JPH0993190A - Radio communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication equipment with a radio wave environment immune from noise into speech voice signal. SOLUTION: A control circuit 215 for a master set 42a in communication with a slave set 42b decides whether or not a measurement value of a reception electric field strength received at 1sec period keeps a reference level 1 or over for 5 seconds and decides whether or not a measurement value of a reception electric field strength received at 1sec period keeps a reference level 2 or less. When the measurement value of the reception electric field strength is less than the reference level 2 even once and the radio wave transmission power is set to a weak level, it is judged that there is a hindrance in communication by the weak radio wave transmission power and the control circuit 15 gives a command of the strong radio transmission power to a radio wave transmission power changeover circuit of a tuner 12 and the slave set 42b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication device having a master unit and a slave unit that wirelessly communicates with the master unit.

[0002]

2. Description of the Related Art Conventionally, a so-called cordless telephone apparatus having a base unit and a handset that wirelessly communicates with the base unit, a so-called cordless telephone device, enables a call at a predetermined level between the base unit and the handset. , A radio wave transmission power switching means for selectively switching the intensity of radio wave transmission power in the master unit and the slave unit between strong and weak levels, and measures the received electric field strength in the master unit.
The switching operation of the radio wave transmission power switching means of the master unit and the slave unit is controlled according to the measured received electric field strength. A control unit for the switching operation of the radio wave transmission power switching unit of the master unit and the slave unit is provided in the master unit, and this control unit controls the switching operation of the radio wave transmission power switching unit of the master unit and transmits the radio wave to the slave unit. A wireless control signal for controlling the switching operation of the power switching means is transmitted. The radio wave transmission power switching means of the slave unit switches to the radio wave transmission power of a corresponding magnitude based on the radio control signal transmitted from the master unit.

A control method for the switching operation of the radio wave transmission power switching means of the master unit and the slave unit will be described in detail with reference to FIG. FIG. 8 is a flow chart showing the control for the switching operation of the radio wave transmission power switching means, which is executed by the master unit of the conventional cordless telephone system.

Referring to FIG. 8, first, in a call state between the base unit and the handset, the received electric field strength at the base unit is measured every one second (step S801), and the measured value of the received electric field strength is analog. Converted to digital data by digital conversion (hereinafter referred to as AD conversion) (step S
802).

Then, it is judged at what level the measured value of the received electric field strength converted into digital data is maintained for 5 seconds (steps S803 and S807). Specifically, it is determined whether or not the measured value of the received electric field strength is a value equal to or higher than the reference level 1 for 5 seconds (step S803).
And the measured value of the received electric field strength is 5 below the reference level 2.
It is determined whether or not it has been maintained for a second (step S807). The reference level 1 and the reference level 2 are
It is a reference value for determining whether or not the measured received electric field strength has sufficient strength for a call. If the received electric field strength is a value of reference level 1 or more, the received electric field strength is sufficient for a call. If the received electric field strength is a value less than the reference level 2, it is judged that the received electric field strength is weak to a certain extent.

If the measured value of the received electric field strength converted into digital data continues to be the reference level 1 or more for 5 seconds (step S803), it is determined whether or not the current radio wave transmission power is set to be strong. It is determined whether (step S804). If the magnitude of the radio wave transmission power is not set to high, it is determined that the currently set magnitude (that is, weak) of the radio wave transmission power is sufficient to obtain a reception electric field strength that enables communication, and the process is performed again. It returns to S801. On the other hand, if the magnitude of the radio wave transmission power is set to a strong level, the strength of the radio wave transmission power is set to a sufficient level to obtain a reception electric field strength that enables sufficient communication. It is determined that the radio wave transmission power can be weakly switched, and a control signal for instructing the radio wave transmission power switching means of the master unit to switch the radio wave transmission power to weak is output (step S805). The radio signal transmission power of the parent device is switched to weak by this control signal.

Next, a radio wave transmission power instruction for instructing the slave unit to weakly switch its radio wave transmission power is transmitted by a radio control signal (step S806), and the radio wave transmission power switching of the slave unit receiving the radio control signal is switched. The means switches the magnitude of the radio wave transmission power to weak if the current radio wave transmission power is strong.

