JPH07321683A - Receiver circuit and its control method - Google Patents

Abstract

PURPOSE:To obtain a receiver circuit and its control method realizing the saving of power consumption in an audio amplifier through comparatively simple circuit configuration. CONSTITUTION:An audio detection section 11 detects an audio signal outputted from a demodulation section 3 on the condition that an electric field strength detection section 10 detects the electric field strength of a specific level from the signal of a high frequency amplifier section 1 and the electric field strength detection section 10 receives a signal representing the detection of an electric field strength of a specific level or over. Then a timer section 12 controls a power on/off signal turning on/off a power supply of an audio amplifier section 6 based on a signal representing electric field strength detection and the audio detection signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver circuit using a super-heterodyne system used in a portable receiver or the like, and more particularly to a receiver circuit capable of saving power consumption and its control method.

[0002]

2. Description of the Related Art First, a conventional receiver circuit will be described with reference to FIG. FIG. 3 is a configuration block diagram of a conventional receiver circuit. As shown in FIG. 3, a receiver circuit using a conventional super-heterodyne system includes an antenna 7, a high frequency amplification unit 1, an intermediate frequency amplification unit 2, a demodulation unit 3, a noise squelch unit 4, and a switch unit. 5, an audio amplifier section 6, and a speaker 8. For general receiver circuits, see “Mobile Communication, Masaaki Shinji 19
89.9.30 Published by Maruzen Co., Ltd., p215-p242 ".

The connection relationship between the respective parts is that the received signal received by the antenna 7 is input to the high frequency amplifier 1, the output of the high frequency amplifier 1 is input to the intermediate frequency amplifier 2, and the output of the intermediate frequency amplifier 2 is input. Is input to the demodulation unit 3, one output of the demodulation unit 3 is input to the noise squelch unit 4, and the control signal output from the noise squelch unit 4 is input to the switch unit 5. Further, the other output of the demodulation unit 3 is input to the audio amplifier unit 6 via the switch circuit 5, the output of the audio amplifier unit 6 is input to the speaker 8, and the sound received from the speaker 8 is output. It has become.

Next, the operation of each part of the conventional receiver circuit will be specifically described. The antenna 7 receives a high frequency radio signal in radio communication, and the high frequency amplifier 1
Is for amplifying the high frequency signal received by the antenna 7.

The intermediate frequency amplifying section 2 is a section which converts the high frequency received wave amplified by the high frequency amplifying section 1 into an intermediate frequency and amplifies it. Specifically, the output wave from the high frequency amplifying section 1 and a local part. The output wave from an oscillator (not shown) is mixed by a non-linear element to obtain an intermediate frequency which is a difference frequency (or a sum frequency) between the two, and thus frequency conversion is performed and this is amplified.

The demodulation section 3 is a section for demodulating the intermediate frequency amplified by the intermediate frequency amplification section 2. Specifically, the amplified intermediate frequency is band-pass filtered and band-limited, and then detected by a detector. The signal is demodulated into an audio frequency (low frequency) signal (audio signal).

Next, the audio amplifier section 6 includes a demodulation section 3
The amplifier 8 amplifies a voice frequency signal that is demodulated by the switch unit 5 and is input through the switch unit 5. The speaker 8 converts the voice frequency electric signal amplified by the audio amplifier unit 6 into a vibration of sound and outputs the vibration. To do.

On the other hand, the noise squelch section 4 and the switch section 5 may have very strong noise when there is no voice signal output from the demodulation section 3 or when the voice signal is extremely weak. The noise squelch unit 4 outputs a control signal for turning on / off the connection between the demodulation unit 3 and the audio amplifier unit 6 to the switch unit 5 depending on the presence / absence of an input signal in a portion that prevents noise from being output from the speaker 8. It is like this.

More specifically, the noise squelch unit 4 switches the switch circuit when an input signal having a predetermined level is not detected, noise exceeding a predetermined level is detected, or both of them. 5, a control signal for turning off the connection between the demodulation unit 3 and the audio amplifier 6 is output. On the contrary, when an input signal of a preset level is detected, a control signal for turning on the connection between the demodulation unit 3 and the audio amplifier 6 is output to the switch circuit 5. The switch unit 5 is configured to switch ON / OFF of the connection between the demodulation unit 3 and the audio amplifier unit 6 based on the control signal output from the noise squelch unit 4.

