JP3041224B2 - Wireless communication device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication apparatus for removing a high frequency component contained in a received voice signal.

[0002]

2. Description of the Related Art Conventionally, in a telephone device having a master unit and a slave unit for performing wireless communication with the master unit, that is, a so-called cordless telephone device, a predetermined level of communication between the master unit and the slave unit is enabled. A high-frequency component removing means for removing high-frequency components contained in the received audio signal is provided in each of the master unit and the slave unit, and the reception electric field strength is lower than the reference level.
If the value is too high, the high frequency component
If the field strength is above its reference level,
The component removing means has been stopped .

[0003]

However, in the conventional cordless telephone device, the activation and removal of the high frequency component removing means are performed.
Field strength fluctuates near the reference level where
Under such circumstances, start and stop of the high frequency component removal means
The call is repeatedly stopped, the sound quality is reduced, and the call goes smoothly.
Could not.

It is an object of the present invention to activate and deactivate damping means.
So that the electric field strength fluctuates near the reference level where
It is an object of the present invention to provide a wireless communication device capable of preventing a decrease in sound quality under a circumstance .

[0005]

According to the first aspect of the present invention,
Detecting means for detecting a received electric field intensity, and attenuation means for attenuating high frequency components of the received audio signal, said detecting means
The received electric field strength detected is lower than the predetermined reference level.
Control means for activating the damping means on condition that
And the control means receives the signal detected by the detection means.
The condition that the signal strength is not less than the predetermined reference level
In addition to the above, the reception electric field strength is the predetermined reference level.
The condition that the condition that is not less than continues for a predetermined time is satisfied
And stopping the damping means .

According to a second aspect of the present invention, there is provided a detecting means for detecting a received electric field intensity, an attenuating means capable of switching an intensity of an attenuating process for attenuating a high frequency component of a received voice signal, and a detecting means for detecting the received electric field. Control means for instructing the attenuating means to perform a strong attenuation process on condition that the received electric field strength obtained is less than a second reference level lower than the first reference level, wherein the control means comprises: In addition to the condition that the reception electric field strength detected by the detection means is not less than the second reference level, the condition that the state where the reception electric field strength is not less than the second reference level continues for a predetermined time, and the reception electric field strength When the condition that is less than the first reference level is satisfied, the controller instructs the attenuation means to perform a weak attenuation process, and the received electric field strength detected by the detection means does not fall below the second reference level. In addition to the conditions that, conditions the state the received electric field strength is not less than the second reference level continues for a predetermined time, conditions the received signal strength is not less than said first reference level, and the reception electric field strength is the First
When the condition that the state is not less than the reference level is continued for a predetermined time is satisfied, the stop of the attenuation means is instructed.

[0007] The invention described in claim 3 is claim 1 or 2.
The wireless communication device described in the above, the parent device and the parent device
A slave unit for performing wireless communication, wherein the master unit and the slave unit
The detection means, the attenuation means, and the control means, respectively.
Are provided .

[0008]

[0009]

[0010]

[0011]

[0012]

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 apparatus accommodating an extension cordless telephone which is a first embodiment of the wireless communication apparatus of the present invention.

As shown in FIG. 1, the telephone exchange device 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
And A plurality of extension dedicated telephones 41 and a plurality of extension cordless telephones 42 are connected to the extension interface 5, and each extension cordless telephone 42 has a base station 42a and a wireless communication device having a slave unit 42b for performing wireless communication with the base station 42a. Consists of

The voice information from each of the digital interface 7, analog interface 8, and extension interface 5 is exchanged within the communication path 6, and the digital interface 7, analog interface 8, extension interface 5 and the control of 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 control of the control circuit 9.
AM11 is used.

Next, the configuration of the extension cordless telephone 42 will be described with reference to FIGS. FIG. 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 slave unit 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 3 and the tuner 12 via the interface 14 and the voice processing circuit 13.

The audio processing circuit 13 performs a predetermined process on the audio information. The tuner 12 modulates the audio information with a radio wave of a predetermined frequency and then transmits the modulated radio wave from the antenna. The tuner 12 demodulates the radio wave received from the slave unit from the slave unit and then transmits the demodulated radio wave to the audio processing circuit 13. I do. The tuner 12 has a measuring circuit (not shown) for measuring a received electric field intensity indicating the intensity of a radio wave received by the antenna.
And a high-frequency component removing circuit (not shown) for removing high-frequency components contained in the audio signal received from the slave unit 42b. The high-frequency component removing circuit comprises a filter circuit for attenuating frequency components of a predetermined frequency or higher.