If the measured value of the received electric field strength converted into digital data remains below the reference level 2 for 5 seconds (step S807), it is determined whether or not the current magnitude of the electric wave transmission power is set to be weak. It is determined whether (step S808). If the magnitude of the radio wave transmission power is not set to be weak, that is, if the magnitude of the radio wave transmission power is currently set to be strong, the magnitude of the radio wave transmission power cannot be further increased. Therefore, the process is performed again in step S801. Return to. On the other hand, if the magnitude of the radio wave transmission power is set to weak, it is determined that a weak radio wave transmission power will interfere with the call, and the radio wave transmission power switching means of the master unit will be set to transmit the radio wave transmission power. A control signal for instructing to make it strong is issued (step S809). This control signal causes the radio wave transmission power of the base unit to be strongly switched.

Next, a radio control signal indicating a radio wave transmission power instruction for instructing the slave unit to increase its radio wave transmission power is transmitted (step S806), and the radio wave transmission power of the slave unit receiving the radio control signal is transmitted. If the current radio wave transmission power is weak, the switching means switches the magnitude of the radio wave transmission power to strong.

As described above, when the measured value of the received electric field strength remains at the reference level 1 or more for 5 seconds, that is, when the state of the received electric field strength is strong for a predetermined time, the electric wave transmission power is switched from strong to weak. If the measured value of the received electric field strength is less than the reference level 2 for 5 seconds, that is, if the received electric field strength is weak for a predetermined time, the electric wave transmission power is switched from weak to strong.

[0011]

However, in the conventional cordless telephone device, the strength of the electric wave transmitted cannot be switched to a strong level unless the weak electric field strength is maintained for a predetermined time. In a radio wave environment in which the state occurs intermittently, the magnitude of the radio wave transmission power is kept weak, and noise is likely to be introduced into the call voice. As a result, there is a risk that noise may prevent smooth communication.

An object of the present invention is to provide a wireless communication device capable of obtaining a radio wave environment in which noise is unlikely to enter during a voice call.

[0013]

According to the first aspect of the present invention,
Received electric field strength measuring means for measuring the received electric field strength in at least one of the master unit and the slave unit that wirelessly communicates with the master unit, and radio wave transmission in the master unit and the slave unit according to the measured received field strength In a wireless communication device comprising radio wave transmission power switching means for selectively switching the magnitude of electric power, a judgment range for the measured received electric field strength requesting a switching operation of the radio wave transmission power from small to large is the radio wave transmission. The radio wave transmission power switching determination is performed based on a determination condition that is set wider than the determination range for the measured received electric field strength that requires a switching operation from high power to low power.

According to a second aspect of the present invention, in the radio communication device according to the first aspect, the radio wave transmission power switching determination is such that the measured reception electric field strength is a value equal to or higher than a first determination level for a first determination time. Including a first determination as to whether or not the above persistence and a second determination as to whether or not the measured received electric field strength is a value lower than a second determination level set lower than the first determination level When the measured received electric field strength is equal to or higher than a first judgment level for a first judgment time or longer, the radio wave transmission power is controlled to be switched from high to low, and the measured received electric field strength is controlled. Is lower than the second determination level, the radio wave transmission power is controlled to be switched from small to large.

The third aspect of the present invention provides the first or second aspect.
In the wireless communication device described above, the reception electric field strength measuring means is provided in the master unit, and the master unit performs the radio wave transmission power switching determination and switches the radio wave transmission power corresponding to the radio wave transmission power switching determination result. Is instructed to the slave unit.

The invention according to claim 4 is the invention according to claim 1 or 2.
In the wireless communication device described above, the reception electric field strength measuring means is provided in the slave unit, and the slave unit performs the radio wave transmission power switching determination and switches the radio wave transmission power corresponding to the radio transmission power switching determination result. Is instructed to the parent device.

The invention according to claim 5 is the invention according to claim 1 or 2.
In the wireless communication device as described above, the reception electric field strength measuring means is provided in each of the master unit and the slave unit, and the radio wave transmission power switching determination is performed in each of the master unit and the slave unit. To do.

According to a sixth aspect of the present invention, in the wireless communication apparatus according to the third aspect, a control signal for instructing the slave unit to switch the radio wave transmission power is provided in an area outside a voice band. It is characterized by using a radio signal of a certain frequency.