Next, regarding the operation of the conventional receiver circuit,
This will be described with reference to FIG. In the conventional receiver circuit, when the antenna 7 receives a transmission wave from a communication partner in wireless communication, the received high frequency signal is amplified by the high frequency amplification unit 1,
The intermediate frequency amplifier 2 converts the signal to an intermediate frequency for amplification, further demodulates it to an audio frequency, and outputs it to the noise squelch unit 4 and the switch unit 5.

At this time, the noise squelch section 4 detects that the input audio signal has reached a prescribed level and outputs an ON control signal to the switch circuit 5. Then, in the switch circuit 5, the noise squelch unit 5
The connection between the demodulation unit 3 and the audio amplifier 6 is switched to ON based on the ON control signal input from, and the audio frequency signal output from the demodulation unit 3 is input to the audio amplifier unit 6, and the audio amplifier unit 6 The amplified sound is output from the speaker 8.

On the other hand, in the wireless communication, when the communication with the other party is cut off or when the call is interrupted, the voice signal output from the demodulation section 3 to the noise squelch section 4 disappears. At this time, the noise squelch unit 4 detects that the input audio signal does not reach the regulated level, or detects that the noise exceeds the regulated level, and outputs an OFF control signal to the switch circuit 5. Is output. And
In the switch circuit 5, the connection between the demodulation unit 3 and the audio amplifier 6 is turned off based on the OFF control signal input from the noise squelch unit 5, and the noise signal output from the demodulation unit 3 is input to the audio amplifier unit 6. Therefore, noise is not output from the speaker 8.

[0013]

However, in the above conventional receiver circuit and its control method, when the voice signal from the communication partner disappears, the operation of the noise squelch unit 4 and the switch circuit 5 causes the demodulation unit 3 and the audio amplifier to operate. Part 6
However, the noise signal output from the demodulation unit 3 is not amplified by the audio amplifier unit 6 and output from the speaker 8, but the audio amplifier unit 6 is always operating and wasteful. There is a problem that it consumes a lot of power and cannot save power.

Further, if the conventional receiver circuit has a circuit configuration considering power saving, there is a problem that the circuit becomes complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a receiver circuit and a control method therefor capable of realizing power saving in an audio amplifier with a relatively simple circuit configuration. .

[0016]

According to a first aspect of the present invention for solving the above-mentioned problems of the conventional example, an electric field intensity detecting section for detecting an electric field intensity of a received signal in a receiver circuit,
A voice detection unit that detects a voice obtained by demodulating the received signal, and a timer that controls power on / off of an audio amplifier of a receiver based on the signal from the electric field strength detection unit and the signal from the voice detection unit. It is characterized by having a part.

According to a second aspect of the present invention for solving the problems of the conventional example, in the method for controlling a receiver circuit according to the first aspect, the signal from the electric field intensity detecting section is in a signal-present state, and a voice signal is output. It is characterized in that the timer unit turns on the power supply of the audio amplifier of the receiver when the signal from the detection unit has a signal.

According to a third aspect of the present invention for solving the problem of the conventional example, in the control method of the receiver circuit according to the first aspect, the signal from the electric field strength detection section is in a signal-present state, and the voice signal is output. It is characterized in that the timer unit turns on the power supply of the audio amplifier of the receiver for a specific time when the signal from the detection unit is in a non-signal state.

According to a fourth aspect of the present invention for solving the problems of the conventional example, in the control method of the receiver circuit according to the first aspect, the signal from the electric field strength detecting section is a voice signal, It is characterized in that the timer unit turns on the power supply of the audio amplifier of the receiver for a specific time when the signal from the detection unit is in a non-signal state.

According to a fifth aspect of the present invention for solving the problems of the conventional example, in the method for controlling a receiver circuit according to the first aspect, the signal from the electric field strength detection section is a voice signal and a voice signal is output. When the signal from the detection unit is in the state of no signal, the timer unit turns on the power of the audio amplifier of the receiver for a specific time, and after the specific time ends, the power of the audio amplifier is turned off. The timer section turns on the power supply of the audio amplifier of the receiver when the signal of (1) becomes a signal-present state.

