JP4661586B2 - Audio transmission system - Google Patents

Description

  The present invention relates to an audio transmission system that transmits an audio signal via a signal line.

Conventionally, as an audio transmission system that transmits an audio signal via a signal line, for example, a lobby interphone installed at a common entrance of an apartment house and a dwelling unit installed in each dwelling unit via a signal line There is an intercom system that transmits and receives audio signals (see, for example, Patent Document 1). In such a conventional system, the lobby interphone and each dwelling unit are connected by two lines of a signal line for transmitting an audio signal and a signal line for call control.
JP 2005-260359 A

  However, in the above-described conventional example, a large number of terminal devices (lobby intercoms and dwelling units) must be connected by two systems of signal lines for audio signals and signal lines for control signals. There is a problem that labor is required and the cost increases.

  Further, in the above conventional example, when a lobby interphone and any one of the dwelling units are calling, another dwelling unit cannot make a call. In addition, as a system for making a call between a plurality of sets of call terminals simultaneously, a system using a technology (VoIP <Voice over Internet Protocol>) that transmits and receives voice data using a TCP / IP network such as the Internet or an intranet (LAN). However, there are cases where sufficient call quality cannot be obtained because packets other than voice data flow on the network.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an audio transmission system capable of simplifying the construction work of signal lines and enabling multi-channel audio while ensuring call quality. There is.

In order to achieve the above object, the invention of claim 1 provides one or more voice input terminal devices including voice input means for inputting at least voice and one or more voice output means for outputting voice at least. A voice input terminal device, a voice input terminal device, and a main device connected to the voice output terminal device via a signal line and performing call control between the voice input terminal device and the voice output terminal device. An audio transmission system for transmitting an audio signal via a signal line to an audio output terminal device, the audio input terminal device comprising: the audio input unit; an amplifying unit for amplifying the audio input from the audio input unit ; including encoding means, modulation means for modulating the encoded audio data, the audio data, wherein the modulated in the time slots allocated for encoding speech amplified by means A voice output terminal comprising: a transmission means for storing a voice signal and transmitting the signal via a signal line; and a control signal transmission / reception means for storing and transmitting the control signal in a time slot assigned for call control via the signal line. An apparatus includes: a receiving unit that receives an audio signal transmitted via a signal line; a demodulating unit that demodulates an audio signal received by the receiving unit; a decoding unit that decodes demodulated audio data; Amplifying means for amplifying the received voice ; the voice output means for outputting the voice amplified by the amplifying means; and a control signal for storing and transmitting a control signal in a time slot assigned for call control via a signal line And a transmission / reception means, wherein the main device transmits a synchronization signal for defining the time slot to each terminal device via a signal line, and is assigned for call control via the signal line. Control signal transmission / reception means for storing and transmitting a control signal in the assigned time slot, and a call to the requested voice output terminal device when a control signal for a call establishment request is received from any voice input terminal device It transmits a control signal for establishment request and a call control means for notifying the assignment of time slots for storing audio signals to the requesting audio input terminal and the request destination of the audio output terminals, audio The amplifying means of the input terminal device and the amplifying means of the audio output terminal device are activated after notification of time slot assignment from the main device, and the transmitting device of the audio input terminal device and the receiving device of the audio output terminal device are the main device. The voice signal is stored and transmitted / received in a time slot assigned from the above.

  The invention of claim 2 is characterized in that, in the invention of claim 1, the control signal transmitting / receiving means of the main apparatus transmits and receives the control signal by a polling method.

  The invention of claim 3 is characterized in that, in the invention of claim 1, the control signal transmission / reception means of the main apparatus transmits / receives a control signal by a carrier detection multiple access system.

  According to the present invention, since a control signal for call control is stored in a time slot in the same way as a voice signal and transmitted through a common signal line, the construction work of the signal line can be simplified, and the voice signal is time-division multiplexed. As a result, the voice quality can be increased and the number of voice channels can be increased.