According to a seventh aspect of the present invention, in the wireless communication apparatus according to the third aspect, a signal of a digital wireless D channel is used as a control signal for instructing the slave unit to switch the radio wave transmission power from the master unit. It is characterized by using.

According to an eighth aspect of the present invention, in the wireless communication apparatus according to the fourth aspect, a control signal for instructing the master unit to switch the radio wave transmission power from the slave unit to an area outside a voice band. It is characterized by using a radio signal of a certain frequency.

According to a ninth aspect of the present invention, in the wireless communication apparatus according to the fourth aspect, a signal of a digital wireless D channel is used as a control signal for instructing the master unit to switch the radio wave transmission power from the slave unit. It is characterized by using.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing a configuration of a telephone exchange device accommodating a first embodiment of a telephone device of the present invention.

As shown in FIG. 1, the telephone exchange apparatus 3 includes a digital interface 7 for connecting a digital communication network (ISDN) 1, an analog interface 8 for connecting an analog communication network (PSTN) 2, and an extension interface 5.
With. A plurality of extension-only telephones 41 and a plurality of analog type extension cordless telephones 42 are connected to the extension interface 5, and each extension cordless telephone 42 is connected.
Is a wireless communication device having a master device 42a and a slave device 42b that performs wireless communication with the master device 42a.

Voice information from the digital interface 7, the analog interface 8 and the extension interface 5 is exchanged in the communication path 6 and the digital interface 7, the analog interface 8, the extension interface 5 and the communication path 6 are controlled. Is performed by the control circuit 9. A program indicating a control procedure executed by the control circuit 9 is stored in the ROM 10 and is used as a work area for arithmetic processing necessary for controlling the control circuit 9 as R
AM11 is used.

Next, the configuration of the extension cordless telephone 42 will be described with reference to FIGS. 2 is a block diagram showing a configuration of a base unit of the extension cordless telephone of FIG. 1, and FIG. 3 is a block diagram showing a configuration of a handset of the extension cordless telephone of FIG.

The master unit 42a has an interface 14 connected to the telephone exchange 3 as shown in FIG.
Voice information is exchanged between the telephone exchange device 3 and the tuner 12 via the interface 14 and the voice processing circuit 13.

The voice processing circuit 13 performs a predetermined process on the voice information. The tuner 12 performs a transmission process for modulating the voice information with a radio wave of a predetermined frequency and then transmitting it from the antenna, and a reception process for demodulating the radio wave from the handset received by the antenna and then transmitting it to the voice processing circuit 13. I do. The tuner 12 has a radio wave transmission power switching circuit (not shown) that selectively switches the radio wave transmission power between two levels, strong and weak.
A measuring circuit (not shown) for measuring the received electric field strength indicating the strength of the radio wave received by the antenna, and a circuit for transmitting a radio control signal for instructing the magnitude of the radio wave transmission power to the slave unit 42b ( (Not shown) and are included. A digital wireless D channel signal is used as the wireless control signal. A radio signal having a frequency outside the voice band may be used instead of the digital radio D channel signal.

Interface 14, voice processing circuit 13,
Control of each of the tuners 12 is executed by the control circuit 15. The control program executed by the control circuit 15 is stored in the ROM 16, and the control information used for the control is E and the ID information of the extension cordless telephone.
It is stored in the EPROM 17. In addition, the control circuit 15
RAM1 is used as a work area for arithmetic processing required to control
8 is used.

The control program stored in the ROM 16 includes a program for controlling the switching operation of the radio wave transmission power by the radio wave transmission power switching circuit of the tuner 12 according to the measured received electric field strength. In the control by, it is judged whether the measured received electric field strength is kept at a value of the reference level 1 or more for a predetermined time (5 seconds) or more, and the measured received electric field strength is set to be lower than the reference level 1. It is determined whether or not the value is lower than level 2, and the control of the switching operation of the radio wave transmission power by the radio wave transmission power switching circuit is performed according to these determination results, and the radio wave is transmitted to the slave unit 42b in accordance with the control execution. A process of transmitting a wireless control signal for instructing the magnitude of output power is executed.

Next, the structure of the slave unit 42b will be described with reference to FIG.

