JPH0479430A - Portable telephone system - Google Patents

Abstract

PURPOSE:To reduce the current consumption in the waiting state of a slave machine having a portable battery as the power source part by including an interrupted monitor circuit and a power switch part provided with a tuning circuit and a contactless switch. CONSTITUTION:An interrupted monitor circuit 54 which is fed by a power source part 50 and interruptedly supplies flash power to a reception part 38 and the power switch part are included, and this power switch part is provided with the tuning circuit which detects the flash reception signal of the reception part 38 and the contactless switch which is turned on by the detection signal of the tuning circuit and continuously supplies the power of the power source part to each part of the slave machine. As the result, the supply voltage is supplied to only the interrupted monitor circuit 54 practically in the state waiting for reception. Thus, the current consumption in the state waiting for reception is reduced.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an improvement in a power supply circuit for reducing current consumption in a standby state in a mobile phone system, particularly in a handset using a portable battery as a power source. Regarding.

[Prior Art] Telephone devices that perform voice or data communication using telephone lines are used in a wide range of industrial fields, and in addition to conventional simple voice communication, u! j 1m or pigs are processed,
For such processing, communication systems using analog, digital, or satellite communication have been put into practical use.

In such a system, in addition to a voice transmitting/receiving device, various data processing terminals such as a facsimile, a computer, or a printer are connected to the telephone terminal.

In a normal telephone system, terminals are directly connected to telephone line terminals, but cordless telephone equipment has been put into practical use to make terminals portable, and they can be used as portable terminals or car telephone terminals. Its popularity is remarkable.

In such a mobile phone system, a carrier signal modulated on a high-frequency carrier is transmitted between a base unit connected to a telephone line and a slave unit carried by the user, and in such wireless communication. Reliable communication control is performed between the base unit and the slave unit using the specified frequency carrier.

FIG. 5 schematically shows a conventional general mobile telephone system, for example, a base unit and a slave unit of a cordless telephone device.

The base unit 10 has a control unit 12 that centrally controls communication signals, is directly connected to a telephone line 14, and transmits and receives necessary voice or data.

In order to transmit and receive such data to and from the handset, the base unit 10 has an antenna 16 and transmits a carrier signal to the antenna 16.
It has an internal transmitter 18 for transmitting data, and on the other hand,
A receiving section 20 is provided to receive the carrier signal from the handset received by the antenna 16, and this received signal is taken into the control section 12 via the demodulating section 22.

The main device 10 also includes a tuning oscillation section 24 for generating high-frequency carrier signals necessary for the transmitting section 18 and the receiving section 20.

Power is supplied to each of these parts from a power supply unit 26 that normally uses a commercial power supply.

On the other hand, the handset 30 has a control unit 32, an antenna 3,
4. It has a transmitter 36, a receiver 38, a demodulator 40, and a tuning oscillator 42, and transmits and receives high-frequency carrier signals in the same way as the base unit. Further, the handset 30 has a necessary output device depending on its usage form, and in FIG.
4. It includes a keyboard input device 46 and a speaker 48, which can control the necessary voice or data output.

Such a handset 30 is provided with a power supply unit 50 consisting of a battery, and normally the handset 30 is always powered by a rechargeable secondary battery.
is held in a reception standby state.

[Problems to be Solved by the Invention] In such a mobile phone system, it is desired that the power supply section of the handset is as small and lightweight as possible, and thereby the scope of use of the handset can be significantly expanded.

However, in the past, the slave unit must always be kept in a state where it can receive carrier signals from the base unit.
Therefore, in normal cases, a predetermined voltage is supplied from the power supply unit to the entire slave device.

For this reason, with conventional handsets, the current consumption in the standby state has reached a point where it cannot be ignored, and even when no actual transmission or reception is taking place, the continuous use time of the handset is limited to less than a few tens of hours. There is an inconvenience that the power supply section must be charged every relatively short period of time.

For this reason, in practice, batteries with relatively large capacities are used in slave units, which is a major factor that hinders miniaturization and weight reduction of slave units, and even if batteries are available for practical use, at least The drawback was that it required charging once every few days.

