JPH0569331B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a wireless notification device capable of selectively transmitting audio.

[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 which 1 is an input terminal that receives a transfer signal from an external sensor means, etc. The signal is input to a pulse data generation circuit 3, which outputs determined pulse code data upon receiving the transfer signal based on the clock signal of the crystal oscillation circuit 2 as a source oscillation circuit.

The output of the pulse data generation circuit 3 and the pulse output of the crystal oscillation circuit 2 are NANDed, and when the output pulse data signal of the pulse data generation circuit 3 is in the "H" state, the output signal of the crystal oscillation circuit 2 is Gate operation to be transmitted to the switching circuit 11 of the stage
Insert the NAND circuit 10, and this NAND circuit 10
Switching circuit 1 that controls on/off of the oscillation operation of the next stage LC oscillation circuit 12 by the output signal of
1 will be provided.

The LC oscillation circuit 12, 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, outputs an oscillation output n times the oscillation frequency _XT of the source oscillation circuit to the next circuit composed of the transistor _Q4 . The amplified signal is applied to the amplifier circuit 7 of the stage, and the amplified signal is radiated into the air via the antenna circuit 8. Note that 9 indicates 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 FIG. 5, reference numeral 20 denotes a receiving antenna, which receives the battery that carries the shifting information from the transmitting antenna 8 and applies it to the high frequency amplification circuit 21, and the signal amplified here is sent to the local oscillation circuit 23 and the frequency mixing circuit. 2
2 into an intermediate frequency signal, this signal is amplified by an intermediate frequency amplification circuit 24 and then AM detected by an AM detection circuit 25. The configuration and operation up to this point are the same as those of 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.

Here, the operation of the transmitter of the radio reporting device configured as described above will be explained below with reference to the operation timing diagram of FIG. 6.

When there is no notification signal input to the input terminal 1 (FIG. 4) (for example, the input is in the "L" state), the output of the pulse data generation circuit 3 is in the "L" state, and the NAND circuit 10
Since the output of is in the "H" state, the switching transistor _Q5 of the switching circuit 11 is in the on state, and the emitter potential of the oscillation transistor _Q6 of the LC oscillation circuit 12 is rising, causing the opposite Since it is in a bias state, oscillation has stopped.

Next, when a notification signal is input to the input terminal 1 (for example, input "H" state), predetermined pulse data is output from the output of the pulse data generation circuit 3 (b in Figs. 4 and 6). ), when the same output is in the "H" state, the oscillation output signal (a in Figures 4 and 6) of the crystal oscillation circuit 2 as the source oscillator is output from the NAND circuit 1.
It passes through 0 and is output in an inverted form (Fig. 4, c in Fig. 6). That is, the pulse data generation circuit 3
output (Fig. 4, b in Fig. 6) and crystal oscillation circuit 2
Both outputs (a in Figures 4 and 6) are "H"
In this state, the output of the NAND circuit 10 becomes "L" state (Fig. 4, c in Fig. 6), and at this time, the switching transistor _Q5 of the switching circuit 11
turns off, and the oscillation transistor _Q6 of the LC oscillation circuit 12 is normally biased and enters the oscillation state (d in FIGS. 4 and 6).

In the circuit configured in this manner, the oscillation frequency ₀ of the LC oscillation circuit 12 oscillates at n times the oscillation frequency _XT of the crystal oscillation circuit 2 (n=2, 3, 4, . . . ). That is, ₀ = n・_XT However, ₀ is the oscillation frequency of the LC oscillation circuit 12, _XT
is the oscillation frequency of the crystal oscillation circuit 2, n=2, 3,
4...is. However, the conventional wireless reporting device configured as described above has a drawback in 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 a pulse code (PCM), making the device extremely expensive.

[Object of the Invention] The present invention has been made in view of the above circumstances, and enables selective transmission of voice information, and provides an additional function of voice transmission without compromising compatibility with conventional wireless notification devices that cannot transmit voice. The aim is to realize this with a simple circuit configuration.

[Summary of the Invention] In order to achieve this object, the present invention includes a source oscillation circuit that generates a clock signal, and a clock signal of the source oscillation circuit that is input and pulse data that is determined by receiving a security signal from a sensor output. The clock signal of the output pulse data generation circuit, the amplifier circuit that amplifies the audio signal input from the microphone, the audio modulation circuit that modulates the amplified audio signal, and the source oscillation circuit is input to one input terminal. A switch connected between the gate circuit and the other input terminal of the gate circuit and the pulse data generation circuit, which is turned on when pulse data is being output and turned off when it is not, and when pulse data is being output. a switch connected between the other input terminal of the gate circuit and the audio modulation circuit, which is turned on when it is turned off and not outputting;
A switching circuit to which the output from the gate circuit is applied, and an on-off control controlled by the switching circuit, which is n times the oscillation frequency of the source oscillation circuit (n=2,
The transmitter is equipped with an oscillation circuit that provides a transmission frequency of A receiver is equipped with a pulse data demodulation circuit that outputs, an audio demodulation circuit that demodulates the audio modulation signal sent from the transmitter, and a squelch circuit that is activated and turned on when the pulse data demodulation circuit runs out of pulse data. It was established.

