JP3432048B2 - Communication device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication device which detects that a communication channel is not used and communicates using the unused channel.

[0002]

2. Description of the Related Art In a conventional wireless communication system, it is determined whether or not a channel is used by using a predetermined carrier detection threshold value.

[0003]

However, in the above-mentioned conventional example, since there is only one threshold value for carrier detection, in order to extend the wireless communicable distance, even if the strength of the radio wave is weak, it is necessary for communication. We could not solve the problem that it must be recognized as a radio wave of the above and the problem that it must be usable even in a bad environment with unnecessary radio waves emitted from other electronic devices.

Therefore, a device designed to extend a communicable distance cannot be installed in a place where it is affected by other electronic devices, and even if it is installed, many failures occur.

In addition, a device designed so as not to be easily affected by other electronic devices has a shortcoming that a callable distance becomes short.

[0006]

The present invention has a plurality of carrier detection threshold values for determining whether or not a channel is used,
A communication device for detecting an unused channel from a plurality of communication channels and performing communication using the unused channel, and determining means for determining a channel to be used based on communication with a communication partner. And a receiving means for receiving a signal for designating any one of the plurality of threshold values from the communication partner, the threshold value can be set in an environment less affected by other electronic devices. It is possible to increase the ability to recognize the empty channel and extend the communication range, and to raise the threshold in a bad environment where there is a lot of influence from other electronic devices etc. , Furthermore, by receiving a signal for designating one of a plurality of threshold values from a communication partner,
The threshold specified by the communication partner can be used.

[0007]

1 is a block diagram of a wireless telephone system which is a specific example of a wireless communication system embodying the present invention.

This radio telephone system uses a main unit 101 that accommodates at least one external line and a plurality of internal lines and has a switching function, a communication function with the main unit 101, and at least one opposing slave unit and radio. Base unit 102 for communication
And a slave unit 103 that wirelessly communicates with the master unit.

The master unit 102 has a communication I / F (interface) unit 104 for communicating with the main unit 101, and a voice for performing processing such as secretly talking to the voice from the main unit 101 and the voice from the slave unit. Processing unit 105 and voice processing unit 105
Voice from the control unit 108 and control data from the control unit 108.
03, a receiver 106 that receives a voice signal and a control signal wirelessly sent from a slave unit, and a carrier detection that is set to one of a plurality of carrier detection levels. Setting unit 109 and control unit 108
And an antenna 110 that performs wireless transmission with the child device 103.

The control unit 108 controls the voice processing unit 105, the transmission unit 106, and the reception unit 107, and also controls the communication I / F.
Through the unit 104, the main device 101 and the transmitting / receiving units 106, 1
Communication and control with the child device 103 are performed through 07, and further operation is performed according to the setting of the carrier detection setting unit 109.

Further, the receiving section 107 has a reception electric field strength output section 111 which outputs a voltage having an analog value according to the strength of the radio wave being received, and the control section 108 digitally outputs the analog voltage value. A / D (analog /
It has a digital) conversion unit 112.

Next, the child device 103 has an antenna 121 for wireless transmission / reception with the parent device 102 and a microphone 12 for inputting voice.
2, a receiver 123 that outputs a voice, a voice processing unit 124 that performs processing such as secretly (or releasing) a voice from a microphone and a voice signal from a base unit, a voice from the voice processing unit 124, and A transmission unit 125 that wirelessly transmits control data from the control unit to the master device 102, a reception unit 126 that receives a voice signal and a control signal wirelessly transmitted from the master device 102, and a call origination / disconnection / dial. The keypad 128 for inputting information such as data, and the control unit 12
7 and a rechargeable battery 129.

The control unit 127 controls the voice processing unit 124, the transmission unit 125, and the reception unit 126, communicates with and controls the base unit 102 through the transmission / reception unit, and further operates according to the information input from the keypad 129. I do.

Further, the receiving unit 126 has a receiving electric field intensity output unit 130 for outputting a voltage having an analog value according to the strength of the radio wave being received, and the control unit 127 converts the analog voltage value into a digital value. It has an A / D converter 131 for converting.

Next, the operation of this embodiment will be described.

First, the control unit 1 of the master unit 102 and the slave unit 103
In 08 and 127, it is necessary to store a value that is a predetermined threshold value in advance.

In the case of an analog cordless telephone, the legal standard for carrier detection is to detect at 2 μVemf or more at the antenna receiving end, so that, for example, 1.5 at the antenna receiving end.
Add μVemf. At this time, the reception electric field output unit 11
The voltage values output from the terminals 1 and 130 are converted into the A / D converter 11
1, 131 converts into a digital value, and the value is stored in the storage units 108M and 127M in the control units 108 and 127.