The slave unit 42b, as shown in FIG.
2a has a tuner 19 for performing wireless communication, and the tuner 12 modulates the voice information from the voice processing circuit 20 with a radio wave of a predetermined frequency and then transmits it from the antenna to the master unit 42a. The reception processing for transmitting to the voice processing circuit 20 after demodulating the radio wave from the slave unit received in step S1 is performed. The tuner 12 includes a radio wave transmission power switching circuit (not shown) that selectively switches the radio wave transmission power between two levels, strong and weak.

A receiver 21 and a microphone 22 are connected to the voice processing circuit 20, the voice from the master unit 42a is output from the receiver 21, and the voice on the slave unit 42b side is input to the microphone.

Control of the microphone 22, the receiver 21, the voice processing circuit 20, and the tuner 19 is executed by the control circuit 25. The control circuit 25 performs detection control of the input of the key 26, display control of the LCD 23, and display control of the LED 24 in addition to the control of the tuner 19 described above. The control program executed by the control circuit 25 is R
The control information stored in the OM 27 and used for the control is EEPRO together with the ID information of the extension cordless telephone.
It is stored in M28. Further, the RAM 29 is used as a work area for arithmetic processing necessary for controlling the control circuit 25.

The control program stored in the ROM 27 controls the switching operation of the radio wave transmission power by the radio wave transmission power switching circuit of the tuner 19 based on the radio control signal indicating the radio wave transmission power instruction transmitted from the parent device 42a. A program for is included.

Next, the control for the switching operation of the radio wave transmission power in the extension cordless telephone 42 will be described with reference to FIGS. 4 and 5. FIG. 4 is a flow chart showing control for switching operation of radio wave transmission power in the master unit of the extension cordless telephone of FIG. 2, and FIG. 5 is a flow chart showing control for switching operation of radio wave transmission power in the slave unit of the extension cordless telephone of FIG. is there.

As shown in FIG. 4, the control circuit 15 of the parent device 42a, which is in a call with the child device 42b, receives the received electric field intensity measured by the tuner 12 every one second (step S401), and receives the signal. The measured value of the electric field strength is converted into digital data by AD conversion (step S40).
2).

Next, it is judged which reference level the measured value of the received electric field intensity is (step S403,
S407). Specifically, it is determined whether or not the measured value of the received electric field strength is equal to or higher than the reference level 1 for 5 seconds (step S403), and the measured value of the received electric field strength is less than the reference level 2. Whether or not (step S40
7) and are performed. The reference level 1 and the reference level 2 are reference values for determining whether or not the measured received electric field strength has sufficient strength for a call, and if the received electric field strength is a value equal to or higher than the reference level 1. The received electric field strength is judged to be strong enough to carry out the call, and if the received electric field strength is a value less than the reference level 2, it is judged that the received electric field strength is weak to some extent.

If the measured value of the received electric field strength is above the reference level 1 for 5 seconds, that is, if the value of the received received electric field strength is above the reference level 1 for five consecutive times (step (S403), it is determined whether or not the magnitude of the current radio wave transmission power is set to be strong (step S404). If the magnitude of the radio wave transmission power is not set to high, it is determined that the currently set magnitude (that is, weak) of the radio wave transmission power is sufficient to obtain a reception electric field strength that enables communication, and the process is performed again. Return to S401. On the other hand, if the magnitude of the radio wave transmission power is set to a strong level, the strength of the radio wave transmission power is set to a sufficient level to obtain a reception electric field strength that enables sufficient communication. It is determined that weak switching is possible, and a control signal for instructing the radio wave transmission power switching circuit of the tuner 12 of the parent device 42a to weaken the radio wave transmission power is output (step S405). This control signal causes the radio wave transmission power of the parent device 42a to be weakly switched.

Then, a radio control signal indicating a radio wave transmission power instruction for instructing the slave unit 42b to reduce its radio wave transmission power is transmitted (step S406), and the process returns to step S401 again.

If the measured value of the received electric field intensity is less than the reference level 2, that is, if the received value of the received electric field intensity becomes a value less than the reference level 2 even once (step S4).
07), it is determined whether or not the magnitude of the current radio wave transmission power is set to be weak (step S408). If the magnitude of the radio wave transmission power is not set to be weak, that is, if the magnitude of the radio wave transmission power is currently set to be strong, the magnitude of the radio wave transmission power cannot be further increased, and therefore the process is performed again in step S401. Return to. In contrast,
If the magnitude of the radio wave transmission power is set to weak, it is determined that a weak radio wave transmission power will interfere with the call.
A control signal for instructing the radio wave transmission power switching circuit of the tuner 12 to increase the radio wave transmission power is output (step S409). This control signal causes the radio wave transmission power of the parent device 42a to be strongly switched.