The interface 14, the audio processing circuit 13,
Control for 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 includes the ID information of the extension cordless telephone and the like.
It is stored in the EPROM 17. The control circuit 15
The work area for the arithmetic processing necessary for the control of
8 is used.

The control program stored in the ROM 16 includes a program for controlling the start and stop of the high frequency component removing circuit of the tuner 12 in accordance with the measured received electric field strength. Then, it is determined whether or not the measured reception electric field strength is lower than the reference level, and the measured reception electric field strength is maintained at a value equal to or higher than the reference level for a predetermined time (in this embodiment, set to 1 second). And if the measured received electric field strength is lower than the reference level, a control signal for instructing the high-frequency component removal circuit to start is output, and the measured received electric field strength becomes the reference level. If the above value is maintained for a predetermined time, a control signal for instructing the high frequency component removing circuit to stop is output.

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

As shown in FIG. 3, the slave unit 42b is
And a tuner 19 for performing wireless communication with the base station 2a. The tuner 19 modulates audio information from the audio processing circuit 20 with a radio wave of a predetermined frequency, and then transmits the modulated information to the master unit 42a from the antenna. And demodulates the radio wave received from the slave unit and transmitted to the audio processing circuit 20 after the demodulation. The tuner 19 includes a measuring circuit (not shown) for measuring a received electric field intensity indicating the intensity of a radio wave received by the antenna, and a tuner 19 for removing high frequency components contained in the audio signal received from the master unit 42a. And a high frequency component removing circuit (not shown). The high frequency component removing circuit comprises a filter over circuit for attenuating a predetermined frequency or higher frequency components.

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

Control of each of the microphone 22, the receiver 21, the audio 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 and the like. 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. The RAM 29 is used as a work area for arithmetic processing necessary for control of the control circuit 25.

The control program stored in the ROM 27 includes, like the master unit 42a, the activation of the high frequency component removing circuit of the tuner 19 in accordance with the measured received electric field strength.
A program for controlling stop is included.

Next, control for starting and stopping the high frequency component removing circuit in the extension cordless telephone 42 will be described with reference to FIG. FIG. 4 is a flowchart showing the control for starting and stopping the high frequency component removing circuit in the base unit of the extension cordless telephone of FIG. The control for starting and stopping the high-frequency component removing circuit by the control circuit 15 of the master unit 42a and the control for starting and stopping the high-frequency component removing circuit by the control circuit 25 of the slave unit 42b are the same. In the embodiment, control by the control circuit 15 of the master unit 42a will be described.
The description of the control by the control circuit 25 of b is omitted.

In the control circuit 15 of the master unit 42a during a call with the slave unit 42b, first, as shown in FIG. 4, the measured value of the received electric field strength measured by the tuner 12 is converted into digital data by AD conversion. (Step S40
1).

Next, it is determined whether or not the measured value of the received electric field strength is less than the reference level, and whether or not the measured value of the received electric field strength is maintained at the reference level 1 or more for one second. Is performed (steps S402 and S404). This reference level is a reference value for judging whether or not the received electric field strength is strong enough to prevent noise from entering. If the received electric field strength is a value equal to or higher than the reference level, the received electric field strength is determined. Is determined to be strong enough to prevent noise from entering, and if the received electric field strength is a value less than the reference level, it is determined to be weak enough to increase the possibility of noise entry.

If the measured value of the received electric field strength is less than the reference level (step S402), a control signal for instructing the high frequency component removing circuit to start is output (step S402).
403), the high frequency component removing circuit is activated by this control signal.

On the other hand, if the measured value of the received electric field strength is higher than the reference level for one second (step S4).
04), a control signal for instructing the high frequency component removing circuit to stop is output (step S405), and the high frequency component removing circuit is stopped by this control signal.

Next, when a control signal instructing start or stop is output to the high frequency component removing circuit, the process returns to step S401.

