JPS63298598A - Radio type communication equipment - Google Patents

Abstract

PURPOSE:To execute the transmission of voice information at a low cost by adding a voice modulating circuit and a voice demodulating circuit, to a transmitter and a receiver of a conventional radio type communication equipment, respectively. CONSTITUTION:The titled equipment is provided with a PWM modulating circuit 6 for receiving a clock pulse from a crystal oscillating circuit 2 being a source oscillator through a frequency dividing circuit 5, and outputting a voice subcarrier wave of a square wave whose pulse width is determined by a current amplifying circuit 4 serving as a constant-current source and an external capacitor (c). Also, this equipment is provided with a PWM demodulating circuit 28 in which a regenerated pulse data signal from a waveform shaping circuit 26 is applied to a pulse data demodulating circuit 27 as usual and compared with pulse data stored in advance, and when they have coincided, an output signal is outputted to an output terminal, and also, a voice subcarrier wave signal shaped to a square wave by the waveform shaping circuit 26 is received and restored to a sound signal, an amplifier 30 for amplifying this sound signal, and a loudspeaker 32 for outputting said signal as a voice. In such a way, the transmission of voice information can be executed at a low cost.

Description

[Detailed description of the invention] ! Technical field of invention] The present invention relates to a wireless notification device capable of voice transmission.

1 Technical Background of the Invention] FIG. 4 is a block diagram showing an example of the configuration of a transmitter of a conventional wireless notification device. In FIG. , this signal is input to the pulse data generation circuit 3, which generates the determined pulse code data upon receiving the transfer signal based on the clock signal of the crystal oscillation circuit 2 as the source oscillation circuit. Output. The output of the pulse data generation circuit 3 and the pulse output of the crystal oscillation circuit 2 are NANDed, and the output pulse data signal of the pulse data generation circuit 3 is 1) (when in the J state, the output signal of the crystal oscillation circuit 2 is N of the gate operation that transmits to the next stage switching circuit 11
An AND circuit 1o is inserted, and the output signal of this NAND circuit 10 turns on/off the oscillation operation of the LC oscillation circuit 12 at the next stage.
A switching circuit 11 for controlling off is provided. The LC oscillation circuit g12, which oscillates at a frequency near the transmission frequency, has its oscillation turned on and off by the switching circuit 11, and as a result, the oscillation output is n times higher than the oscillation frequency of the source oscillation circuit to the next stage amplifier circuit 7. This amplified signal is radiated into the air via the antenna circuit 8. Note that 9 is a battery that energizes the circuit elements.

FIG. 5 is a schematic block diagram of a conventional receiver corresponding to the transmitter of the reporting device shown in FIG.

In the figure, reference numeral 2o denotes a receiving antenna that receives radio waves carrying transfer information from the transmitting antenna 8 and supplies them to a high frequency amplification circuit 21, and the amplified signal is sent to a local oscillation circuit 23 and a frequency mixing circuit. 22 into an intermediate frequency signal, this signal is amplified by an intermediate frequency amplification circuit 24, and then subjected to AM detection through an AM detection circuit 25. The configuration and operation up to this point are the same as a general receiver. after that.

This AM detection signal is shaped into a square wave by the waveform shaping circuit 26 and sent to the pulse data demodulation circuit 27. This pulse data demodulation circuit 27 is configured to compare the input pulse data signal with predetermined pulse data and send an output signal to the output terminal 31 when they match.

22, the operation of the transmitter of the wireless notification device configured as described above will be explained below with reference to the operation timing diagram of FIG.

As shown in the figure, when there is no notification signal input to the input terminal 1 (for example, the input is in the "L" state), the pulse data generation circuit 3
The output of the NAND circuit 1o is in the “L” state, and the output of the NAND circuit 1o is rH.
Since it is in the J state, the switching transistor Q of the switching circuit 11 is in the on state, and the L
Since the emitter potential of the oscillation transistor Q of the C oscillation circuit 12 has increased and it is in a reverse bias state,
Oscillation has stopped.

Next, when there is a notification signal input to the input terminal 1 (for example, input "HJ state"), from the output of the pulse data generation circuit 3,
When the determined pulse data is output (b in the figure) and the output is in the rHJ state, the oscillation output signal of the crystal oscillation circuit 2 as the source oscillator passes through the NANo circuit 10 (a in the figure),
It is output in reversed form (C in the figure). That is, when the output of the pulse data generation circuit 3 (b in the figure) and the output of the crystal oscillation circuit 2 (a in the figure) are both in the "H" state, the NAND circuit 1
The output of 0 is in the "L" state (c in the figure), and at this time, the switching transistor Q5 of the switching circuit 11 is turned off, and the oscillation transistor Q of the LC oscillation circuit 12 is normally biased and enters the oscillation state ( Figure d).