  As shown in FIG. 1, the audio transmission system according to the present embodiment is connected to a plurality of terminal devices 2 that transmit and receive audio signals via a signal line Ls, and to the terminal devices 2 through signal lines Ls. And a main apparatus 1 for transmitting a synchronization signal SY for defining a time slot TSi (i = 1, 2,..., N) described later. Here, a balanced line such as a pair line is used as the signal line Ls, but an unbalanced line such as a coaxial line may be used. Further, a pair of enhanced category 5 or category 6 LAN cables or a pair of CPEV cables may be used for the signal line Ls.

  As shown in FIG. 1, the terminal device 2 includes a microphone 20a and a speaker 21a, a microphone amplifier 20b that amplifies the output of the microphone 20a, a speaker amplifier 21b that amplifies the input to the speaker 21a, and the output of the microphone amplifier 20b. An A / D converter 20c that converts the signal into a signal, a D / A converter 21c that converts the digital signal output from the encoding / decoding unit 22 into an analog signal and inputs the analog signal, and a digital signal An encoding / decoding unit 22 that encodes and decodes the generated audio, and generates audio signals by modulating the audio data encoded by the encoding / decoding unit 22 and is captured from the signal line Ls Modulator / demodulator 23 that demodulates audio data from the received audio signal, and a transmitter that amplifies the audio signal output from modem 23. Comprising a flop 24a, a receiving amplifier 24b for amplifying an audio signal input to the modem unit 23, a control unit 25 that controls each unit by the CPU as a main component. That is, since the terminal device 2 in the present embodiment includes both a voice input unit (microphone 20a) for inputting voice and a voice output unit (speaker 21a) for outputting voice, the terminal device 2 is a voice input terminal device. At the same time, it is a voice output terminal device. However, the configuration of the terminal device 2 is not limited to this, and a voice input terminal device having voice input means and no voice output means, or voice having voice output means and no voice input means. It may be configured as an output terminal device. Each terminal device 2 is given a unique identification code (ID), and each terminal device 2 can be identified by this identification code. Further, the modem unit 23 demodulates the control data from the control signal taken from the signal line Ls by processing to generate control signals by modulating control data (to be described later) given from the control unit 25, and the control unit 25. Processing to pass to.

  The main device 1 generates a synchronization signal SY and a control signal by modulating a control unit 10 having a CPU as a main component, and synchronization data and control data (described later) given from the control unit 10, and from a signal line Ls. A modulation / demodulation unit 11 for demodulating control data from the captured control signal.

  The synchronization signal SY is composed of a header part and a data part as shown in FIG. The header part includes a preamble, a packet type, a modulation method, a data length, and an error correction code. On the other hand, the data part is composed of synchronous data (actually empty) and an error correction code. As shown in FIG. 2B, the audio signal is also composed of a header part and a data part. The header part includes a preamble, an identification code (ID) indicating the terminal device 2 that is the transmission source, a packet type, a modulation method, a data length, and an error correction code. On the other hand, the data part is composed of audio data and error correction codes. The synchronization signal SY is modulated by a modulation method such as BPSK (Binary Phase Shift Keying) in both the header part and the data part, and the audio signal is BPSK in the header part, BPSK or QPSK (Quadrature Phase Shift Keying) in the data part, and 16QAM. (Quadrature Amplitude Modulation) and modulation by 64QAM or the like. Although not shown, the control signal is composed of a header part common to the audio signal and a data part composed of control data and an error correction code.

  In the main apparatus 1 and the terminal apparatus 2, as shown in FIG. 3, a period until a next synchronization signal SY rises with a time when a predetermined time has elapsed from the fall of the synchronization signal SY as a start time of the first time slot TS1. A plurality (n) of time slots TS1, TS2,..., TSn are arranged within (signal transmission period). Here, in the present embodiment, n time slots TSi are arranged in the signal transmission period. Among these, the first time slot TS1 is allocated to the downlink control signal from the main apparatus 1 to the terminal apparatus 2. Since the second time slot TS2 is assigned to the upstream control signal from the terminal device 2 to the main device 1, the maximum (n-2) / 2 terminal devices 2 transmit and receive audio signals on a one-to-one basis. it can.

  Next, the operation of the present embodiment when a one-to-one call (individual call) is performed between the two terminal devices 2 will be described with reference to FIG. In the following, a case where two devices, terminal device A and terminal device B, make an individual call will be exemplified.