As described above, when the measured value of the received electric field strength falls below the reference level, the high frequency component removing circuit is activated, and the measured value of the received electric field strength is set to a value equal to or higher than the reference level by one. If it lasts for 2 seconds, the high-frequency component removal circuit is stopped, so that the high-frequency component removal circuit is activated immediately, and the value of the received electric field strength measured after the activation of the high-frequency component removal circuit is equal to the reference level. If the above value is not maintained for 1 second, the high frequency component removing circuit is not stopped, and when the received electric field strength fluctuates near the reference level during a call, the high frequency component removing circuit is activated. Switching in which stop and repetition are alternately repeated is suppressed. As a result, the number of times of alternately repeating the start and stop of the high-frequency component removing circuit is reduced, and it is possible to prevent the signal sound accompanying the switching from becoming noise and entering the call voice. It is possible to obtain a communication environment in which noise hardly enters even when the electric field strength is near the reference level. In other words, both noise attenuation and sound quality maintenance
A possible call environment is provided.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a flowchart showing the control for starting and stopping the high frequency component removing circuit in the extension cordless telephone according to the second embodiment of the present invention.

The present embodiment has a master unit 42a and a slave unit 42b having the same configuration as the first embodiment, and the tuner 12 of the master unit 42a and the tuner 19 of the slave unit 42b include the high frequency component removing circuit in two stages of strength the strength of the attenuation process for the high frequency components consisting switchable filter over circuit is provided that is.

[0035] In this embodiment, activation of the high-frequency frequency component removing circuit, the control for stopping the determination measurements whether lower than the reference level 2 value of the reception field strength, a measurement of received signal strength Is determined to have decreased to a value lower than reference level 1 higher than reference level 2 while the value of reference level 2 or higher has been maintained for a predetermined time (set to one second in the present embodiment). And whether the measured value of the received electric field strength has maintained a value equal to or higher than the reference level 1 for a predetermined time (set to one second in the present embodiment), and according to the result of each determination. Control the start and stop of the high frequency component removal circuit.

The reference level 1 and the reference level 2 are
This is a reference value for judging whether or not the received electric field strength is strong enough to prevent noise from entering. If the received electric field strength is a value equal to or higher than the reference level 1, the received electric field strength indicates that the noise has not entered. It is judged to be strong enough to be difficult. On the other hand, if the reception electric field strength is a value between the reference level 1 and the reference level 2, it is determined that the possibility of noise intrusion is slightly high, and the reception electric field strength is lower than the reference level 2. If the value is a value, it is determined that the possibility of noise intrusion is high enough.

Next, activation of the high-frequency frequency component removing circuit of the present embodiment will be described with reference to FIG. 5 the control for stopping. The control for starting and stopping the high-frequency component removing circuit by the control circuit 15 of the master unit 42a and the control for starting and stopping the high-frequency component removing circuit by the control circuit 25 of the slave unit 42b are the same. In the embodiment, control by the control circuit 15 of the master unit 42a will be described, and description of control by the control circuit 25 of the slave unit 42b will be omitted.

In the control circuit 15 of the master unit 42a during a call with the slave unit 42b, first, as shown in FIG. 5, the measured value of the received electric field strength measured by the tuner 12 is converted into digital data by AD conversion. (Step S50
1).

Next, it is determined whether or not the measured value of the received electric field strength is lower than the reference level 2 (step S502).
When the measured value of the received electric field strength is maintained at a value equal to or higher than the reference level 2 for one second, it is determined whether or not the measured value has decreased to a value lower than the reference level 1 and higher than the reference level 2 (step S50).
4, S505), and a determination is made as to whether the measured value of the received electric field strength has maintained the value equal to or higher than the reference level 1 for one second (step S507).

If the measured value of the received electric field strength is less than the reference level 2 (step S502), a control signal for instructing the high frequency component removing circuit to start and perform strong attenuation processing is output (step S503). The control signal activates the high frequency component removal circuit, and the intensity of the attenuation process is set to high.

When the measured value of the received electric field intensity is maintained at a value equal to or higher than the reference level 2 for one second, the value decreases to a value lower than the reference level 1 higher than the reference level 2 (step S5)
04, S505), a control signal for instructing activation and weak attenuation processing to the high-frequency component removal circuit is output to the high-frequency component removal circuit (step S506), and the high-frequency component removal circuit is activated by this control signal, and the intensity of the attenuation processing is increased. Is set to weak.

If the measured value of the received electric field intensity has maintained the value equal to or higher than the reference level 1 for one second (step S507), a control signal for instructing the high frequency component removing circuit to stop is output (step S508). The high frequency component removing circuit is stopped by this control signal.

Next, when a control signal for starting or stopping is output to the high frequency component removing circuit, the process returns to step S501.

[0044] Thus, the high-frequency after the strength of the attenuation process of the frequency component removal circuit is set to the intensity, the measurement value is the reference level 2 or more values of the reception field intensity lasts 1 sec and the reference level Since the switching to the weak level is not performed until the value falls below the reference level 1 higher than 2, the switching of the strength of the attenuation processing does not occur frequently, and the signal sound accompanying this switching becomes noise. To prevent the user from getting into the call voice.