The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to focus on the fact that the current consumption of conventional handsets occupies a relatively large proportion in the standby state, and to reduce the amount of received carrier signal in the standby state. It is an object of the present invention to provide an improved power supply circuit for a slave device that can completely monitor the data and significantly reduce current consumption in a reception standby state.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a receiving unit that receives a carrier signal from a base unit, a transmitting unit that transmits a carrier signal to the base unit, and a transmitting/receiving signal. An intermittent monitoring circuit that is supplied with power from the power supply unit and intermittently supplies flash power to the reception unit, and a reception unit a power switch unit having a tuning circuit that detects a flash reception signal of the tuning circuit; and a non-contact switch that is turned on by the detection signal of the tuning circuit and continuously supplies power from the power supply unit to each part of the slave device. As a result, the power supply voltage is substantially supplied only to the intermittent monitoring circuit in the reception standby state.

[Operations] Therefore, according to the present invention, in the normal standby state, only the intermittent monitoring circuit consumes current, and the power supply to the other parts of the handset is completely cut off by the power switch section. A significant power saving effect can be obtained.

Furthermore, the power saving effect of the intermittent monitoring circuit that is constantly supplied with power can be sufficiently increased by significantly reducing the duty ratio of the intermittent monitoring during the period in which current is actually consumed.

Normally, in a telephone system, a ring tone is emitted at the time of reception, and this ring tone is captured after the handset starts receiving, and the flash power supply of the intermittent monitoring circuit can reliably capture the ring tone. As a result, the cordless handset of the present invention was able to significantly reduce current consumption in the standby state.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a preferred embodiment of the handset according to the present invention.

In FIG. 1, parts that are the same as or correspond to those of the conventional handset shown in FIG. 5 are given the same reference numerals, and their explanations will be omitted.

In this embodiment, the current consumption of the power source 50 is extremely low, as will be clear from the description below, so a battery with a smaller capacity than conventional batteries can be used, for example, AA batteries. This significantly improves the overall size and weight of the device.

However, in the embodiment, when using, for example, two AA batteries, the voltage cannot be 3VL, and in reality, the transmission system of the slave device commonly used in the past requires 9V. In the case, the R pressure circuit 52
is used, and the necessary 9■ is obtained in the transmitter 36.

A feature of the present invention is that power from the power supply section 50 is always supplied only to the intermittent monitoring circuit 54, and is supplied to all other sections via the power switch section 56.

The intermittent monitoring circuit 54 intermittently supplies flash power to the receiving section 38, and the receiving section 38 captures the carrier signal received from the antenna 34 when the flash power is supplied.

When the receiving section 38 captures this carrier signal, it supplies a minute flash reception signal to the power switch section 56, and the power switch section 56 detects this flash reception signal and recognizes the carrier signal from the base unit. In this state, power from the power supply section 50 is continuously supplied to each section.

When the series of telephone communications is completed, the power switch unit 56 closes its built-in non-contact switch again and returns to the reception standby state.

FIG. 2 shows the intermittent monitoring function of the present invention.

FIG. 2B shows the right-call signal when receiving a telephone call. As shown in the figure, the ringing tone signal sent to the base unit consists of a repeating signal that rings for 2 seconds and pauses for 1 second. Usually, this ringing tone is notified to the user by the sound of a bell, or the ringing tone is detected electrically in the data terminal.

In either state, the terminal and telephone line are connected off-hook, and subsequent signal transmission operations begin.

To explain in more detail, the ringing tone shown in FIG. As shown at A, it is modulated at a carrier frequency of 800 MHz.

As described above, in a normal telephone system, a ringing tone is always sent at the beginning of signal transmission, and the present invention is characterized by intermittent monitoring of this ringing meter.

FIG. 2C shows a flash power supply sent from the intermittent monitoring circuit 54 to the receiving section 38, and as shown in the figure (in the embodiment, a 2rn second flash power supply is used at 1 second intervals).

Therefore, as is clear from FIGS. 2B and C, at least two flash power supplies are inserted for each cycle of the ringing signal, and the seven tones of the call are always monitored twice in each cycle. Become.

Therefore, according to the present invention, it is possible to reliably capture the ringing tone and thereafter start continuously supplying power from the power switch unit 56 to each part of the handset.

In normal cases, the ring tone is repeated multiple times, so even if the carrier signal cannot be captured for some reason in the first ring cycle, it is possible to reliably capture the carrier signal in several subsequent rings. Become.

The second drawing, H, shows an enlarged view of the ringing signal and the flash power supply, and as is clear from the second drawing, the ringing tone of 400 Hz has a period of 2.5 msec. As shown in FIG. 2E, the flash power supply of the embodiment has a duration of 2 milliseconds at intervals of 2 seconds, which indicates that even though the call signal and the flash power supply are asynchronous, the flash power supply is reliable. It becomes possible to capture the call signal using the flash power supply.