  The control unit 10 of the main apparatus 1 sequentially polls each terminal apparatus 2 cyclically in the downlink time slot TS1. Then, when a call button (not shown) is operated in the terminal device A, the control unit 25 generates a call (call establishment) request that is control data for calling the partner terminal device B. And the other party's identification code are supplied to the modem 23, and the control signal modulated by the modem 23 is stored in the upstream time slot TS2 following the time slot TS1 polled by itself, and transmitted to the signal line Ls. Let

  On the other hand, the main apparatus 1 receives the control signal stored and transmitted in the time slot TS2 in the uplink direction, demodulates it by the modem unit 11, and receives control data (call request), caller ( The control unit 10 receives the identification code of the request source and the identification code of the callee (request destination). The control unit 10 stores the control signal including the call request with the call destination identification code as the destination in the next downlink time slot TS1 and causes the modem unit 11 to transmit the control signal.

  When the modulation / demodulation unit 23 of the called terminal device B demodulates the control signal transmitted from the main device 1, and passes the call request included in the demodulated control signal to the control unit 25, the control unit 25 notifies the notification sound from the speaker 21a. Make a ringing tone. When a response button (not shown) is operated in the terminal device B, the control unit 25 generates an affirmative response indicating that the individual call with the calling terminal device A is accepted, and the modem unit 23 A control signal including an acknowledgment and its own identification code is modulated, stored in the upstream time slot TS2 via the demultiplexing unit 27, and returned to the main apparatus 1.

  In the main device 1, the control signal transmitted in the uplink time slot TS2 is demodulated by the modulation / demodulation unit 11, and the acknowledgment and the call destination (request destination) identification code included in the demodulated control signal are sent to the control unit 10. Then, the control unit 10 modulates the control signal including the call establishment notification with the caller identification code as the destination, and stores and modulates the control signal in the next downlink time slot TS1. Further, in the next downlink time slot TS1, the control unit 10 controls the call source and the call destination terminal devices A and B to notify the allocation of the time slots TS3 and TS4 each storing a voice signal. The signal is transmitted from the control signal transmission / reception unit 11.

  In the call source terminal device A and the call destination terminal device B, the control unit 25 includes a microphone amplifier 20b, a speaker amplifier 21b, an A / D converter 20c, a D / A converter 21c, and an encoding / decoding unit 22. The modulation / demodulation unit 23, the transmission amplifier 24a, and the reception amplifier 24b are activated, and the audio signal collected by the microphone 20a, encoded by the encoding / decoding unit 22 and modulated by the modulation / demodulation unit 23 is transmitted from the main apparatus 1 to itself. The data is stored in the assigned time slot TS3 or TS4 and transmitted via the signal line Ls, and the voice signal stored in the time slot TS4 or TS3 assigned to the other party is taken in and demodulated by the modem 23 and the voice data Is decoded by the encoding / decoding unit 22, and the other party's voice is sounded from the speaker 21a. In this way, the two terminal apparatuses A and B transmit and receive audio signals using the mutually different time slots TS3 and TS4, thereby enabling individual calls.

  Next, the operation of the present embodiment when a many-to-many call (simultaneous call) is performed between the three terminal devices 2 will be described with reference to FIG. In the following, a case where three devices, terminal device A, terminal device B, and terminal device C, make a simultaneous call will be exemplified.

  First, when a general call button (not shown) is operated in the terminal device A, the control unit 25 generates a general call request for calling other terminal devices B and C all at once, and identifies the general call request and the self. The code and the identification code of the other party are given to the modem unit 23, the control signal modulated by the modem unit 23 is stored in the upstream time slot TS2 following the time slot TS1 polled by itself, and transmitted to the signal line Ls.

  On the other hand, main apparatus 1 receives a control signal stored and transmitted in uplink time slot TS2, demodulates it by modem 11, and sends a general call request and caller identification code included in the demodulated control signal. It passes to the control unit 10. The control unit 10 stores a control signal including a general call request in the next downlink time slot TS1 with the identification code of the general call destination as a destination, and transmits the control signal from the modem unit 11.