Hereinafter, the carrier detection setting is made in two steps,
The setting is performed by turning on / off the changeover switch of the carrier detection setting unit 109. The threshold value for carrier detection is low when turned on and high when turned off.

FIG. 3 and FIG. 4 show the flow of incoming calls.

When an incoming call arrives at the outside line of the main unit 101 (S3
01), the master unit control unit 108 receives a notification from the control unit of the main device 101 through the communication I / F unit 104 (S30).
2). In response to this, the base unit control unit 108 causes the reception unit 10 to
7 is set as a channel for communicating with the child device 103 (S303). Then, the output voltage of the reception electric field output unit 111 converted into a digital value by the A / D conversion unit 112 is detected (S304). Here, the carrier detection setting unit 10
When the switch of 9 is off (high threshold value) (S3
05), the received electric field strength and the first threshold value (first in the storage unit 1
The value stored in 08M) is compared (S307). When the switch of the carrier detection setting unit 109 is on (the threshold value is low), a certain constant value is subtracted from the second threshold value (the stored value (first threshold value)). Value) is compared (S306).

Here, the numerical value subtracted from the stored value is
It is determined in advance as follows. For example, when 1.5μVemf is added to the antenna receiving end and 1.0μVem
If the difference between the values obtained by converting the voltage output from the reception electric field output unit 111 into a digital value when f is added is 3, it is subtracted by 3.

When 1.5 μVemf is added, it is 1.0
Both values may be stored when μVemf is added.

As described above, when the value of the received electric field level converted into a digital value by comparing with the respective values by the switch of the carrier detection setting unit 109 is small, there is no carrier in the channel, so the slave unit 103. It is determined that it can be used for communication with (S308). If big,
It is determined to be unusable, and the receiving unit 111 is set to another communication channel to search for an available channel (S309).

Next, the master unit control unit 108 sets the receiving unit 107 as a control channel for transmitting control data to the slave unit 103 (S310). Then, the output voltage of the reception electric field output unit 111 converted into a digital value by the A / D conversion unit 112 is detected (S311) and compared with the threshold value (S31).
2, S313, S314). As a result, if the value obtained by converting the received electric field level into a digital value is small (S31
5), it is determined that there is no carrier in the control signal channel, and control data (incoming call notification) is wirelessly transmitted to the child device 103 (S317). If it is larger, it is determined that there is a carrier, and the incoming call notification is not performed (S316). The data to be transmitted at this time includes the information of the channel used for the communication previously searched for and the information of whether the carrier detection setting is on the higher threshold side or the lower threshold side in the incoming notification information.

Upon receiving the wireless data from the master unit, the control unit 127 of the slave unit 103 (S318) stores information on whether the threshold value is high or low in the storage unit 127M in the control unit 127 (S319). The receiving unit 126 is provided on the channel that responds to the base unit (the channel notified from the base unit).
Is set (S320). Then, the output voltage of the reception electric field intensity output unit 130 converted into a digital value by the A / D conversion unit 131 is detected (S321).

Then, according to the threshold value sent from the master unit, whether the threshold value is high or low (S322), if the threshold value is high, it is compared with the third threshold value (value stored in the storage unit 127M) ( S324), if lower, it is compared with a fourth threshold value (value obtained by subtracting a predetermined value from the stored value (third threshold value)) (S323). As a result, if the received digital value of the electric field level is small (S325), it is determined that there is no carrier, and the response data is wirelessly transmitted to the parent device 102 (S328). If it is larger, the child device 103 does not respond and enters the control data standby state (S326, S327).

After transmitting the control data to the child device 103, the parent device 102 switches to the communication channel for both transmission and reception. Here, when the master device 102 normally receives the response from the slave device 103, the master device 102 shifts to the call state (S329). or,
If the base unit 102 does not receive a response from the handset unit 103, it is determined that the specified communication channel cannot be used, and the receiving unit 10 uses another channel to search for a usable channel.
7 is set (S303).

At the time of making a call from the child device 103, FIG. 5 to FIG.
The flow is as shown in.

When the call key of the keypad 129 of the slave 103 is pressed (S401), the slave controller 127 sets the receiver 126 as a channel for transmitting control data to the master 102 (S402). . Then, the reception electric field output unit 130 converted into a digital value by the A / D conversion unit 131
The output voltage of is detected (S403). Here, it is compared whether this value is larger or smaller than the threshold value (S40
4) The threshold value at this time depends on the information stored in the storage unit 127M in the control unit 127 whether the call before the calling operation was made with a high threshold value or a low threshold value. , The threshold value on the same side as the previous call is selected (S405, S406).

