JPH01288024A - Radio selective call receiver - Google Patents

Abstract

PURPOSE:To adjust the sound volume of a receiver at all times to an optimum level automatically according to the quantity of surrounding noise by using a voice output and employing a sound ringing speaker as a microphone. CONSTITUTION:The surrounding noise signal is fetched at a prescribed time interval via a speaker 22, the signal is subject to holding on each occasion by a holding circuit 25 and a digital signal in response to the noise level is outputted toward an input control circuit 19 from a comparator circuit 26. Thus, the sound volume level of a ring tone and a voice message outputted from a radio circuit 18 is controlled to be small when the surrounding noise is large and to be large when the noise is small automatically based on the digital signal to be inputted, and the result is outputted to an amplifier circuit 20. When the speaker and the amplifier circuit 20 are connected, the ring tone and the voice message outputted from the radio circuit 18 are outputted from the speaker 22 while being controlled to an optimum sound volume level in matching with the surrounding noise.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a radio selective calling receiver having a tone function and a function of outputting a voice message following the tone.

[Prior Art] Today, portable wireless selective calling receivers are widely used for calling outside salespeople and people who go out frequently. A ring-only model that uses a loudspeaker to ring the subscriber (specific number assigned to the subscriber);
Services that add message information at the same time as a call,
There are models that provide a voice message service at the same time as a call.

By the way, since such a receiver is carried around as a portable device, the environment in which it is used varies, and may be used in a lively and noisy place or in a quiet place.

Therefore, such a receiver is required to have a function of appropriately adjusting the output volume level of sounds and messages according to the surrounding environment.

Normally, the volume of the ringing tone is often manually adjusted by the user each time.

FIG. 5 shows an example of such a volume switching mechanism by manual adjustment, and FIG. 3 shows such a switching mechanism 1a.
An electrical diagram of the structure is shown. 1 is the receiver body, 2 is a sound output slit for a speaker that outputs sound, and 3 is a slide switch that changes the volume and also serves as a power switch.

Also, in the same figure, 8 is a speaker, 9 is an amplification section, and 10 is a speaker.
11 is a wireless unit, and 12 is a battery.

In this figure, the slide switch 3 is in the volume rate state. The user selects large or small using the slide switch 3.

FIG. 2 is an example of a receiver that outputs a message in the form of voice after a sound. FIG. 3 is a circuit diagram of the volume control.

In the figure, 4 is the receiver body, 5 is a reset switch, 6 is a volume that continuously adjusts the volume, and 7 is a slit for producing sound from a speaker.

Further, in FIG. 3, 13 is a speaker, 14 is a power supply and volume adjustment switch, 15 is an amplification section, 16 is a wireless section, and 17 is a battery. In this receiver, the volume level of the sound or message can be adjusted by adjusting the volume 6 according to the user's preference.

However, with such conventional receivers, it is cumbersome for the user to manually adjust the volume, and once the adjustment is completed, the volume level is fixed until the user resets it. However, there was a problem in that it was not possible to respond flexibly to changes in the surrounding environment.

Furthermore, when mechanical parts such as a switch or a volume are used to adjust the volume, there is a problem in that these mechanical parts may become loose or damaged due to aging.

For this reason, in recent years, a type of receiver that automatically adjusts the volume level according to the surrounding environment has been developed, and this type of receiver uses a dedicated microphone to detect surrounding noise. .

However, when a dedicated microphone is used for noise detection, this microphone must be mounted within the limited space of the receiver, which makes the receiver large and heavy, which is required to be small and lightweight for portable use. Moreover, there was a problem in that it was expensive.

[Problems to be Solved] The present invention was made in view of these conventional problems, and its purpose is to provide a small and lightweight wireless selective calling device that can automatically adjust the volume level according to the surrounding environment. 9 [Means for solving problems] in providing a receiver
The wireless selective calling receiver of the present invention is a wireless selective calling receiver having a ringing function and a function of outputting a voice message following the ringing, and is configured to output a ringing sound and a voice message following the ringing. , a microphone-cum-speaker into which ambient noise is input; and a volume control circuit that controls the volume level of the @ sound and voice message input to the speaker based on the noise input from the microphone-cum-speaker. It is configured.

[Example code] Next, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a preferred example of a selective call receiver according to the present invention, in which 18 is a radio circuit, 20 is an amplifier circuit, 21 is an input/output switching circuit, 22 is a speaker, 27 is a control circuit, 28 2 is an amplifier circuit output line, 2 is a preamplifier circuit input line, 30 is a control circuit input line of the input/output switching circuit, 31 is a comparator output line, 32 is a sound output line, 33 is a radio circuit output line, 100 is a This is a volume level control circuit.

In this embodiment, this volume level III control circuit 100
are input control circuit 19, preamplifier circuit 23, A-D converter #124, hold circuit 25, comparator circuit 26
The output of the comparator circuit 26 is input to the input control circuit 19 via a comparator output line 31.

