JPH0453076Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a wireless device suitably implemented in, for example, a car telephone.

BACKGROUND TECHNOLOGY For example, a car phone communicates with a telephone connected by wire to the telephone network by radio communication with a base station installed in various places and connected to the telephone network.

The radio waves generated by the car and the radio waves generated by the base station for performing the wireless communication have a limit in their electric field strength, so if the car is far away from the base station, it becomes impossible to perform the wireless communication.

A communicable area where the electric field strength generated by the base station is sufficiently strong and wireless communication is effective is as shown in FIG. 4, for example. FIG. 4 is a diagram schematically showing a communication situation between a car telephone (not shown) mounted on the car 1 and the telephone 2 connected to a telephone line network. The base station 3 is connected to the telephone line network,
Radio communication is performed with a car telephone in the car 1 via the antenna 4. A communicable area 5 in which the electric field strength of the base station 3 is sufficiently strong so that wireless communication with a car telephone is possible is indicated by a phantom line.

When the car phone is located within the communicable area 5, wireless communication between the car phone and the base station 3 via the antenna 4 is possible, and therefore communication with the phone 2 is possible. When the vehicle 1 is located outside the communicable area 5, the field strengths of both the radio waves generated from the antenna 4 and the radio waves generated from the vehicle 1 are not sufficient, so in this case, the vehicle Communication between the telephone set and the telephone set 2 cannot be performed.

When the car 1 is located outside the communicable area 5, it is impossible to communicate with the car phone installed in the car 1, so a message indicating that the car 1 is located outside the communicable area 5 is displayed. Car telephones have been used for some time.

Problems to be solved by the invention Even when the car 1 is located outside the communication area 5, the car phone installed in the car 1 is powered with electricity as in the normal case, so there is no waste. consumes electricity. That is,
For example, the operating section of a car telephone, including dial buttons, is equipped with a lamp associated with each keytop, and this lamp is energized when the power is turned on, so that it can be used at night without turning on the interior lights of the car. , the operating section is configured to be operable. The above-mentioned lamp is lit even outside the communicable area 5, which is extremely wasteful.

An object of the present invention is to provide a wireless device whose power consumption is reduced outside the communicable area, and which can therefore reduce overall power consumption.

Means for Solving the Problems The present invention provides a wireless device that is equipped with an operation unit to which driving power is supplied and in which a communicable area is set. This wireless device is characterized by comprising an out-of-area detection means for outputting an output, and a power suppression means for reducing a power level for energizing an operation unit in response to the output of the out-of-area detection means.

Function In the present invention, the out-of-area detection means outputs an out-of-area detection signal when the wireless device is outside the communicable area. The power suppressing means reduces the power level for energizing the operating section in response to the output of the out-of-area detection means. As a result, the power consumption of the wireless device outside the communicable area is reduced, and therefore the overall power consumption of the wireless device is significantly reduced.

Embodiment FIG. 1 is a block diagram showing the basic configuration of a car telephone (hereinafter referred to as a telephone) 11 which is an embodiment of the wireless device of the present invention. The telephone 11 communicates with a base station (not shown) through an antenna 13 connected to a high frequency amplifier 16. The high frequency amplifier 16 is the antenna 13
extracting a signal in a unique frequency band assigned to the telephone 11 from among the signals received by the telephone 11, and exchanging the signal with a signal in an intermediate frequency band by a mixer (not shown); It is applied to the intermediate frequency amplifier 12.

The intermediate frequency amplifier 12 amplifies the signal in the intermediate frequency band and supplies it to the detection circuit 14 and the detection circuit 15. Detection circuit 14 demodulates the output of intermediate frequency amplifier 12 into an audio signal, and the demodulated audio signal is provided to handset 18 via interface 17. In FIG. 1, parts related to transmission are omitted.

The signal applied from the intermediate frequency amplifier 12 to the detection circuit 15 is subjected to, for example, average value detection in the detection circuit 15, and the average value level is applied to the comparator 19. The comparator 19 compares the reference voltage provided by a configuration not shown and the voltage level provided from the detection circuit 15, and
A high level or low level signal is given to the processing unit (Processing Unit) 20. The output of the CPU 20 is provided to the handset 18 as an out-of-area detection signal. This out-of-area detection signal has a frequency of 1, for example.
It may be a Hz pulse signal. The comparator 19 is
For example, when the level of the signal provided from the detection circuit 15 is less than the reference voltage, a low level signal is output, and at this time the CPU 20 outputs the above-mentioned out-of-area signal.