In the circuit configured as above, the LC oscillation circuit 1
The oscillation frequency f0 of 2 is the oscillation frequency fX of the crystal oscillation circuit 2.
It oscillates at n times T (n=2.3.4...). That is, fo=n-f)(T (=L*) However, f is the oscillation frequency of the LC oscillation circuit 12, fxT is the oscillation frequency of the crystal oscillation circuit 2, and f0 tree is the LC oscillation circuit 1.
The oscillation frequency of 2 alone is n=2.3.4... However, since the conventional wireless reporting device is configured as described above, it has a drawback that it cannot transmit audio information.

Furthermore, even if it were possible to send audio information, the audio signal would need to be converted into pulse code (PCM), making the device extremely expensive.

[Object of the Invention] In view of the above circumstances, the present invention provides an audio modulation circuit that modulates an audio subcarrier into a transmitter with audio without impairing compatibility with conventional wireless notification devices, and a corresponding audio modulation circuit. The purpose of this invention is to provide low-cost transmission of audio information by adding an audio demodulation circuit that demodulates the audio subcarrier to a receiver.

[Summary of the Invention] In order to achieve the above object, the present invention provides a wireless notification device that transmits a security signal based on a sensor output to the notification device main body side using a wireless transmitter at an appropriate transmission frequency, which includes a source oscillation circuit; When there is an oscillation circuit that oscillates at a frequency close to the transmission frequency and the security signal, there is a gate means for transmitting the output of the source oscillation circuit to the subsequent stage, and an output signal of the gate means turns on/off the oscillation circuit at the next stage.
A switching means for controlling the OFF operation is provided, thereby increasing the oscillation frequency by n times (n=2.3.4·
), an audio modulation circuit is added to the transmitter that provides the transmission frequency, and an audio demodulation circuit is added to the receiver.

[Embodiments of the invention] Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 are block diagrams of an embodiment of a transmitter and a receiver of a wireless notification device according to the present invention. In Figures 1 and 2, Figures 4 and 5
Elements that are the same as those in the figures are given the same reference numerals.

The difference between the transmitter of the wireless notification device of this embodiment and the conventional device shown in FIG. A PWM modulation circuit 6 is provided which outputs a square wave audio subcarrier determined by a current amplification circuit 4 as a current source and an external capacitor C. In this case, the repetition period of the output audio subcarrier is determined by the frequency of the clock pulse from the crystal oscillation circuit 2 input from the human power f.

Further, the current value of the current amplifying circuit 4 changes depending on the audio signal inputted from the microphone M, and the pulse width of the PWM modulating circuit 6 changes, thereby producing a PWM modulated wave. Furthermore, a switch S1 is provided between the pulse data generation circuit 3 and the NAND circuit 10, and the PWM modulation circuit 6 and the NAND circuit 10 are connected to each other.
A switch S2 is provided between the AND circuits 10 and configured to take timing.

Furthermore, the receiver of this embodiment differs from the conventional device shown in FIG. 5 in that the regenerated pulse data signal from the waveform shaping circuit 26 is applied to the pulse data demodulation circuit 27 and stored in advance as in the conventional case. compared with the pulse data
In addition to outputting an output signal to the output terminal when -M, a PWM demodulation circuit 28 receives the audio subcarrier signal shaped into a square wave by the waveform shaping circuit 26 and restores it to an audio signal. The point is that an amplifier 30 for amplifying the signal and a speaker 32 for outputting the signal as sound are provided.

This audio amplification circuit 30 is operated after the pulse data demodulation circuit 27 outputs the output signal to the output terminal.

When the input pulse data signal disappears, the squelch circuit 29 is operated and turned on for a certain period of time (the same time as the time when the audio signal is sent from the transmitter, or a slightly shorter time).

Next, the operation of the wireless notification device of this embodiment configured as described above will be explained below with reference to the timing chart shown in FIG.