Then, a radio control signal indicating a radio wave transmission power instruction for instructing the slave unit 42b to increase its radio wave transmission power is transmitted (step S406), and the process returns to step S401 again.

On the other hand, as shown in FIG. 5, the control circuit 25 of the slave unit 42b receives the radio control signal from the master unit 42a, that is, the radio wave transmission power instruction (step S5).
01), it is determined whether or not the radio wave transmission power instruction from the parent device 42a indicates the radio wave transmission power strength (step S5).
02).

When the radio wave transmission power instruction from the master unit 42a indicates the high radio wave transmission power, a control signal for instructing the radio wave transmission power switching circuit of the tuner 19 to switch the radio wave transmission power to strong is output. (Step S503),
The radio wave transmission power switching circuit of the tuner 19 switches the magnitude of the radio wave transmission power to strong if the current radio wave transmission power is weak.

When the radio wave transmission power instruction from the parent device 42a indicates that the radio wave transmission power is weak, a control signal for instructing the radio wave transmission power switching circuit of the tuner 19 to switch the radio wave transmission power to weak is output. (Step S504),
The radio wave transmission power switching circuit of the tuner 19 switches the magnitude of the radio wave transmission power to weak if the current radio wave transmission power is strong.

As described above, when the value of the received electric field strength measured every one second continues to be the value of the reference level 1 or more for 5 seconds, that is, when the state of the received electric field strength is strong for a predetermined time,
When the radio wave transmission power is switched from strong to weak and the value of the received electric field strength measured every one second is less than the reference level 2, that is, when the received electric field strength is weak during the measurement of the received electric field strength. Occurs once, the electric power for transmitting radio waves is switched from weak to strong.

As described above, when the weak received electric field strength occurs once during the measurement of the received electric field strength, the weak electric field strength is intermittently changed because the electric wave transmission power is switched from the weak electric power to the strong electric power. In a radio wave environment that occurs, there is no fear that the radio wave transmission power will be kept weak, and it is difficult for noise to be included in the call voice.

Further, a digital radio D is used as a radio control signal for instructing the slave unit 42b of the magnitude of electric wave transmission power.
Since the signal of the channel is used, the transmission sound of the radio control signal is not heard during the call. Also,
The same effect can be obtained by using a radio signal having a frequency outside the voice band instead of the digital radio D channel signal. The MSK signal that is normally used can be used as the radio control signal, but the signal transmission sound is heard during a call.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. 6 and 7. FIG. 6 is a flowchart showing the control for the switching operation of the electric wave transmission power in the slave unit provided in the extension cordless telephone of the second embodiment of the invention, and FIG. 7 is the extension cordless telephone of the second embodiment of the invention. 5 is a flowchart showing control for switching operation of electric wave transmission power in the parent device provided in FIG.

The present embodiment has a master unit 42a and a slave unit 42b having the same configuration as the first embodiment, and the radio wave transmission power is increased to the tuner 12 of the master unit 42a and the tuner 19 of the slave unit 42b. There is provided a radio wave transmission power switching circuit (not shown) that selectively switches between three levels, medium and weak.

In the present embodiment, the switching operation control of the radio wave transmission power to the radio wave transmission power switching circuit of the tuner 19 is performed according to the received electric field strength measured by the control circuit 25 of the slave device 42b, and the radio wave is transmitted to the master device 42a. Sends the power output switching instruction. On the other hand, the control circuit 15 of the parent device 42a
Controls the switching operation of the radio wave transmission power by the radio wave transmission power switching circuit of the tuner 12 based on the radio wave transmission power switching instruction from the slave unit 42b.

Next, the control for the switching operation of the radio wave transmission power in the present embodiment will be described with reference to FIGS. 6 and 7.

In the control circuit 25 of the master unit 42a and the slave unit 42b during a call, as shown in FIG. 6, the reception electric field strength measured by the tuner 19 is taken in at a predetermined cycle, for example, every second, and the reception thereof is performed. The measured value of the electric field strength is converted into digital data by AD conversion (step S601).