When the receiver of the embodiment receives its own calling signal, it inputs the output signal of the control circuit 27 to the input control circuit 19 via the sound line 32, and also inputs the output signal of the control circuit 27 to the input control circuit 19 via the sound line 32.
8 output signal is input to the VTM circuit 19 via line 33.
Output direction.

This input control circuit 19 is connected to the comparator circuit 2.
Based on the output signal of 6, the signal level of the sound signal and voice message inputted from the radio circuit 18 is controlled and outputted to the amplifier circuit 20.

This amplifier circuit 20 amplifies the input signal and outputs it to the input/output switching circuit 21.

The input/output switching circuit 21 controls whether the speaker 22 functions as a speaker or not according to a control signal from the control circuit 27.
Select whether to function as a microphone.

Therefore, when a signal instructing the speaker is output from the control circuit 27, the input/output switching circuit 21 outputs the output of the amplifier circuit 20 to the speaker 22, and the speaker 22 performs its original function, that is, the speaker function as Further, when a signal instructing the use as a microphone is output from the control circuit 27, the speaker 22 and the preamplifier circuit 23 are connected, and the amplifier circuit 20 is disconnected from the speaker 22. As a result, the speaker 22 is It functions as a microphone into which ambient sounds are input, and the input audio signals are outputted to the amplification circuit 23.

That is, when the speaker 22 is used as a microphone, noise around the receiver is input from the speaker 22 to the volume level control circuit 100 via the input/output switching circuit 21.

In the present invention, the volume level control circuit 100 is configured to control the input control port 819 according to the input noise signal, and adjust the volume level of the sound and voice message output from the wireless circuit 18 to an optimal state. has been done.

That is, the noise signal input from the speaker 22 to the preamplifier circuit 23 is amplified by this i-preamplifier circuit 23, and
- The D conversion circuit 24 converts the AC signal into a DC signal,
It is held by the hold circuit 25. The hold signal of this hold circuit 25 is several milliseconds from the control circuit 27.
It is sequentially updated by a clock output from ec to several hundred seconds.

The signal (DC voltage) held and output from the hold circuit 25 is converted into a 1-bit or multiple-bit binary digital signal by a comparator 26 and output to the input control circuit 19.

In this way, in the receiver of this embodiment, the speaker 32
Ambient noise signals are taken in at regular time intervals through a hold circuit 25 and held each time in a hold circuit 25, and a digital signal corresponding to the noise level is output from a comparator circuit 26 to an input control circuit 19.

Therefore, the input control port FN119 adjusts the volume level of the sound and voice message outputted from the wireless circuit 18 based on the digital signal inputted in this manner to a low level when the surrounding noise is large, and a low volume level when the surrounding noise is small. is largely automatically controlled and output to the amplifier circuit 20. Therefore, when the speaker and the amplifier circuit 20 are connected by the switching signal from the control circuit 27, the sound and voice messages output from the wireless circuit 18 are controlled to the optimum volume level in accordance with the surrounding noise. Then, it will be output from the speaker 22.

FIG. 6 shows an embodiment of the input/output switching circuit 21, where 38 is a terminal for a demodulation signal or sound signal sent from the amplifier circuit 20, and 39 is an input/output control signal terminal sent from two control circuits. , 40 are noise signal output terminals when the speaker 22 is operating as a microphone. 35 and 37 are transfer gates, and an inverter 36 is installed on the 35 side, and 35 and 37 have opposite logics.

FIG. 7 shows a timing chart of the circuit shown in FIG.

42 is a demodulation or sound signal entering the transfer gate 35, and 43 is an ambient noise signal when operating as a microphone. 44 is a control signal coming from the control circuit 27, and the transfer gate is turned on at H level and turned off at L level.
Performs an action that becomes FF. 45 is a waveform output to the speaker terminal 41, and 46 is a signal appearing at the microphone output terminal 40.

This figure shows an operation that starts at timing T1, the control signal 44 turns ON, and the transfer gate 35 turns ON, and the control signal 44 turns H at timing T2, turning the transfer gate 37 ON. That is, T
From T2 to T2, it works as a speaker, and after T2, it works as a microphone.

FIG. 8 shows an example of the A-D conversion circuit 24.

The noise level amplified to a level that does not saturate in the preamplifier circuit 23 enters the input terminal 54 of the A-D converter circuit 24.
After passing through a buffer amplifier 47 to lower its impedance, it is converted into direct current by a rectifying and smoothing circuit composed of a capacitor 48.51 and a diode 49.50. The DC signal is divided by resistors (R, R) 52.53, and an output voltage given by R2·V/(R+R2) is generated at the output terminal 55.

This output is output to the hold circuit 25 at the next stage.

FIG. 9 shows an example of the hold circuit 25.

The hold circuit 25 includes two buffer amplifiers 57.60
, transfer gate 56, capacitor 58, resistor 5
Consists of 9.