As shown in FIG. 3, the output signal of the crystal oscillation circuit 2 (a in the diagram) is applied to one input α of the NAND circuit, and is also applied to the tarok signal of the pulse data generation circuit 3 and the frequency divider circuit 5. It is applied to the PWN modulation circuit 6 as a clock signal for subcarrier generation. When a transfer signal (IN in the figure) from a device such as a sensor connected to the input terminal 1 is input to the pulse data generation circuit 3, a certain predetermined pulse data signal is output from the output C (C in the figure). Output. While this pulse data signal is being output, the state of the output d changes (d in the figure), switch S1 is turned on, and the pulse data signal passes through this switch S1 and is added to the input of the NAND circuit 1o. (
(first half of figure b). Of the pulse data signals input to this human power source, only when the signal is in the rH state, the output signal of the crystal oscillation circuit 2 applied to the human power a is inverted and output (g in the figure). ). Thereafter, as in the conventional example, the above output signal is used to control the oscillation operation of the oscillation circuit 12 on and off via the switching transistor Q2, and is multiplied by n (n
= 2.3.4...) to obtain the transmission frequency (D in the figure)
). After the output of the pulse data signal from the output C of the pulse data generation circuit 3 is terminated, the output d returns to its original state and the switch S1 is turned off (d in the figure). At the same time, output e
The state of the switch S2 changes (e in the figure) and the switch S2 is turned on. On the other hand, the repetition period of the square wave audio subcarrier output from the PWM modulation circuit 6 is determined by the frequency of the clock signal input from the input f (f in the figure), and its pulse width is as described above. The current amplifier circuit 4 as a constant current source and the external capacitor C are determined. In addition, as mentioned above, the current value of the current amplifier circuit 4 changes depending on the input audio signal (M in the figure), changes the pulse width of the PWM modulation circuit 6, and generates a PWM modulated wave (the second half of b in the figure).
is creating. The audio subcarrier signal, which is the output of the PWM modulation circuit 6 and which has been PWM-modulated by audio in this way, is applied to the input of the NAND circuit 10 through the switch S2.

A signal is then sent out from the antenna 8 in the same process as when the pulse data signal is input. After a certain period of time, the output e of the pulse data generation circuit 3 returns to its original state, the switch S2 is turned off, and audio transmission is stopped.

Next, the receiver obtains a reproduced pulse data signal from the transmitter from the received signal in the same way as in the past, and sends it to the pulse data demodulation circuit 27, where it is compared with pre-stored pulse data, and when they match, it is output to the output terminal. Output the output signal to. Thereafter, when the input pulse data signal disappears, the squelch circuit 29 is operated for a certain period of time (the same time as the audio signal is sent from the transmitter, or a slightly shorter period of time), and the audio amplification circuit 30 is turned on.

On the other hand, the audio subcarrier signal shaped into a square wave by the waveform shaping circuit 26 is demodulated into an audio signal by the PWM demodulation circuit 28.
The voice is amplified by the voice amplification circuit 30 and is emitted from the speaker 32.

In the above embodiment, a method was described in which voice transmission is performed when there is input information, but the timing of both may be determined by various other methods.

[Effects of the Invention] As described above, according to the present invention, by adding an audio modulation circuit to the transmitter and an audio demodulation circuit to the receiver of a conventional wireless notification device, it is possible to transmit audio information. Because of this configuration, it is possible to create a device with an additional function of voice transmission at a low cost without compromising compatibility with conventional wireless notification devices that cannot transmit voice.

[Brief explanation of drawings]

1 and 2 are block diagrams respectively showing a transmitter and a receiver of a wireless notification device according to the present invention,
FIG. 3 is a timing diagram of a transmitter according to the present invention, FIGS. 4 and 5 are block diagrams of a transmitter and a receiver of a conventional wireless notification device, respectively, and FIG.
This figure is an operation timing diagram of the conventional transmitter shown in FIG. 4. 2...Crystal oscillation circuit 3...Pulse data generation circuit 4...Current amplification circuit 8...Antenna circuit 9...Battery 10... NAND circuit 11... Switching circuit 12... Oscillation circuit 20... Antenna circuit 26... Waveform shaping circuit 27... Pulse data demodulation circuit 28...
・PWM demodulation circuit 29...Squelch circuit 30...Audio amplification circuit 32...Speaker agent Patent attorney Moritani Figure procedure amendment Cjf. 1. Indication of the case Japanese Patent Application No. 62-134604 2 Name of the invention Wireless notification device 3 Person making the amendment Relationship to the case Patent applicant Aiphone Co., Ltd. 4 Date of amendment order August 25, 1986 (shipment date) 5. Agent 〒103 6. Subject of amendment

Claims (1)

[Claims] A wireless notification device that transmits a security signal based on a sensor output to the notification device main body side using a wireless transmitter at an appropriate transmission frequency, comprising: a source oscillation circuit, an oscillation circuit that oscillates at a frequency close to the transmission frequency, and the security signal. If the source oscillation circuit n times the oscillation frequency of (n=
2, 3, 4...) to the transmitter that provides the transmission frequency,
A wireless notification device characterized by adding an audio modulation circuit and an audio demodulation circuit to a receiver.