Next, it is judged which reference level the measured value of the received electric field strength is (step S602).
S608). Specifically, it is determined whether or not the measured value of the received electric field strength is equal to or higher than the reference level 1 for 5 seconds (step S602), and the measured value of the received electric field strength is less than the reference level 2. Whether or not (step S60
8) and are performed. The reference level 1 and the reference level 2 are levels set in the same manner as the reference level 1 and the reference level 2 in the first embodiment.

When the measured value of the received electric field strength is a value of the reference level 1 or more for 5 seconds, that is, the received value of the received electric field strength is the value of the reference level 1 or more for five consecutive times (step S602), it is determined whether or not the magnitude of the current radio wave transmission power is set to strong or medium (step S603, step S606). If the magnitude of the radio wave transmission power is not set to strong or medium, it is determined that the received electric field strength that enables sufficient communication can be obtained with the radio wave transmission power of the currently set magnitude, that is, weak, and the process is restarted. It returns to S601.

When the magnitude of the electric wave transmission power is set to be strong (step S603), the received electric field strength that enables sufficient communication can be obtained with the strong electric wave transmission power.
It is determined that the magnitude of the radio wave transmission power can be switched while it is one step lower, and a control signal for instructing the radio wave transmission power switching circuit of the tuner 19 of the slave unit 42b to switch the radio wave transmission power inside is issued. (Step S604). By this control signal, the radio wave transmission power of the slave unit 42b is switched to the inside.

When the magnitude of the radio wave transmission power is set to the middle level (step S606), the reception electric field strength that enables sufficient communication is obtained with the radio wave transmission power of the medium magnitude.
It is determined that it is possible to switch the magnitude of the radio wave transmission power to one step lower, and a control signal for instructing the radio wave transmission power switching circuit of the tuner 19 of the slave unit 42b to switch the radio wave transmission power to weak is output. (Step S607). The radio signal transmission power of the slave unit 42b is weakly switched by this control signal.

If the measured value of the received electric field intensity is less than the reference level 2, that is, if the value of the received received electric field intensity becomes less than the reference level 2 even once (step S6).
08), it is determined whether or not the magnitude of the current radio wave transmission power is set to weak or medium (step S60).
9, step S611).

If the magnitude of the radio wave transmission power is set to be weak (step S609), it is determined that a weak radio wave transmission power will interfere with the call, and the radio wave transmission power switching circuit of the tuner 19 receives the radio wave. A control signal is issued to instruct to switch the output power by one step higher (step S610). By this control signal, the radio wave transmission power of the slave unit 42b is switched to the inside.

If the magnitude of the radio wave transmission power is set to medium (step S611), it is determined that the medium radio wave transmission power interferes with the call, and the radio wave transmission power switching circuit of the tuner 19 transmits the radio wave. A control signal is issued to instruct to switch the output power to a higher level by one step (step S612). The radio signal transmission power of the slave unit 42b is strongly switched by this control signal.

If the magnitude of the radio wave transmission power is not set to be weak or medium, that is, if the magnitude of the current radio wave transmission power is set to be strong (steps S609 and S61).
1) Since the radio wave transmission power cannot be further increased, the process returns to step S601 again.

In accordance with the measured value of the received electric field strength, the slave unit 42b
When the control for switching the radio wave transmission power is performed (step S604, step S607, step S610, step S612), a radio wave transmission power instruction for instructing the magnitude of the radio wave transmission power corresponding to the control is given by the wireless control signal. It is transmitted (step S605), and the process returns to step S601 again.

On the other hand, in the control circuit 15 of the parent device 42a, as shown in FIG. 7, when the wireless control signal from the child device 42b, that is, the radio wave transmission power instruction is received (step S7).
01), it is determined whether the radio wave transmission power instruction from the slave unit 42b indicates radio wave transmission power strong, during radio wave transmission power, or radio wave transmission power weak (step S702, step S704).

When the radio wave transmission power instruction from the slave unit 42b indicates a high radio wave transmission power, a control for instructing the radio wave transmission power switching circuit of the tuner 12 to strongly switch the radio wave transmission power level. A signal is issued (step S7)
03), the radio wave transmission power switching circuit of the tuner 12 switches the magnitude of the radio wave transmission power to strong if the magnitude of the current radio wave transmission power is weak or medium.