  When the modulation / demodulation unit 23 of the terminal devices B and C of the general call destination demodulates the control signal transmitted from the main device 1 and passes the general call request included in the demodulated control signal to the control unit 25, the control unit 25 A notification sound (ringing sound) is generated from 21a. Then, when a response button (not shown) is operated in the terminal devices B and C, the control unit 25 generates an acknowledgment to the effect that the simultaneous communication is accepted, and the modem unit 23 receives the acknowledgment and the own response. The control signal including the identification code is modulated, stored in the upstream time slot TS2 via the demultiplexing unit 27, and returned to the main apparatus 1.

  In the main apparatus 1, the control signal transmitted in the uplink time slot TS2 is demodulated by the modulation / demodulation unit 11, and the acknowledgment and the identification code of the general call destination included in the demodulated control signal are passed to the control unit 10 for control. The unit 10 modulates the control signal including the call establishment notification with the caller identification code as the destination, and stores and modulates the control signal in the next downlink time slot TS1. Further, in the next downlink time slot TS1, the control unit 10 notifies the call source and call destination terminal devices A, B, and C of the assignment of the time slot TSi in which each stores a voice signal. Is modulated by the modem 11 and transmitted.

  Here, in the case of a simultaneous call, a time slot TS3, TS4, TS5 for transmission (transmission) and a time slot TS6, TS7, TS8 for reception (reception) are assigned to each terminal device A, B, C. It is done.

  In each of the terminal devices A, B, and C, the control unit 25 includes a microphone amplifier 20b, a speaker amplifier 21b, an A / D converter 20c, a D / A converter 21c, an encoding / decoding unit 22, a modem unit 23, The transmission amplifier 24a and the reception amplifier 24b are activated, and the audio signal collected by the microphone 20a, encoded by the encoding / decoding unit 22 and modulated by the modulation / demodulation unit 23 is transmitted from the main apparatus 1 to itself. And stored in the time slots TS3, TS4, TS5 for transmission via the signal line Ls. Here, in the main device 1, the audio signal stored in the transmission time slots TS3, TS4, TS5 is taken into the control unit 10, and the audio data obtained by combining the audio data transmitted from the terminal devices B and C by the control unit 10 is used. A signal is generated and stored in the reception time slot TS6 assigned to the terminal device A, and a voice signal obtained by combining the voice data transmitted from the terminal devices A and C is generated and assigned to the terminal device B. And a voice signal obtained by combining the voice data transmitted from the terminal devices A and B is generated and stored in the reception time slot TS8 assigned to the terminal device C.

  Therefore, the terminal devices A, B, and C take in the audio signals stored in the reception time slots TS6, TS7, and TS8, demodulate them by the modem unit 23, and decode the audio data by the encoding / decoding unit 22. The terminal device A can hear the sound transmitted from the other terminal devices B and C, and the terminal device B can hear the sound transmitted from the other terminal devices A and C. In C, since voices transmitted from other terminal apparatuses A and B can be heard, simultaneous communication is possible.

  As described above, according to the present embodiment, it is possible to increase the number of voice channels while ensuring call quality by time-division-multiplexing and transmitting a voice signal, and the control signal for call control can be used as a voice signal. Similarly to the above, since the data is stored in the time slot TSi and transmitted through the common signal line Ls, there is an advantage that the construction work of the signal line Ls can be simplified.

  In this embodiment, the assignment of the time slot TSi to the terminal device 2 is notified by the control signal. However, the assignment of the time slot TSi to the terminal device 2 can be notified by the synchronization signal SY instead of the control signal. It is. For example, it is only necessary to transmit data associating the identification code of each terminal device 2 with the allocation of the time slot TSi as the synchronization data constituting the data portion of the synchronization signal SY. If the synchronization signal SY is used to notify the assignment of the time slot TSi in this way, the procedure for transmitting the control signal to notify the assignment of the time slot TSi becomes unnecessary.