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

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, and the same elements as those in FIGS. 4 and 5 are the same. It is marked with the symbol.

The difference between the transmitter of the wireless notification device of this embodiment and the conventional device shown in FIG. A square wave audio subcarrier determined by the current amplifier circuit 4 consisting of the source transistor _Q1 and the external capacitor C is output.
This is because the PWM modulation circuit 6 is provided.

In this case, the repetition period of the output audio subcarrier is determined by the frequency of the clock pulse input from the crystal oscillation circuit 2 via the frequency dividing circuit 5.

Furthermore, in the current amplifier circuit 4, the audio signal input from the microphone M is input to the base of the transistor _Q1 , a changed current signal is obtained from the collector, the pulse width is changed by the PWM modulation circuit 6, and a PWM modulated wave is generated. is creating.

Further, a switch S ₁ is provided between the pulse data generation circuit 3 and the NAND circuit (gate circuit) 10,
PWM modulation circuit 6 and NAND circuit (gate circuit)
A switch _S2 is provided between 10 and 10 to take the timing. In addition, in FIG. 1, 9 indicates a battery that energizes the circuit elements.

Furthermore, the receiver of this embodiment (FIG. 2) differs from the conventional device (FIG. 5) in that the regenerated pulse data signal from the waveform shaping circuit 26 is sent to the pulse data demodulation circuit 27 as in the conventional case. In addition to comparing the pulse data added and stored in advance and outputting an output signal to the output terminal 31 when they match,
A PWM demodulation circuit 28 that receives the audio subcarrier signal shaped into a square wave by the waveform shaping circuit 26 and restores it to an audio signal, and an amplifier 30 that amplifies this audio signal.
and a speaker 32 that outputs this as audio.

After the pulse data demodulation circuit 27 outputs the output signal to the output terminal 31, the audio amplification circuit 30
When the input pulse data signal disappears, the squelch circuit 29 is operated and turned on for a certain period of time (same or slightly shorter period of time as the audio signal is sent from the transmitter).

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.

The output signal (a in Fig. 3) of the crystal oscillator circuit 2 (Fig. 1) is applied to one input a of the NAND circuit (Fig. through 5
It is applied to the PWM modulation circuit 6 as a clock signal for subcarrier generation.

When a transfer signal (IN in Figs. 1 and 3) 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 (1 Figure 3c) is output.

While this pulse data signal is being output, the state of the output d of the pulse data generation circuit 3 changes (d in Figures 1 and 3), and the switch _S1 is turned on.
The pulse data signal passes through this switch _S1 .
It is applied to input b of the NAND circuit (gate circuit) 10 (the first half of b in FIGS. 1 and 3).

Of the pulse data signals input to this input b, only when the signal is in the "H" state, the output signal of the crystal oscillation circuit 2 applied to the input a is inverted and output (see FIG. g) in Figure 3. below,
As in the conventional example, the output signal is sent to the switching circuit 11.
The oscillation operation of the oscillation circuit 12 consisting of the transistor Q ₃ is controlled on/off through the switching transistor Q ₂ of the transistor Q 2 to obtain a transmission frequency n times (n = 2, 3, 4, etc.) (Fig. 1, Figure 3 h).

After the output c of the pulse data signal from the pulse data generation circuit 3 is completed, the output d returns to its original state and the switch _S1 is turned off (d in FIG. 3). At the same time, the state of the output e changes (Fig. 1, 3
Figure e) 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 crystal oscillator circuit 2 via the frequency divider circuit 5 (Fig. 3), and its pulse width is determined by the current amplification circuit 4 as a constant current source and the external capacitor C as described above. In addition, as described above, the current value of the current amplifier circuit 4 changes depending on the audio signal (M in FIG. 3) input from the microphone M, thereby changing the pulse width of the PWM modulation circuit 6.
It creates a PWM modulated wave (the second half of M in Figure 3). 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 b of the NAND circuit (gate circuit) 10 through the switch _S2 . The output g of the NAND circuit (gate circuit) 10 is connected to a switching circuit 11 consisting of a switching transistor _Q2 ,
The signal is inputted via the oscillation circuit 12 made up of the transistor _Q3 and the amplifier circuit 7 made up of the transistor _Q4 , and is sent out from the antenna 8 in the same process as when inputting the pulse data signal. After a certain period of time, the output e of the pulse data generation circuit 3 returns to its original state,
Switch _S2 turns off and stops transmitting audio. In this way, audio is selectively transmitted from the transmitter to the receiver.