The detection circuit 15, the comparator 19 and the CPU 2
The out-of-area detection means includes 0. Also, a high frequency amplifier 16, an intermediate frequency amplifier 12, detection circuits 14, 15, an interface 17, a comparator 19,
The CPU 20 and the like are housed in the main body 10 of the telephone 11.

The interface 17 is connected to a handset 21 in the handset 18, and the operator can
Make calls via . The output of the CPU 20 is sent to the CPU 2 through a buffer 22 in the handset 18.
given to 3. The CPU 23 provides a signal to change the display state of the display section 25, which is realized by a liquid crystal display device, etc., via a line 24, as will be described later.
A high level or low level signal is applied to the base of the NPN type transistor Tr1 via the transistor Tr1.
The emitter of the transistor Tr1 is grounded, and its collector is connected to the light emitting diode D1. In addition, the CPU 23 is connected to the line 27 and the resistor R
A high level/low level signal is applied to the base of the NPN type transistor Tr2 through the transistor Tr2. The emitter of the transistor Tr2 is grounded,
Further, its collector is connected to a plurality of light emitting diodes D connected in parallel. The light emitting diode D
is arranged in association with a dial button, etc., which will be described later. The CPU 23 and the transistor Tr1,
Power suppressing means is configured including Tr2.

The terminal of the light emitting diode D1 opposite to the transistor Tr1 is connected to the power supply voltage via the resistor R2.
Vcc is given. When the CPU 23 derives a high level signal on the line 26, the transistor
Tr1 becomes conductive, thereby causing the light emitting diode D
1 is conductive. When the CPU 23 outputs a low level signal on the line 26, the transistor Tr1 is cut off, and thereby the light emitting diode D1 is also cut off.

The light emitting diode D1 is used as a lamp to indicate that the car in which the telephone 11 is mounted is located outside the communicable area. Therefore
When the CPU 23 receives an out-of-area detection signal from the CPU 20 via the buffer 22, it outputs a high-level signal to the line 26, and when the out-of-area signal is not applied, it outputs a low-level signal. As a result, the light emitting diode D1 enters a light emitting state when the car in which the telephone 11 is mounted is outside the communicable area.

In addition, the power supply voltage is connected to the terminal of the light emitting diode D on the opposite side of the transistor Tr2 through a resistor R4.
Vcc is given. The CPU 23 outputs a low level signal to the line 27 when the out-of-area signal is applied, and outputs a high-level signal to the line 27 when the out-of-area signal is not applied. This causes the light emitting diode D to emit light only within the communicable area.

FIG. 2 is a plan view showing a simplified configuration of the handset 18. The front face of the handset 18 is provided with a plurality of dial buttons 30 for inputting a calling number, and a display section 25 realized by a liquid crystal display or the like.
Further, a function button 31 is provided which is used to change the display contents on the display section 25 or to store a specific call number. Call button 30
and the display unit 25, there is a power display lamp 32 that indicates that the telephone 11 including the handset 18 is powered on, and a switch (not shown) that is shut off by the operator. A lamp 33 is provided to indicate that it is possible to make a call using the handset 18, and the above-mentioned light emitting diode D1, which lights up outside the communicable area, is also provided.

When the operator presses the function button 31a among the function buttons 31 for instructing to shut off the switch, the lamp 33 lights up and the telephone becomes ready for communication. After this, when the dial button 30 is operated to input a calling number and the telephone of the communication destination corresponding to the inputted calling number is connected to the telephone line, a call can be made using the transmitting part 34 and the receiving part 35. become. A volume control switch 36 is disposed on the side of the handset 18 to adjust the volume of the voice that is converted into sound by the receiver 35. Such a handset 18 is connected to the main body 10 via a cord 37.

A light emitting diode D shown in FIG.
The display on each key top of the function button 31 can be checked even at night without turning on the interior lights of the car.