[0045]

As described above, according to the wireless communication apparatus of the first aspect, the reception electric field strength is set to the predetermined reference level.
When the damping means is activated on condition that it is less than
That the received electric field strength is not less than the predetermined reference level.
In addition to the conditions, if the received electric field strength is
If the condition that no state continues for a predetermined time is satisfied,
Since the means is stopped, when the damping means is started,
The electric field strength fluctuates around a predetermined reference level.
The start and stop of the damping means is repeated even in difficult situations
To prevent the sound quality from deteriorating.

According to the second aspect of the present invention, the use of the attenuating means capable of switching the intensity of the attenuation process for attenuating the high frequency components of the received voice signal enables a fine height corresponding to the received electric field strength. Band frequency components can be removed, and a strong attenuation process is performed on condition that the received electric field strength is lower than a second reference level lower than the first reference level. In addition to the condition that the electric field strength is not less than the second reference level, the condition that the state where the received electric field strength is not less than the second reference level continues for a predetermined time and the condition that the received electric field strength is less than the first reference level are When the condition is satisfied, the attenuation process is stopped, and in addition to the condition that the received electric field strength is not less than the second reference level, the condition that the state where the received electric field strength is not less than the second reference level continues for a predetermined time Conditions reception field strength is not less than the first reference level, and received signal strength first reference Les
By performing when the condition that the state is not less than the bell continues for a predetermined time is satisfied, even in a situation where the received electric field strength fluctuates near the first or second reference level, it is possible to prevent the change of the attenuation process from being repeated, It is possible to prevent the sound quality from deteriorating.

According to the wireless communication device of the third aspect, the parent device
Detection means, attenuation means, and control
By providing a step, both the master unit and the slave unit
The effects of claims 1 and 2 can be obtained.

[0048]

[0049]

[0050]

[0051]

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a telephone exchange device accommodating an extension cordless telephone which is a first embodiment of a wireless communication device of the present invention.

FIG. 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 starting and stopping of a high frequency component removing circuit in a base unit of the extension cordless telephone of FIG. 2;

FIG. 5 is a flowchart showing control for starting and stopping of a high frequency component removing circuit in an extension cordless telephone according to a second embodiment of the present invention.

[Explanation of symbols]

12, 19 tuner ( detecting means, attenuating means, receiving electric field strength measuring means, high frequency component removing means) 15, 25 control circuit (control means) 21 receiver 22 microphone 42 extension cordless telephone (wireless communication device) 42a master unit 42b Cordless handset

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04B 1/00 H04B 7/26 H04M 1/00 H04Q 7/00

Claims (3)

(57) [Claims] 1. A reception detecting means for detecting the field intensity, and attenuation means for attenuating high frequency components of the received audio signal, said detected by the detection means the received signal strength given group
Activating the damping means on condition that it is less than the sub-level
Control means for controlling the reception power detected by the detection means.
The condition that the field strength is not less than the predetermined reference level
In addition, the reception electric field strength is lower than the predetermined reference level.
If the condition that the non-
A wireless communication device for stopping the attenuation means . 2. A detecting means for detecting a received electric field intensity, an attenuating means capable of switching an intensity of an attenuating process for attenuating a high frequency component of a received audio signal, and a receiving electric field strength detected by the detecting means. Control means for instructing the attenuation means to perform a strong attenuation process on condition that it is less than a second reference level which is lower than the first reference level, wherein the control means is detected by the detection means The reception electric field strength is the second
In addition to the condition that the received electric field intensity is not less than the second reference level, the condition that the state where the received electric field intensity is not less than the second reference level continues for a predetermined time and the condition that the received electric field intensity is less than the first reference level are satisfied. When the received electric field intensity detected by the detection means is in the second
In addition to the condition that the received electric field intensity is not less than the second reference level, a condition that the state where the received electric field intensity is not less than the second reference level continues for a predetermined time, the condition that the received electric field intensity is not less than the first reference level, and Received electric field strength
A wireless communication apparatus, wherein when the condition that the state is not lower than the first reference level continues for a predetermined time is satisfied, an instruction to stop the attenuation unit is issued. 3. A base unit and a child performing wireless communication with the base unit.
And the above-mentioned detection is provided to each of the master unit and the slave unit.
And detecting means the damping means and said control means is eclipsed set
The wireless communication apparatus according to claim 1 or 2, characterized in that that.