[0021]

According to the first aspect of the invention, the electric field strength detection unit detects the electric field strength of the received signal, the voice detection unit detects voice, and the timer unit detects the signal from the electric field strength detection unit and the voice detection. Since it is a receiver circuit that controls the on / off of the power supply of the audio amplifier of the receiver by the signal from the section,
The power consumption of the audio amplifier can be saved.

According to the second aspect of the invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has a signal, the timer section operates in the audio amplifier of the receiver. Since the method of controlling the receiver circuit according to the first aspect of the present invention is to turn on the power supply, it is possible to realize power saving in the audio amplifier at times other than during a call.

According to the third aspect of the present invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has no signal, the timer section is set in the audio amplifier of the receiver. Since the method for controlling the receiver circuit according to claim 1 is to turn on the power supply for a specific time, it is possible to realize power saving in the audio amplifier.

According to the fourth aspect of the invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has no signal, the timer section is provided in the audio amplifier of the receiver. Since the method for controlling the receiver circuit according to claim 1 is to turn on the power supply for a specific time, it is possible to realize power saving in the audio amplifier.

According to the fifth aspect of the invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has no signal, the timer section operates in the audio amplifier of the receiver. The power source is turned on for a specific time, the audio amplifier is turned off after the specific time is over, and when the signal from the voice detection section has a signal present state, the timer section turns on the audio amplifier of the receiver. Since the receiver circuit control method described in 1 is used, it is possible to operate the audio amplifier in priority to the call state while realizing power saving in the audio amplifier.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a configuration block diagram of a receiver circuit according to an embodiment of the present invention. It should be noted that parts having the same configuration as in FIG.

As shown in FIG. 1, the receiver circuit of this embodiment has a high frequency amplification section 1, an intermediate frequency amplification section 2, and a demodulation section 3.
An audio amplifier section 6, an antenna 7, a speaker 8, and an electric field strength detection section 1 which is a characteristic part of this embodiment.
0, a voice detection unit 11, and a timer unit 12.

As for the connection relation of each part in the receiver circuit of this embodiment, as shown in FIG. 1, the signal received by the antenna 7 is input to the high frequency amplification part 1 and the high frequency amplification part 1
Is input to the intermediate frequency amplification unit 2 and the electric field strength detection unit 10, and the output of the intermediate frequency amplification unit 2 is input to the demodulation unit 3.
The output of the demodulation unit 3 is the audio amplifier unit 6 and the voice detection unit 1.
1, the output of the electric field strength detection unit 10 is input to the voice detection unit 11 and the timer unit 12, the output of the voice detection unit 11 is input to the timer unit 12, and the output of the timer unit 12 is a power ON / OFF signal. Is input to the audio amplifier unit 6, the output of the audio amplifier unit 6 is input to the speaker 8, and the voice is output from the speaker 8.

Next, each part of the receiver circuit of this embodiment will be specifically described. However, the high frequency amplification unit 1, the intermediate frequency amplification unit 2, the demodulation unit 3, the audio amplification unit 6, the antenna 7, and the speaker 8 are the same as those described in the conventional receiver circuit of FIG. The description is omitted.

The electric field strength detection unit 10 detects the electric field strength of the high frequency signal output from the high frequency amplification unit 1. Specifically, if the electric field strength of the high frequency signal is equal to or higher than a specific value, a high level signal is output to output a signal indicating a signal present state, and if the electric field strength of the high frequency signal is smaller than the specific value, it is Low. A level signal is output and a signal indicating a no signal state is output.

The voice detection unit 11 detects the voice signal output from the demodulation unit 3, and particularly detects the voice signal only when the electric field intensity detection signal from the electric field intensity detection unit 10 is input. It is something to do. That is, the voice detection unit 11 detects the voice signal from the demodulation unit 3 only when the signal output from the electric field strength detection unit 10 is at the high level. Then, the detection signal obtained by detecting the audio signal is output to the timer unit 12.