The output from the A-D conversion circuit 24 is input to the input terminal 61 . A timing signal is input from the control circuit 27 to the control input terminal 62 . The DC signal input to the input terminal is turned ON when the timing signal is input, and is connected to the buffer amplifier 57. The capacitor 58 connected to the output side of the buffer amplifier 57 holds the potential for a while until the next clock is input even if the timing signal becomes L and the transfer gate 56 is turned off. Furthermore, the signal enters another stage of buffer 60 through a resistor 59 and outputs to an output terminal 63 after lowering the impedance.

FIG. 10 is a timing chart showing the operation of the hold circuit 25 described above. 64 is a DC input, 65 is a timing signal, and 66 is an output.

In this figure, the input voltage is updated at timings T1 to T4 by timing signals output at intervals T, and is held until the next timing signal arrives.

FIG. 11 is an example of the comparator circuit 26.

In this example, two comparators 6 converting to 2 bits
7.68 and dividing resistor 69.70.71 and reference voltage 7
The DC signal input to the input terminal 75 is input to each comparator. The comparator 67 is
If the voltage obtained by dividing the Vs■ reference voltage 67 by the bleeder resistor is ■A1, then vA1=(R2+R3)■s[/(
Compare the voltage represented by R1+R2+R3) with the input.

The other comparator 68 is V = R-VST/ (R1+ R2+ R3>^2
3 Compare the voltage represented by and the input.

However, let VA2<VAl.

FIG. 12 is a timing chart showing this operation. A comparator operates according to the voltage of the input cuff 6,
The output shown at 77.78 is obtained.

FIG. 13 shows an example of the input control circuit 19.

In this example, the input I11 control circuit 19 includes three transfer gates 79, 80, 81 and three resistors 82.
．． 83, 84 and a binary to decimal counter 85.

The comparator circuit 26 is connected to the input terminals 93 and 94.
The counter 85 receives output signals from the counter 85, converts these two signals from binary to decimal, and operates to set one of the counter outputs to H level. The truth table for this is number 17.
As shown in the figure.

There are three transfer gates 79, 80, 81 at the output of the counter 8, and the level of the output from the radio section or the sound signal from the AF input terminal 87 is changed by resistors 82, 83, 84, respectively. The signal is received.

The AP large input enters the transfer gate 75 as it is, and the transfer gate 80 receives ■ = (R2+R
3) VAF F2 / (R1 + R2 + R3) Transfer gate 81 has V = R - V / (R1 + R2 + R3) AF3
The output given by 3 AF will be output.

These three outputs are controlled by input signals 93.94. The (1, 0) output of the counter output is not used here, but it is used in the comparator circuit described above (1, 0).
0).

FIG. 14 is an example of a flowchart showing the operation of the control circuit 27.

As described above, by combining these circuits, it is possible to control the volume of the output sound and voice message according to the amount of ambient noise.

Figures 15 and 16 show changes in the appearance of receivers that no longer require volume setting, and in both cases there are no or fewer moving parts.

[Effects of the Invention] As explained above, the present invention improves the conventional method by using the speaker for audio output and sound as a microphone.
It is possible to detect ambient noise and automatically adjust the volume of the receiver to the 8-week level according to the level of ambient noise without using a dedicated microphone installed in the limited space inside the small receiver. You can get a small, lightweight wireless selective call receiver that can.

[Brief explanation of the drawing]

Fig. 1 is a block circuit diagram of a receiver according to the present invention, Fig. 2 is an external view of a conventional receiver that emits a sound as well as a voice message based on the sound, and Fig. 3 shows the reception shown in Fig. 5. Figure 4 is a block circuit diagram of the volume adjustment part of the receiver shown in Figure 2. Figure 5 is an external view of a conventional receiver that produces sound, including the volume setting part. Figure 6 is an input/output switching circuit diagram; Figure 7 is a time chart showing the operation of the input/output switching circuit; Figure 8 is an A-D conversion circuit diagram; Figure 9 is a hold circuit diagram; The figure is a time chart diagram showing the operation of the hold circuit, Figure 11 is a comparator circuit diagram, Figure 12 is a time chart diagram showing the operation of the comparator circuit, Figure 13 is an input control circuit diagram, and Figure 14 is a control circuit diagram. A flowchart diagram showing the operation of the circuit. Fig. 15 is an external view of a receiver that emits a sound according to the present invention. Fig. 16 is an external view of a receiver that emits a sound according to the present invention and also outputs a voice message following the sound. Figure 17 is
FIG. 3 is an explanatory diagram of a truth table showing the operation of the input control circuit. 100: Volume level control circuit representative Patent attorney Kihei Watanabe Figure 2 Figure 4 A Figure 8 Figure 9 ffi (Tl l"')
Figure 10 Figure 11 Figure 12 ime Figure 13 Figure 14

Claims (1)

[Claims] (1) In a wireless selective calling receiver having a ringing function and a function of outputting a voice message following the ringing, the receiver is configured to output a ringing tone and a voice message following the ringing, and at the same time inputs ambient noise. Wireless selective call reception characterized by comprising: a speaker that also serves as a microphone; and a volume control circuit that controls the volume level of the sound and voice message input to the speaker based on the noise input from the speaker that also serves as a microphone. Machine.