If there is no information on the previous call, such as immediately after the power is turned on, this call is selected from a predetermined initial value (for example, a high threshold value).

As a result of the comparison between the received electric field level and the threshold value, when it is determined that there is no carrier (S407), the control unit 127 of the slave 103 transmits control data to the master 102 (S409). When it is larger, it is determined that there is a carrier, control data transmission is not performed, and a call key invalidation notification is visibly or audibly issued (S408).

The control unit 1 of the base unit 102 which receives the control data
08 sets the receiving unit 107 to the channel for communicating with the slave 103 (S410). Then, the A / D converter 1
The output voltage of the reception electric field output unit 111 converted into a digital value in 12 is detected (S411). Here, according to the switch of the carrier detection setting unit 109 (S412), it is compared with a high threshold value (S414) or a low threshold value (S413). If the received digital value of the electric field level is small, it is determined that there is no carrier (S415).
Then, the response data is transmitted to the child device 103 through the control channel (S417). This data includes information as to whether the carrier detection setting unit 109 is set to the high threshold side or the low threshold side and the carrierless communication channel information found in the above operation. ing. If it is larger, it is determined that there is a carrier, and the reception unit 107 is set to another communication channel to search for an unused channel (S416).

Upon receiving the response data from the master unit 102, the control unit 127 of the slave unit 103 (S418) sets the receiving unit 126 to the communication channel instructed by the master unit 102 (S419). In addition, the information indicating whether the carrier detection level is high or low, which is sent from the parent device 102, is stored in the storage unit 127M in the control unit 127 (S420).

Then, the output voltage of the reception electric field output unit 130 converted into a digital value by the A / D conversion unit 131 is detected (S421). Here, according to the detection level information sent from the parent device 102 (S422), the threshold value and the digital value of the received electric field level are compared (S423, S42).
4). If the value of the reception electric field level is smaller than the threshold value (S425), it is determined that there is no carrier, and the response data is transmitted to the master device 102 through the communication channel (S4).
28).

After sending the control data to the child device 103, the parent device 102 switches to the communication channel for both transmission and reception. Here, when the master unit 102 normally receives the response from the slave unit 103, the master unit 102 shifts to the call state (S429).

If it is larger, it is determined that there is a carrier, the slave 103 does not send the response data (S426), and enters the control channel reception standby state (S427). If the base unit 102 cannot receive a response from the handset unit 103, it is determined that the specified communication channel cannot be used, and the receiving unit is set to another channel in order to search for a usable channel (S4).
10).

Next, the second embodiment will be described.

FIG. 2 is a block diagram of a second wireless communication system embodying the present invention. 201 to 204 are voltage comparators. The other parts correspond to the numbers in FIG.

In this embodiment, it is necessary to preset the logic of the comparator so that it is inverted at a predetermined threshold value.
Therefore, for example, 1.5 μVemf is applied to the antenna receiving end.
Is added, and the value is compared by the comparator 201 (main unit 102 side), 20
3 (slave unit 103 side) is set to be inverted.
Further, for example, 1.0 μVemf is added to the antenna receiving end and the logic of the comparators 202 (main unit 102 side) and 204 (slave unit 103 side) is set to be inverted by the value.

When the threshold value is high, the comparator 201
(Or 203) output, and if the threshold value is low, output is output from the comparator 202 (or 204).

In the above description of the embodiment, the carrier detection level setting unit 109 is provided on the master unit 102 side, but it may be provided on the slave unit 103 side, or the master unit 102 side and the slave unit 10 may be provided.
It may be provided on both of the three sides or in the main device 101.

In the present embodiment, the setting is made by operating the carrier detection level setting unit 109 provided in the base unit 102, but it may be set by another extension telephone connected to the main unit 101.

[0043]

As described above, according to the present invention,
In a communication device that detects an unused channel from a plurality of communication channels and performs communication using the unused channel, by having a plurality of carrier detection threshold values for determining whether or not the channel is used, In an environment with little influence from other electronic devices, etc., it is possible to lower the threshold value, enhance the ability to recognize an empty channel, and extend the communicable distance. In many bad environments, it is possible to solve two contradictory problems by increasing the threshold value and allowing communication to extend the communicable distance and enable use in noisy environments. Furthermore, by receiving a signal for designating one of a plurality of threshold values from the communication partner, the threshold value designated by the communication partner can be used. There is.