The timer section 12 receives the signal from the electric field intensity detecting section 10 and the signal from the voice detecting section 11 and outputs a power ON / OFF signal for controlling ON / OFF of the power source of the audio amplifier section 6. It is a thing.

Next, power ON / O in the timer section 12
A method of controlling the output state of the FF signal will be described with reference to FIG. FIG. 2 is a timing chart showing a correspondence relationship among the output signal from the electric field strength detection unit 10, the output signal from the voice detection unit 11, and the power ON / OFF signal to the audio amplifier unit 6.

First, the power of the audio amplifier section 6 is turned ON /
The processing state of the timer unit 12 that controls OFF is divided into four states, that is, state A, state B, state C, and state D. The operation of the timer unit 12 will be described below for each state.

The state A means that the output signal from the electric field strength detection unit 10 is in the signal presence state (High level) and the output signal from the voice detection unit 11 is in the signal presence state (High level). , Power ON / OFF signal ON
(High level) state. This corresponds to a normal call state, and it is natural that the power source of the audio amplifier unit 6 is turned on when the electric field strength is equal to or higher than a specific value and there is a voice signal. This is a priority operation.

In the state B, when the output signal from the electric field strength detection unit 10 is in the signal presence state (High level), but the output signal from the voice detection unit 11 is in the signal absence state (Low level), The power ON / OFF signal is kept in the ON (High level) state for a certain time t after the output signal from the electric field strength detection unit 10 becomes the High level, and is kept in the OFF (Low level) state after the time t ends. is there. This corresponds to a state in which the other party is transmitted without speaking, there is no voice, and the electric field strength is equal to or higher than a specific value. In this case, even if there is no voice, the other party is likely to start speaking immediately, so the power of the audio amplifier unit 6 is turned on for a time t.

State C is a state in which the output signal from the electric field strength detection unit 10 has a signal (high level), and the output signal from the voice detection unit 11 has a signal (high level).
When the state is changed to the no signal (Low level) state, the power ON / OFF signal is turned ON for a certain time t after the output signal from the voice detection unit 11 becomes the Low level.
Set to N (High level) state and turn off after the end of time t
(Low level) state. This corresponds to the case where the other party stops the call during transmission, and is the case where the voice is not detected when the electric field strength is equal to or higher than the specific value. In this case, even if the voice disappears, the other party is likely to start talking again, so the power supply of the audio amplifier unit 6 is turned on for the time t.

In the state D, when the time t in the state C ends and the power ON / OFF signal is turned OFF, the output signal from the voice detection unit 11 changes from the signal non-state (Low level) to the signal present (Low level). The power ON / OFF signal is immediately turned to the ON (High level) state when the state is changed to the (High level) state. This corresponds to the case where the other party interrupts and resumes the call during transmission, and is a case where the electric field strength is equal to or higher than the specific value and the voice is not detected once and the voice is detected again. In this case, the call is not resumed within the time t, but when the call is started, the power of the audio amplifier unit 6 is immediately turned on as in the state A.

Although not shown in the figure, the call is resumed within the time t of the state C, and the signal from the voice detecting section 11 is detected (H
When it is in the (high level) state, the state A is preferentially realized in order to output the sound from the speaker 8. That is, if the signal from the voice detection unit 11 is brought into the high level state within the time t, the power source of the audio amplifier unit 6 is kept ON.

In the above embodiment, the times t of the states B to D are the same time, but it is also possible to optimize each state and set different times t.

According to the receiver circuit and its control method of the present embodiment, during the call in the state A, the control signal for turning on the power supply of the audio amplifier section 6 is outputted from the timer section 12 so that the voice can be outputted. Therefore, the control signal for turning on the power supply of the audio amplifier unit 6 only during the time t in the state B in which nothing is spoken is output from the timer unit 12 so that the next call can be handled. Even when the call in the state C is interrupted, the audio amplifier unit 6 is operated only for the time t.
The control signal for turning on the power supply of is turned on from the timer unit 12 so as to be ready for the next call. When the call is restarted after the time t of the state D, the audio amplifier unit 6 is immediately started.
Since the control signal for turning on the power of the device is output from the timer unit 12 to output the sound, the power consumption of the audio amplifier unit 6 can be suppressed and the power saving of the receiver can be realized. By using the ON / OFF control, it is possible to prevent the power of the audio amplifier unit 6 from being frequently turned ON / OFF.