  In this embodiment, the polling method is adopted for transmission (transmission / reception) of the control signal between the main device 1 and the terminal device 2, but a CSMA (carrier detection multiple access) method may be adopted. However, in the polling method, it is necessary to always transmit the synchronization signal SY from the main device 1, but in the case of adopting the CSMA method, the synchronization signal SY is transmitted from the main device 1 after the call control is completed and the call is established. Just start.

  Here, as shown in FIG. 6, by simply connecting the connector of the functional module 108 to the connection port of the gate device 103, the power path and the information path of the functional module 108 can be secured at the same time. There is a wiring system that can be connected also to the gate device 103 and is excellent in workability. In this wiring system, one or a plurality of switch boxes 102 embedded and disposed at appropriate positions in a building are provided, and a power line 110 and an information line 111 that are wired in advance in a wall surface between the switch boxes 102 are sent and wired. At the same time, with respect to the switch box 102 at the starting end, a field line 110 drawn indoors through the main breaker MB and the branch breaker BB drawn into the wiring board 101, and a gateway 120 ( Information line 111 connected via a router and a hub is connected. It is also possible to incorporate the audio transmission system according to the present invention into such a wiring system.

It is a system configuration figure showing an embodiment of the present invention. (A) is explanatory drawing of the synchronizing signal same as the above, (b) is explanatory drawing of the audio | voice signal same as the above. It is a time chart of a synchronous signal and a time slot in the same as the above. It is operation | movement explanatory drawing at the time of the individual call in the same as the above. It is operation | movement explanatory drawing at the time of the simultaneous call in the same as the above. It is a system configuration diagram of a wiring system incorporating the same.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main apparatus 2 Terminal apparatus 10 Control part 11 Modulation / demodulation part 20a Microphone 21a Speaker 22 Encoding / decoding part 23 Modulation / demodulation part 25 Control part 27 Demultiplexing part SY Synchronous signal Ls Signal line

Claims (3)

One or more voice input terminal devices provided with at least voice input means for inputting voice, one or more voice output terminal devices provided with voice output means for outputting at least voice, voice input terminal devices, and voice output terminals A main apparatus that is connected to the apparatus via a signal line and performs call control between the voice input terminal apparatus and the voice output terminal apparatus, and transmits a voice signal from the voice input terminal apparatus to the voice output terminal apparatus via the signal line An audio transmission system,
The voice input terminal device includes the voice input unit, an amplifying unit for amplifying the voice input from the voice input unit, an encoding unit for encoding the voice amplified by the amplifying unit, and the encoded voice data. Modulating means for modulating, transmitting means for storing a voice signal including the modulated voice data in the assigned time slot and transmitting it through the signal line, and a time slot assigned for call control via the signal line Control signal transmitting and receiving means for storing and transmitting and receiving the control signal,
An audio output terminal device includes: a receiving unit that receives an audio signal transmitted via a signal line; a demodulating unit that demodulates an audio signal received by the receiving unit; and a decoding unit that decodes demodulated audio data; Amplifying means for amplifying the decoded sound ; sound output means for outputting the sound amplified by the amplifying means; and storing and transmitting a control signal in a time slot assigned for call control via a signal line Control signal transmitting and receiving means
The main device transmits a synchronization signal for defining the time slot to each terminal device via a signal line, and sends a control signal to the time slot allocated for call control via the signal line. Control signal transmission / reception means for storing and transmitting / receiving, and when receiving a call establishment request control signal from any of the voice input terminal devices, transmitting a call establishment request control signal to the requested voice output terminal device Call control means for notifying a request source voice input terminal device and a request destination voice output terminal device of allocation of time slots for storing voice signals;
The amplifying means of the voice input terminal device and the amplifying means of the voice output terminal device are activated after the main device is notified of the time slot assignment,
The voice transmission system, wherein the transmission means of the voice input terminal apparatus and the reception means of the voice output terminal apparatus store and transmit voice signals in a time slot assigned by the main apparatus.   2. The voice transmission system according to claim 1, wherein the control signal transmission / reception means of the main unit transmits / receives the control signal by a polling method.   2. The voice transmission system according to claim 1, wherein the control signal transmission / reception means of the main apparatus transmits / receives the control signal by a carrier detection multiple access method.

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