When the radio wave transmission power instruction from the slave unit 42b indicates that the radio wave transmission power is being supplied, a control for instructing the radio wave transmission power switching circuit of the tuner 12 to switch the magnitude of the radio wave transmission power to inside. A signal is issued (step S7)
05), the radio wave transmission power switching circuit of the tuner 12 switches the magnitude of the radio wave transmission power to the inside when the magnitude of the current radio wave transmission power is strong or weak.

When the radio wave transmission power instruction from the slave unit 42b indicates that the radio wave transmission power is weak, a control for instructing the radio wave transmission power switching circuit of the tuner 12 to switch the magnitude of the radio wave transmission power inside. A signal is issued (step S7)
06), the radio wave transmission power switching circuit of the tuner 12 switches the magnitude of the radio wave transmission power to weak if the current radio wave transmission power is strong or medium.

As described above, if the weak received electric field strength occurs once during the measurement of the received electric field strength, the electric wave transmission power is switched from weak to medium or strong, so that the weak received electric field strength is intermittent. In a radio wave environment that occurs in a dynamic manner, there is no longer a possibility that the magnitude of the radio wave transmission power is kept weak, and it is possible to make it difficult for noise to be introduced into the call voice.

In each of the above embodiments, the master device 42
In either a or the slave unit 42b, it is determined whether or not the switching of the radio wave transmission power is necessary or not according to the received field strength, but the master unit 42a and the slave unit 42b independently measure the received field strength. It is also possible to determine whether or not the radio wave transmission power needs to be switched according to the measured received electric field strength, and to control the switching of the radio wave transmission power.

Further, in each of the above-mentioned embodiments, the analog type cordless telephone is shown, but it goes without saying that the principle of the present invention can be applied to the digital type cordless telephone.

[0070]

As described above, according to the wireless communication device of the first aspect, the judgment range for the measured received electric field strength which requires the switching operation of the radio wave transmission power from the small to the large is the radio wave transmission power. The switching condition of the radio wave transmission power is determined based on the judgment condition that is set wider than the judgment range for the measured received electric field strength that requires the switching operation from large to small. Therefore, the weak electric field strength occurs intermittently. In such a radio wave environment, there is no fear that the magnitude of the radio wave transmission power is kept weak, and it is possible to obtain a radio wave environment in which noise is unlikely to be introduced into a call voice.

According to the radio communication device of the second aspect, whether or not the measured received electric field strength is equal to or higher than the first judgment level for the first judgment time or longer in the radio wave transmission power switching judgment. The first judgment and the second judgment whether the measured received electric field strength is lower than the second judgment level set lower than the first judgment level are performed, and the measured received electric field strength is first When the value equal to or higher than the judgment level continues for the first judgment time or longer, the radio wave transmission power is controlled to be switched from high to low, and the measured received electric field strength is lower than the second judgment level. Since the radio wave transmission power is controlled to switch from small to high, when a condition of weak received electric field strength that requires switching operation of the radio wave transmission power from small to large occurs, the radio wave transmission power is immediately changed from small to large. It is possible to execute the switching operation to That.

According to the wireless communication device of the third aspect, the reception electric field strength measuring means is provided in the master unit, and the master unit performs the radio wave transmission power switching judgment, and the radio wave transmission power corresponding to the radio wave transmission power switching judgment result. Can be instructed to the slave unit.

According to the radio communication device of the fourth aspect, the reception electric field strength measuring means is provided in the slave unit, and the slave unit performs the radio wave transmission power switching judgment and the radio wave transmission power corresponding to the radio wave transmission power switching judgment result. Can be instructed to the master unit.

According to the wireless communication device of the fifth aspect, the reception electric field strength measuring means is provided in each of the master unit and the slave unit, and the radio transmission power switching determination is performed in each of the master unit and the slave unit. be able to.

According to the wireless communication device of the sixth aspect, since the wireless signal having the frequency outside the voice band is used as the control signal for instructing the slave unit to switch the radio wave transmission power from the master unit, The transmission sound of the wireless control signal is not heard during the call.

According to the wireless communication device of the seventh aspect, since the signal of the digital wireless D channel is used as the control signal for instructing the slave unit to switch the radio wave transmission power from the master unit, the transmission of the wireless control signal is performed. No sound is heard during the call.