[0042]

According to the invention described in claim 1, the electric field strength detecting section detects the electric field strength of the received signal, the voice detecting section detects voice, and the timer section detects the signal from the electric field strength detecting section and the signal from the electric field strength detecting section. Since the receiver circuit controls ON / OFF of the power supply of the audio amplifier of the receiver by the signal from the voice detection unit, there is an effect that the power consumption of the audio amplifier can be saved.

According to the second aspect of the present invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has a signal, the timer section is provided in the audio amplifier of the receiver. Since the method of controlling the receiver circuit according to the first aspect of the present invention is to turn on the power supply, there is an effect that power consumption of the audio amplifier can be saved when not in a call.

According to the third aspect of the present invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has no signal, the timer section is set in the audio amplifier of the receiver. Since the receiver circuit is controlled by turning on the power supply for a specific time, there is an effect that the power consumption of the audio amplifier can be saved.

According to the fourth aspect of the present invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has no signal, the timer section operates in the audio amplifier of the receiver. Since the receiver circuit is controlled by turning on the power supply for a specific time, there is an effect that the power consumption of the audio amplifier can be saved.

According to the fifth aspect of the present invention, when the signal from the electric field strength detecting section has a signal and the signal from the voice detecting section has no signal, the timer section is provided in the audio amplifier of the receiver. The power source is turned on for a specific time, the audio amplifier is turned off after the specific time is over, and when the signal from the voice detection section has a signal present state, the timer section turns on the audio amplifier of the receiver. Since the method of controlling the receiver circuit described in 1 is used, there is an effect that the power consumption of the audio amplifier can be saved and the audio amplifier can be operated with priority over the call state.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a receiver circuit according to an embodiment of the present invention.

FIG. 2 is a timing chart showing a correspondence relationship between an output signal from the electric field strength detection unit 10, an output signal from the voice detection unit 11 and a power ON / OFF signal to the audio amplifier unit 6 of the present embodiment.

FIG. 3 is a configuration block diagram of a conventional receiver circuit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High frequency amplification part, 2 ... Intermediate frequency amplification part, 3 ... Demodulation part, 4 ... Noise squelch part, 5 ... Switch part, 6
... audio amplifier section, 7 ... antenna, 8 ... speaker, 10 ... electric field strength detection section, 11 ... voice detection section,
12 ... Timer section

Claims (5)

[Claims] 1. An electric field strength detecting section for detecting electric field strength of a received signal, a voice detecting section for detecting a voice obtained by demodulating the received signal, a signal from the electric field strength detecting section and the voice detecting section. A receiver circuit having a timer unit for controlling on / off of a power supply of an audio amplifier of a receiver by a signal from the receiver circuit. 2. The timer unit turns on the power supply of the audio amplifier of the receiver when the signal from the electric field strength detection unit has a signal present state and the signal from the voice detection unit has a signal present state. A method for controlling a receiver circuit according to claim 1, wherein the method is for controlling a receiver circuit. 3. The timer unit turns on the power supply of the audio amplifier of the receiver for a specific time when the signal from the electric field strength detection unit is in a signal present state and the signal from the voice detection unit is in a no signal state. The method for controlling a receiver circuit according to claim 1, wherein: 4. The timer unit turns on the power supply of the audio amplifier of the receiver for a specific time when the signal from the electric field strength detector has a signal and the signal from the voice detector has no signal. The method of controlling a receiver circuit according to claim 1, wherein: 5. The timer section turns on the power supply of the audio amplifier of the receiver for a specific time when the signal from the electric field strength detection section has a signal and the signal from the voice detection section has no signal. The power supply of the audio amplifier is turned off after the end of the specific time, and the timer unit turns on the power supply of the audio amplifier of the receiver when the signal from the voice detection unit has a signal present state. The method of controlling the receiver circuit according to claim 1.