / N by the attenuator 26 and then output to the speaker 2 through the speaker amplifier 15, and the received voice R ″ (= R ′ / N = R) whose volume is adjusted from the speaker 2. When the call button is pressed again during a call and a call end trigger signal is input from the switch SW1 to the control unit 20, the control unit 20 calls the voice control unit 22a of the DSP 22. After transmitting the end control command, a control signal is output to return the attenuation amount of the attenuator 26 from 1 / N to 1 × In the voice control unit 22a receiving the call end control command, the call processing unit 4 When the notification sound data is not generated at this time, the output of the speaker 2 is silent.

  Next, the operation when only the notification sound is output from the speaker 2 will be described with reference to FIG. Note that FIG. 4 also shows the occurrence of an event in the parent device A and the contents of the process accompanying it as in FIG.

  For example, when the indoor call button of the operation unit 24 is pressed to call any of the sub-master devices B installed in the house, a trigger signal for starting the indoor call is input to the control unit 20 from the switch SW3. . Then, the control unit 20 outputs a control signal to set the attenuation amount of the attenuator 26 to 1 time, and then notifies the voice control unit 22a of the DSP 22 of the notification sound (the ringback output from the speaker 2 during the call of the sub master unit B). Tone) type and volume, and a control command for instructing output start is transmitted. Upon receiving this control command, the voice control unit 22a gives a command to the volume adjustment unit 22c to set the volume (for example, three levels of large, medium, and small) designated by the control command to the volume adjustment unit 22c. In accordance with this command, the volume adjusting unit 22c sets the gain of the variable gain amplifier 22b to the maximum value G3 (= 1 times). Subsequently, the voice control unit 22a gives a command for causing the notification sound generation unit 5 to generate the type of notification sound instructed by the control command, and the notification sound data T generated by the notification sound generation unit 5 in accordance with this command is the variable gain amplifier. Amplified by 22b and output to the superimposing unit 22d. At this time, since there is no reception signal data to be superimposed on the notification sound data T, only the notification sound data T output from the notification sound generation unit 5 is output from the superimposition unit 22d to the first codec unit 7 to be an analog signal. Converted to T ′. Further, the analog signal T ′ passes through the attenuator 26 and is output to the speaker 2 through the speaker amplifier 15, and the notification sound T ″ (= T ′ = T) whose volume is adjusted is sounded from the speaker 2.

  When the volume setting button is pressed during a room call and a volume change trigger signal is input to the control unit 20 from the switch SW4, the control unit 20 transmits a volume change control command to the voice control unit 22a of the DSP 22. . In the voice control unit 22a that has received the control command for changing the volume, the volume adjustment unit issues a command to set the volume (for example, three levels of large, medium, and small) instructed by the control command to the volume adjustment unit 22c. 22c, and in accordance with this command, the volume adjusting unit 22c sets the gain of the variable gain amplifier 22b to the minimum value G1 (= 0.1 times). As a result, the volume of the notification sound data T input to the superimposing unit 22d is reduced by a factor of 0.1. In this case, the notification sound T ″ (= T ′ = 0.1 × T) with the minimum volume is set. Sounded from the speaker 2. Further, when the stop button is pressed during the room call and the trigger signal for the end of the room call is input from the switch SW2 to the control unit 20, the control unit 20 notifies the voice control unit 22a of the DSP 22. The sound control unit 22a that has received the control command for stopping the notification sound sets the volume control unit 22c to the standby state, and then instructs the notification sound generation unit 5 to stop generating the notification sound. Therefore, the output of the speaker 2 becomes silent.

  Finally, the operation when the notification sound is superimposed on the call voice and output from the speaker 2 as in the case where a call is made from the handset C during a call with the sub-master B will be described with reference to FIG. . Note that FIG. 5 also shows the occurrence of an event in the parent device A and the contents of the process accompanying it as in FIGS. 3 and 4.