Based on the above principle, an embodiment of the present invention is shown in FIG. 3 as a main part thereof.

In FIG. 3, the receiving circuit 38 includes a high frequency amplifier 60 for high frequency amplifying the received signal from the antenna 34, a mixer 62 for mixing the local oscillation signal obtained from the above-mentioned tuning oscillation section 42, and an intermediate frequency amplifier 64. The output is supplied to the demodulator 40 from the terminal 38a.

The characteristic feature of this embodiment is that power is continuously supplied to each circuit 60, 62, 64 of the receiving section 38 from the terminal 38b, and this power is supplied from the output of the power switch section 56 mentioned above. This is obtained from the terminal 56a.

Therefore, when the power switch section 56 is off, the receiving section 38
Power supply to all circuits has been cut off.

Furthermore, a feature of this embodiment is that the high frequency amplifier 60 of the receiving section 38 is supplied with flash power from the terminal 38c in addition to the power supply from the power switch section 56.

As is clear from the above description, this flash power is supplied from the output terminal 54a of the intermittent monitoring circuit 54.

Therefore, it is understood that according to this embodiment, only the high frequency amplifier 60 is intermittently activated by the flash power supply.

The output of the high frequency amplifier 60 in this embodiment is outputted to a mixer 66 in the same way as a normal receiving section, and, as is characteristic in this embodiment, from the terminal 38d to the input terminal of the power switch section 56 described above. 56b, this flash reception signal is captured by the power switch unit 56, and turns on a power switch, which will be described later.

Next, the intermittent monitoring circuit 54 that forms the flash power supplied to the input end 38c of the receiving section 38 will be explained.

The intermittent monitoring circuit 54 in the embodiment includes a transistor Tl,
T2. T3. T4, and the power supply VB from the power supply section 50 is supplied to the input terminal 54b.

Further, the terminal 54c is grounded, and a charging/discharging capacitor C, which is characteristic in this embodiment, is connected between the terminal 54d and the output end 54a, and further between the terminal 54e and the output end 54a. Diode D is connected.

In the embodiment, the capacitor C is an external component, which allows its charging and discharging time to vary by M.

In this embodiment, as shown in FIG. 2 C or E, the charging and discharging period of the capacitor C is set to 1 second, and by setting the discharging period to 2 msec, a flash with a duty ratio of 2/1000 is used. Power can be supplied to the receiving section 38.

Therefore, the current consumption in the high frequency amplifier 60 of the power supply section 38 is also an extremely short operation, and a significant power saving effect can be achieved.

Next, the power switch section 56 in this embodiment will be explained.

The power switch section 56 is a non-contact switch 7 consisting of an FET.
0, the power supply VB is supplied to the input terminal 56c, and the power supply VB is output from the output terminal 56a to the terminal 72 only when the non-contact switch 70 is turned on.
In the figure, power is continuously supplied to the input terminal 38b of the receiving section 38, and power is supplied from the terminal 72 to each part of the slave unit.

Therefore, in this embodiment, when the non-contact switch 70 is turned off, the power supply is cut off to almost all the circuit parts of the handset, and the current consumption of the handset in the receiving standby state can be significantly reduced. be.

In order to turn on the non-contact switch 70, the power switch section 56 is provided with a tuning circuit that uses the flash signal output from the reception section 38, and this tuning circuit has a piezo effect in the embodiment. The flash detection signal supplied from the output end 38d of the receiving circuit 38 to the input end 56b of the power switch section 56 is supplied to the piezoelectric element 74.

The pressure element 74 mechanically oscillates synchronously with the flash reception signal, and the voltage generated by this oscillation is applied to the multistage amplifiers AI, A2 . A3. The signal is amplified at A4 and supplied to the gate power of the non-contact switch 70.

The piezoelectric element 74 used in the example is made of a ceramic piezoelectric element, one electrode of which is grounded, and the flash detection signal is supplied to the other electrode to cause the ceramic piezoelectric element to resonate, As a result, a piezoelectric signal is applied to each of the multi-stage connected amplifiers A1 to A4 from an output electrode further laminated on the input electrode due to the mechanical vibrations generated.

