JP2567755B2 - Wireless phone call channel setting method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio telephone constituted by a base unit connected to a telephone line and a handset unit which communicates by radio, and more particularly to a call channel setting method.

[0002]

2. Description of the Related Art A telephone device called a wireless telephone, which is composed of a base unit connected to a telephone line and a handset that communicates wirelessly, is widely used. Such a wireless telephone is provided with a plurality of frequency channels for communication between the master unit and the slave unit, and one of the channels is selected for communication. Then, in such a device, it is necessary to detect whether or not the channel used for communication is an empty channel. Therefore, in such a wireless telephone, in order to select an idle channel during a call, it is configured to perform idle determination of the idle call channel during standby and store the number information of the idle call channel in advance. For example, one disclosed in Japanese Examined Patent Publication No. 1-125656 is known.

Further, in the wireless telephone, after the communication is performed using the frequency of the control channel provided for the collation operation between the master unit and the slave unit at the start of the call, the above-mentioned call channel is set. Is configured to be used to make a call operation.

[0004]

In the wireless telephone,
Since the call operation is started after performing the collating operation between the master unit and the slave unit by using the control channel described above, the collating operation is not performed when the control channel is in use, so the call can be performed. There is a problem of not Since the use time of such a control channel is set to a short time necessary for performing the matching operation according to the standard, the control channel returns to the unused state in the normal operation state. Therefore,
By waiting for a short time, the matching operation is performed by using the control channel, and the call operation can be started. However, in the following cases, there is a problem that the matching operation cannot be performed and the call operation cannot be started. That is, when two wireless telephones are in a call state at a short distance, the frequencies of the call channels used by the respective telephones are set to F and f, and a harmonic wave twice as high as the radio wave output from the transmission circuit is set. Considering this, the frequencies of the channels which are judged to be in use in the receiving circuit incorporated in the radio telephones different from these two radio telephones are F, f, 2
× F−f and 2 × f−F are considered, and the frequency F in them is considered.
And f are different from the frequency of the control channel, but 2 × F
The -f and 2xf-F frequencies may match the frequency of the control channel, in which case the radiotelephone cannot be used until the call of at least one radiotelephone has ended. become. The present invention intends to provide a method for setting a call channel that solves such a problem.

[0005]

According to the present invention, the frequency of the channel for communication is set to A,
C is the frequency of the control channel used only at the beginning of the call
Then, the communication channel is set by determining whether or not the channels of frequency A, frequency 2 × A−C and frequency (A + C) / 2 are used.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram incorporated in a master unit of a wireless telephone to which the call channel setting method of the present invention is applied. In the figure, 1 is a hybrid circuit for connecting a telephone line to a base unit, 2 is a transmission circuit for transmitting a control signal and a call signal to a handset, and 3 is an operation for receiving a signal transmitted from the handset. The receiving circuit 4 for controlling the operation of the circuit incorporated in the master unit is a control circuit for controlling the operation of the circuit incorporated therein, and the reference numeral 5 is a channel designating circuit for designating the transmitting and receiving channels of the transmitting circuit 2 and the receiving circuit 3 by the control operation of the control circuit 4. Yes,
It is composed of a synthesizer circuit. 6 is a vacancy judging circuit for judging whether or not the channel specified by the channel specifying circuit 5 is vacant based on the signal output from the receiving circuit 3, and 7 is a judgment operation by the vacancy judging circuit 6. , A channel memory circuit for storing the number information of the channel determined to be an empty channel.

In such a circuit configuration, the vacancy judging circuit 6 judges that the channel is vacant when, for example, the carrier level of the received signal received by the receiving circuit 3 is below a predetermined value. .

A call channel setting operation in the above-mentioned circuit configuration will be described with reference to the flow chart shown in FIG. First, the communication channel (frequency A) is set by the operation of the control circuit 4 (step A). When such a setting operation is performed, the function of the channel designating circuit 5 causes the receiving circuit 3 to receive the signal of the frequency A. When the receiving circuit 3 is in the state of receiving the signal of the frequency A, the vacancy judging circuit 6 judges whether or not the channel of the frequency A is vacant (step B). Frequency A
When the signal of 1 is received by the receiving circuit 3, the carrier level of the received signal becomes higher than a predetermined value, so the vacancy judging circuit 6 judges that the set communication channel is in use. As a result, the operation of setting the other communication channels is performed by the operation of the control circuit 4, and the operation of setting the other communication channels is performed, for example, every three channels.