  When a call with the secondary master unit B is started in the procedure already described and a call signal from the slave unit C is detected during the call, the control unit 20 informs the voice control unit 22a of the DSP 22 of a notification sound (slave unit C). The control command for instructing the start and output of the type and volume of the ringing tone for calling from the device). Upon receiving this control command, the voice control unit 22a gives a command to the volume adjustment unit 22c to set the volume (for example, three levels of large, medium, and small) designated by the control command to the volume adjustment unit 22c. give. In response to this command, the volume adjusting unit 22c sets the gain of the variable gain amplifier 22b to the maximum value G3 (= 1 ×) × N times in order to maximize the volume of the notification sound output from the speaker 2. That is, since the notification sound signal superimposed on the call signal is attenuated by 1 / N by the attenuator 26, the attenuation by the attenuator 26 is compensated by previously multiplying the notification sound data by the variable gain amplifier 22b. It is what.

  Subsequently, the voice control unit 22a gives a command for causing the notification sound generation unit 5 to generate a notification sound of the type specified by the control command, and the notification sound data T ′ (= T) generated by the notification sound generation unit 5 in accordance with this command. × N) is amplified by the variable gain amplifier 22b and output to the superimposing unit 22d. Then, the reception signal data R and the notification sound data T ′ output from the call processing unit 4 are superimposed by the superimposing unit 22 d and converted into an analog signal W (= R ′ + T ′) by the first codec unit 7. Further, the analog signal W is attenuated to 1 / N by the attenuator 26 and then output to the speaker 2 through the speaker amplifier 15, and the received voice R ″ (= R ′ / N = R / N) and a notification sound T ″ (= T ′ / N = T) are sounded.

  Note that the sub-master unit B performs the same operation as the above-described master unit A.

  Thus, in the interphone device (base unit A and sub-base unit B) of the present embodiment, the notification sound data is converted into an analog signal after being superimposed on the digital call signal (received signal) as described above. A D / A converter dedicated to notification sound data is not required, and the number of parts can be reduced as compared with the conventional example, so that the size and cost can be reduced. Further, since the volume of the call voice output from the speaker 2 is adjusted by the attenuator 26 after conversion to an analog signal, the call is compared with the case where the volume of the call voice is adjusted by digital signal processing in the call processing unit 4. The dynamic range of the signal can be increased to improve the call quality, and the attenuation of the notification sound due to the volume adjustment of the call voice can be compensated for by the tone adjustment unit 22c. It can be adjusted independently of the volume.

It is a block diagram which shows the principal part of the intercom main unit which is embodiment of this invention. It is a block diagram of an intercom system including the interphone master device and the interphone sub-master device. It is operation | movement explanatory drawing in the case of performing a telephone call between an interphone subunit | mobile_unit or an interphone sub-master | base_unit in the same as the above. It is operation | movement explanatory drawing in the case of ringing only a notification sound in the same as the above. It is operation | movement explanatory drawing in the case of ringing a call voice and a notification sound in the same as the above. It is a block diagram which shows a prior art example.

Explanation of symbols

2 Speaker 4 Call processing unit 5 Notification sound generation unit 7 First codec unit 20 Control unit 22 DSP
22a Audio control unit 22b Variable gain amplifier 22c Volume adjustment unit 22d Superimposition unit 26 Attenuator

Claims (3)

  A telephone call formed between an interphone device and an interphone slave unit, which is composed of an interphone device that is installed in a house with a microphone and a speaker, and an interphone slave unit that is installed outside the house with a microphone and a speaker. Used in an intercom system for making calls over a road, a call path forming means for forming a call path with an interphone handset, and a call process for performing a two-way voice call by digitally processing a call signal transmitted / received through the call path A notification sound generating means for generating, as digital notification sound data, a notification sound for transmitting various information such as a ringing tone for notifying a call from the interphone handset, and a notification sound generated by the notification sound generation means Volume adjustment means for adjusting the volume of the data, and the notification sound data adjusted by the volume adjustment means as call processing means An intercom device comprising superimposing means for superimposing an output digital call signal, and an analog-digital conversion means for converting the digital call signal and notification sound data superimposed by the superimposing means into an analog signal .   Loss insertion means for inserting loss into the speech path from the analog-digital conversion means to the speaker, and loss adjustment means for adjusting the amount of insertion loss by the loss insertion means in accordance with the type of signal passing through the speech path The intercom device according to claim 1.   The interphone apparatus according to claim 2, wherein the volume adjusting means adjusts the volume of the notification sound data in accordance with the amount of insertion loss adjusted by the loss adjusting means.

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