The light-emitting diode D is not energized when the car in which the telephone 11 is installed is located outside the communication area and the light-emitting diode D1 is in the light emitting state, thereby preventing the light emitting diode D from being energized when the car in which the telephone 11 is installed is located outside the communication area. Pointless power consumption is prevented. Similarly, when the light emitting diode D1 is turned on, the display section 25 is also
CPU 23 is controlled from being powered by a signal derived on line 24. The operation section includes the display section 25, the dial button 30, the function button 31, the light emitting diode D, and the like. Further, the transmitter/receiver section 21 includes a transmitter section 34 and a receiver section 35 .

FIG. 3 is a flowchart for explaining the operation of the telephone 11. First, when the power of the telephone 11 is turned on in step n1, the step
At n2, the telephone 11 transmits an identification signal from the antenna 13 to the base station indicating that the telephone 11 is ready to make/receive calls. When the base station receives this identification signal, the telephone 11 is ready for use.

Thereafter, in step n3, the CPU 20 refers to whether the signal provided from the comparator 19 is at a high level or a low level and determines whether the car in which the telephone set 11 is mounted is within the communicable area.
If it is determined in step n3 that the device is within the communicable area, the process proceeds to step n4, where the operator presses dial button 30 and function button 3.
1 is operated, a call is made to a telephone set connected to the telephone line network. After this, when the destination phone is connected to the telephone line network, phone 1
It becomes possible to make a call between 1 and the destination telephone.

When it is determined in step n3 that the area is outside the communicable area, in step n5,
The CPU 20 sends out-of-area signals via the buffer 22.
The light emitting diode D1 is turned on, the light emitting diode D is cut off, and the display section 25 is put into a non-display state. After this, the process returns to step n3.

As described above, in this embodiment, the comparator 19 detects whether the electric field strength of the radio waves generated by the base station is above a certain level. A high level signal is given to the CPU 20, and a low level signal is given to the CPU 20 when the level is below a certain certain level.

When the CPU 20 receives a high-level signal from the comparator 19, it determines that it is within the communicable area, and when it receives a low-level signal, it determines that it is outside the communicable area.
When the CPU 20 determines that the area is outside the communicable area, the CPU 20 provides an out-of-area signal realized by, for example, a 1 Hz pulse signal to the CPU 23 via the buffer 22. At this time
The light emitting diode D is activated by the output signal of the CPU23.
1 is conductive, the light emitting diode D is cut off, and the display section 25 is controlled to be in a non-display state.

As a result, when outside the communicable area, only the light emitting diode D1 for indicating that the area is outside the communicable area is energized and becomes a light emitting state, and the light emitting diode D1 that is connected to each key top of the display section 25 and the dial button 30 is activated. Light emitting diode D provided
is not powered. Therefore, unnecessary power consumption outside the communicable area is reduced, and further heat generation by the light emitting diode D is prevented.

In the embodiment described above, only the light emitting diode D1 is conductive outside the communicable area, and the light emitting diode D is cut off.
This may be achieved by, for example, reducing the amount of light emitted by the light emitting diode D by reducing the current flowing through the light emitting diode D outside the communicable area. Thereby, since the brightness of the light emitting diode D differs between inside and outside the communicable area, it can be confirmed whether the car in which the telephone 11 is mounted is located within the communicable area.

Further, in the above embodiment, the handset 18
is connected to the main body 10 via the cord 37, but the present invention connects the handset 18 and the main body 10.
It can also be easily applied to a telephone with an integrated structure. Furthermore, the present invention is widely applicable to wireless devices other than telephones, in which a communication area is set.

Effects As described above, according to the present invention, power consumption outside the communicable area is reduced, and overall power consumption can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of a telephone set 11 which is an embodiment of the present invention, FIG. 2 is a plan view showing a simplified configuration of a handset 18, and FIG.
The figure is a flowchart for explaining the operation of the telephone 11, and FIG. 4 is a diagram for explaining the communicable area. 11... Car telephone, 14, 15... Detection circuit, 18... Handset, 19... Comparator,
20, 23...CPU, 25...Display section, 30...
...Dial button, 31...Function button, D, D
1...Light emitting diode, Tr1, Tr2...Transistor.

Claims (1)

[Claims for Utility Model Registration] In a wireless device equipped with an operation unit to which driving power is supplied and in which a communicable area is set, an out-of-area signal that detects that it is outside the communicable area and outputs an out-of-area signal. 1. A wireless device comprising: a detection means; and a power suppression means for reducing a power level for energizing an operating unit in response to an output of the out-of-area detection means.