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. After that, when the input pulse data signal disappears, the squelch circuit 29
is operated 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) to turn on the audio amplification circuit 30.

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, amplified by the audio amplification circuit 30, and audio is emitted from the speaker 32.

Although this embodiment has been described using a method in which audio is transmitted when input information is received, the timing of both may be determined by various other methods.

[Effects of the Invention] As is clear from the above description, the wireless notification device of the present invention includes a source oscillation circuit that generates a clock signal, and a clock signal of the source oscillation circuit that is input and receives a security signal from the sensor output. The clock signal of the source oscillator circuit is connected to the pulse data generation circuit that outputs pulse data determined by A gate circuit input to the input terminal of the gate circuit, a switch connected between the other input terminal of the gate circuit and the pulse data generation circuit, which is turned on when pulse data is being outputted and turned off when not outputted, and the pulse A switch connected between the other input terminal of the gate circuit and the audio modulation circuit that is turned off when data is being output and turned on when data is not being output, a switching circuit to which the output from the gate circuit is applied, and a switching circuit. The transmitter is equipped with an oscillation circuit that is controlled on and off by the oscillation circuit and provides a transmission frequency that is n times (n = 2, 3, 4...) the oscillation frequency of the source oscillation circuit, and the pulse data signal sent from the transmitter is A pulse data demodulation circuit that compares with pre-stored pulse data and outputs an output signal to the output terminal when they match, an audio demodulation circuit that demodulates the audio modulation signal sent from the transmitter, and a pulse data demodulation circuit. By equipping the receiver with a squelch circuit that is activated and turns on when pulse data disappears from the receiver, it is possible to selectively transmit audio information, thereby increasing compatibility with conventional radio reporting devices that cannot transmit audio. The additional function of voice transmission can be realized with a simple circuit configuration.

[Brief explanation of drawings]

1 and 2 are block diagrams showing a transmitter and a receiver of a wireless notification device according to the present invention, respectively, FIG. 3 is a timing diagram of a transmitter according to the present invention, and FIGS. 4 and 5 are respectively FIG. 6 is a block diagram of a transmitter and a receiver of a conventional wireless notification device, and FIG. 6 is an operation timing diagram of the conventional transmitter shown in FIG. 2...Crystal oscillation circuit (source oscillation circuit), 3...Pulse data generation circuit, 4...Amplification circuit, 6...Audio modulation circuit, 10...NAND circuit (gate circuit), 11...Switching circuit, 12...Oscillation circuit, 27... Pulse data demodulation circuit, 28...PWM demodulation circuit, 29...
Squelch circuit, S ₁ ... switch, S ₂ ... switch, M
...Microphone.

Claims (1)

[Claims] 1. A source oscillation circuit 2 that generates a clock signal, and a pulse data generation circuit 3 that receives the clock signal of the source oscillation circuit, receives a security signal from a sensor output, and outputs determined pulse data.
, an amplifier circuit 4 that amplifies the audio signal input from the microphone M, an audio modulation circuit 6 that modulates the amplified audio signal, and a gate circuit to which the clock signal of the source oscillation circuit is input to one input terminal. 10, a switch _S1 connected between the other input terminal of the gate circuit and the pulse data generating circuit, which is turned on when the pulse data is being outputted and turned off when the pulse data is not being outputted; a switch _S2 connected between the other input terminal of the gate circuit and the audio modulation circuit, which is turned off when the output is being outputted and turned on when the output is not outputted; and a switching circuit 11 to which the output from the gate circuit is applied. and an oscillation circuit 12 which is controlled on and off by the switching circuit and provides a transmission frequency n times (n=2, 3, 4...) the oscillation frequency of the source oscillation circuit, and from the transmitter. A pulse data demodulation circuit 27 compares the sent pulse data signal with pre-stored pulse data and outputs an output signal to the output terminal when they match, and demodulates the audio modulation signal sent from the transmitter. 1. A wireless reporting device characterized in that a receiver is provided with a voice demodulation circuit 28 for generating a signal, and a squelch circuit 29 that is activated and turned on when pulse data is lost from the pulse data demodulation circuit.