In particular, by storing the threshold value of the electric field strength output section according to the strength of the received radio wave, it is possible to determine that the channel is in use regardless of the variation in the performance of the parts. The threshold value can be adjusted accurately according to the standard.

Further, by communicating a signal for designating one of the plurality of thresholds, it is possible to reliably designate the threshold when confirming an empty channel at each of the plurality of terminals. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a wireless telephone device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a wireless telephone device according to a second embodiment of the present invention.

FIG. 3 is a flowchart (No. 1) showing the processing when an incoming call is received according to the embodiment.

FIG. 4 is a flowchart (No. 2) showing the processing when an incoming call is received according to the embodiment.

FIG. 5 is a flow chart (No. 1) showing processing when a call is made in the embodiment.

FIG. 6 is a flowchart (No. 2) showing the processing at the time of calling according to the embodiment.

FIG. 7 is a flowchart (No. 3) showing the processing at the time of calling according to the embodiment.

[Explanation of symbols]

101 Main device 102 base unit 103 cordless handset 108 control unit 109 Carrier detection setting section 110 antenna 111 Received field strength output unit 112 A / D converter 130 Received electric field strength output unit

Continuation of the front page (56) Reference JP-A-8-322077 (JP, A) JP-A-4-216226 (JP, A) JP-A-6-90205 (JP, A) JP-A-6-197079 (JP , A) JP 64-80135 (JP, A) JP 2-219326 (JP, A) JP 2-260930 (JP, A) JP 60-254933 (JP, A) JP 62-226729 (JP, A) JP 5-316036 (JP, A) JP 3-73628 (JP, A) JP 5-292019 (JP, A) JP 2-190039 (JP, A) JP-A-62-190039 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04B ^7/ 24-7/26 102 H04Q ^7/ 00-7/38

Claims (13)

(57) [Claims] 1. A plurality of carrier detection threshold values for determining whether or not a channel is used, an unused channel is detected from a plurality of communication channels, and communication is performed using the unused channel. A communication device for performing, deciding means for deciding a channel to be used based on communication with a communication partner, and receiving means for receiving a signal for designating any one of the plurality of threshold values from the communication partner. A communication device comprising: 2. The communication device according to claim 1, wherein the communication device accommodates at least one outside line and at least one extension line, is accommodated in a main device having a switching function, and faces the communication function with the main device. A communication device, which is a cordless telephone system including a master unit that wirelessly communicates with two slave units and at least one slave unit that wirelessly communicates with the master unit. 3. The master device according to claim 1, wherein the communication device accommodates at least one outside line and uses a master device that wirelessly communicates with at least one opposite slave device, and the master device and the wireless device. A communication device, which is a cordless telephone system including at least one child device that performs communication. 4. The means for determining the presence / absence of a carrier according to claim 1, wherein a digital value obtained by A / D conversion of an analog voltage output from the electric field strength output unit according to the strength of the received radio wave and a digital value in advance are used. A communication device characterized by performing comparison with a stored predetermined value. 5. The determination as to the presence or absence of a carrier according to claim 1, further comprising a plurality of voltage comparators having an analog voltage output from an electric field intensity output unit as an input according to the intensity of a received radio wave. A communication device, characterized in that it is performed by selecting one of the outputs of the container. 6. The communication device according to claim 1, wherein the output of the electric field strength output unit according to the strength of the received radio wave is stored as a threshold value. 7. The communication device according to claim 1, wherein the output of the electric field strength output unit for radio waves having different strengths is stored as each of a plurality of threshold values. 8. The threshold according to claim 1, wherein the output of the electric field strength output unit according to the strength of the received radio wave is stored as one of a plurality of thresholds, and another threshold is stored. A communication device characterized by being calculated from. 9. The communication device according to claim 1, further comprising means for communicating a radio signal. 10. In a communication system in which a plurality of terminals detect an unused channel and perform communication using the unused channel, a plurality of threshold values for carrier detection for determining whether or not the channel is used are provided, and A communication system characterized in that a designated signal designating one of the thresholds is communicated between a plurality of terminals, and whether or not a channel is used is judged using the threshold designated by the designated signal. 11. The communication system according to claim 10, wherein the designation signal is included in an incoming call notification. 12. The communication system according to claim 10, wherein the output of the electric field strength output unit according to the received radio wave is stored as a threshold value. 13. The use of a channel according to claim 10, wherein a storage unit that stores a result designated by the designation signal and a threshold value used in the previous communication stored in the storage unit are used. A communication system characterized by the above.