According to the wireless communication device of the eighth aspect, since the wireless signal having the frequency outside the voice band is used as the control signal for instructing the master unit to switch the radio wave transmission power from the slave unit, The transmission sound of the wireless control signal is not heard during the call. The transmission sound of the wireless control signal is not heard during the call.

According to the wireless communication device of the ninth aspect, since the signal of the digital wireless D channel is used as the control signal for instructing the master unit to switch the radio wave transmission power from the slave unit, the transmission of the wireless control signal is performed. No sound is heard during the call.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a telephone exchange device accommodating a first embodiment of a telephone device of the present invention.

2 is a block diagram showing a configuration of a base unit of the extension cordless telephone of FIG.

FIG. 3 is a block diagram showing a configuration of a slave unit of the extension cordless telephone of FIG.

FIG. 4 is a flowchart showing control for switching operation of electric wave transmission power in the parent device of the extension cordless telephone of FIG.

5 is a flow chart showing a control for a switching operation of electric wave transmission power in a slave unit of the extension cordless telephone of FIG.

FIG. 6 is a flowchart showing control for switching operation of radio wave transmission power in a handset provided in an extension cordless telephone according to a second embodiment of the present invention.

FIG. 7 is a flowchart showing control for switching operation of radio wave transmission power in a master unit provided in an extension cordless telephone according to a second embodiment of the present invention.

FIG. 8 is a flowchart showing the control of the switching operation of the radio wave transmission power switching means executed by the parent device of the conventional cordless telephone device.

[Explanation of symbols]

 12, 19 Tuner (electric wave transmission power switching means) 15, 25 Control circuit 21 Receiver 22 Microphone 42 Extension cordless telephone (wireless communication device) 42a Base unit 42b Handset

Claims (9)

[Claims] 1. A reception electric field strength measuring unit for measuring a reception electric field strength in at least one of a master unit and a slave unit that performs wireless communication with the master unit, and the master unit and the master unit according to the measured reception electric field intensity. In a wireless communication device comprising radio wave transmission power switching means for selectively switching the magnitude of radio wave transmission power in a slave unit, a judgment for the measured received electric field strength requesting a switching operation from the radio wave transmission power to the small one Radio communication characterized in that radio wave transmission power switching determination is performed based on a determination condition whose range is set wider than the determination range for the measured received electric field strength that requires a switching operation of the radio transmission power from large to small. apparatus. 2. The radio wave transmission power switching judgment is made by the first judgment as to whether or not the measured received electric field strength has maintained a value equal to or higher than a first judgment level for a first judgment time or longer. A second judgment whether the received electric field strength is lower than the second judgment level set lower than the first judgment level, and the measured received electric field strength is a value equal to or higher than the first judgment level. Is maintained for a first determination time or longer, the radio wave transmission power is controlled to be switched from high to low,
The radio communication device according to claim 1, wherein when the measured received electric field strength is lower than the second determination level, the radio wave transmission power is controlled to switch from small to large. 3. The reception electric field strength measuring means is provided in the master unit, and the master unit performs the radio wave transmission power switching judgment and switches the radio wave transmission power corresponding to the radio wave transmission power switching judgment result. The wireless communication device according to claim 1, wherein the wireless communication device is instructed to a child device. 4. The reception electric field strength measuring means is provided in the slave unit, and the slave unit performs the radio wave transmission power switching determination and switches the radio wave transmission power corresponding to the radio frequency transmission power switching determination result. The wireless communication device according to claim 1, wherein the wireless communication device instructs the master unit. 5. The reception electric field strength measuring means is provided in each of the master unit and the slave unit, and the radio wave transmission power switching determination is made in each of the master unit and the slave unit. The wireless communication device according to item 1 or 2. 6. A radio signal having a frequency in a region outside a voice band is used as a control signal for instructing switching of the radio wave transmission power from the master unit to the slave unit. Wireless communication device. 7. A digital wireless D channel signal is used as a control signal for instructing the slave unit to switch the radio wave transmission power from the master unit.
The wireless communication device described. 8. A radio signal having a frequency in a region outside a voice band is used as a control signal for instructing the master unit to switch the radio wave transmission power from the slave unit. Wireless communication device. 9. A digital wireless D channel signal is used as a control signal for instructing the master unit to switch the radio wave transmission power from the slave unit.
The wireless communication device described.