In the embodiment, the piezo voltage of about 10 mV is obtained, which is boosted 15 by multistage amplification, and as a result, a gate signal of about 2 V can be supplied to the gate input of the non-contact switch 70.

In the embodiment, the non-contact switch 70 is composed of an FET,
Since the FET is a voltage-driven element, the FET can be easily turned on by a gate input of, for example, 07V or more.

Therefore, according to the present invention, it is possible to supply power to each section by turning on the power contact of the electric δJK switch section 56 only when the receiving section 38 captures a telephone ringing tone.

As mentioned above, the receiving section 38 also receives the output from the power switch section 56, and its high frequency amplifier 60 and mixer 62
Since the intermediate frequency amplifier 64 and the intermediate frequency amplifier 64 are all supplied with power, they can carry out normal reception operations, and at this time, a desired reception signal can be supplied to the demodulation section 40, which is already supplied with power.

At this time, the receiving section 38 receives a continuous power supply from the power switch section 56 and also receives a parallel supply of flash power from the intermittent monitoring circuit 54, but such parallel power supply does not cause any circuit operation. It will not cause any hindrance.

When the receiving unit 38 continues receiving signals from the base unit, the output of the high frequency amplifier 60 is always output from the terminals 38d and 5.
Since the flash detection signal continues to be supplied from 6b to the tuning circuit of the power switch unit 56, as a result, the non-contact switch 70 can continue to be in its on state and can continue to supply power to the terminal 72.

When all calls are completed, the flash detection signal of the receiving section 38 disappears, and as a result, the tuning circuit of the power switch section 56 becomes inactive, so the non-contact switch 70 consisting of an FET is also turned off. Power supply to each part can be cut off.

As described above, according to the present embodiment, only the intermittent monitoring circuit 54 consumes current in the reception standby state, and this current consumption is also significantly reduced because the duty ratio is 2/1000. be able to.

In addition, since the non-contact switch 70 of the power switch section 56 also uses a voltage-driven FET, its off operation "[-
1 has the advantage of not requiring current consumption.

FIG. 4 shows a specific circuit configuration of the booster circuit 52 used in this embodiment, and the booster circuit 52 includes transistors T5. The transistor T5 performs an oscillation operation at a predetermined frequency, and for example, in the embodiment, the transistor T5
Oscillation of approximately kHz is occurring.

Then, the AC signal obtained in this way is charged and integrated for each half wave by the capacitor CI C2 and the diodes DI and D2D3, and is thereby multiplied by 3, and the 3V power supply voltage obtained from the input terminal 52a is can be multiplied to a power supply voltage of 9 cm at the output terminal 521 and supplied to the transmitter 36.\\.

Note that the Zener diode ZD forms a reference constant voltage for the output 9.

Therefore, according to this embodiment, a 3V power supply made by connecting two AA batteries in series as the power supply unit 50 can sufficiently supply the necessary current to each part, and the 9V power supply required for the transmitter etc. is provided by the booster circuit 52. taken from.

[Effects of the Invention] As explained above, according to the present invention, it is possible to reliably capture the transmission signal from the base unit, and the current consumption in the receiving standby state is significantly reduced, thereby significantly reducing the current consumption of the slave unit. It can save electricity.

Therefore, according to the present invention, the battery of the handset is made smaller and lighter,
The portability of the handset is significantly improved, and the required charging cycle or time for replacing electricity can be extended.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of a preferred embodiment to which a cordless telephone handset according to the present invention is applied, FIG. 2 is an explanatory diagram showing the principle of the present invention, and FIG. FIG. 4 is a circuit diagram showing a specific circuit configuration of the booster circuit in this embodiment. FIG. 5 is a schematic explanatory diagram of a conventional cordless telephone device. 38 ... Receiving section 50 ... Power supply section 54 ... Intermittent monitoring circuit 56 ... Power switch section

Claims (1)

[Scope of Claims] A receiving unit that receives a carrier signal from the base unit, a transmitting unit that transmits the carrier signal to the base unit, a control device within the slave unit that processes the transmitted and received signals, and supplies power to each of the units. A mobile phone system comprising: a power supply unit that receives power from the power supply unit; an intermittent monitoring circuit that is supplied with power from the power supply unit and intermittently supplies flash power to the reception unit; a tuning circuit that detects a flash reception signal of the reception unit; A mobile phone system comprising: a power switch section having a non-contact switch that is turned on by a detection signal and continuously supplies power from a power supply section to various parts of the handset.