If it is determined in step B that the set communication channel (frequency A) is an empty channel, then the channel whose frequency is 2 × A-C (however, C
Determines whether or not the frequency of the control channel) is empty (step C). Such operation is performed by the channel switching operation of the channel designation circuit 5 under the control of the control circuit 4. When such a switching operation is performed, the receiving circuit 3 is in a state of receiving a signal of frequency 2 × A-C. If the carrier level of the signal received by the receiving circuit 3 is detected and it is judged by the vacancy judging circuit 6 that the signal is in use, the process returns to step A again and the setting operation of another communication channel is carried out. .

In step C, the frequency is 2 × AC
When it is determined that the channel of is an empty channel,
Next, a determination operation is performed as to whether or not a channel having a frequency of (A + C) / 2 is vacant (step D). Such an operation is performed by the channel switching operation of the channel designation circuit 5 under the control of the control circuit 4 as described above.
When such a switching operation is performed, the receiving circuit 3 receives the frequency (A +
C) ÷ 2 signal is received. The receiving circuit 3
When the operation of detecting the carrier level of the received signal is performed and it is determined by the availability determination circuit 6 that the signal is in use, the process returns to step A again, and the operation of setting another communication channel is performed.

In step D, the frequency is (A + C)
When it is determined that the channel of ÷ 2 is an empty channel, it is determined that the channel of frequency A set in step A can be used as a communication channel, and the number information of the channel is stored in the channel memory circuit 7. (Step E).

The call channel setting operation is performed as described above, but the channel frequency A and frequency 2 × A− stored in the channel memory circuit 7 in this manner are set.
The C and frequency (A + C) / 2 channels may be used after being stored in the channel memory circuit 7 by another wireless telephone. Therefore, the operation described above is
After the channel memory circuit 7 stores the number information of callable channels, it is performed every predetermined time.

As described above, the call channel setting operation based on the flow chart shown in FIG. 1 is performed. Next, description will be given based on the flow chart shown in FIG. Figure 2
In the above, since the steps A and B are the same as the operation of FIG. 1, the description thereof will be omitted.

When it is determined in step B that the channel of frequency A is an empty channel, the control circuit 4 next determines whether or not there is a channel of frequency 2 × A-C (step F). . When it is determined that there is a channel, the operation of determining whether or not the channel having a frequency of 2 × AC is vacant is performed as in the operation of FIG. 1 (step C). Then, if that channel is in use, the process returns to step A and the setting operation of another communication channel is performed.

When it is determined in step F that there is no channel of frequency 2 × A-C and when it is determined in step C that the channel of frequency 2 × AC is empty,
Next, the control circuit 4 determines whether or not there is a channel whose frequency is (A + C) / 2 (step G). When it is determined that there is a channel, the frequency is (A
A determination operation is performed as to whether or not the + C) / 2 channel is vacant. (Step D). Then, if that channel is in use, the process returns to step A and the setting operation of another communication channel is performed.

When it is determined in step G that there is no channel of frequency (A + C) / 2, and when it is determined in step D that the channel of frequency (A + C) / 2 is empty, the setting is made in step A. It is determined that the channel of frequency A can be used as a communication channel, and the number information of the channel is stored in the channel memory circuit 7 (step E).

In steps F and G, the channel whose frequency is 2 × AC and the frequency whose frequency is (A +
If it is judged that there is no channel of C) ÷ 2, it is not judged whether or not the channel is vacant, so that it is not necessary to perform an unnecessary switching operation of the reception frequency of the receiving circuit 3, and the operation of setting the communication channel is performed. Can be done promptly.

In the above description, the case where one control channel is used for a short time at the start of a call has been described.
When there are two control channels, the number of channels for determining whether or not there are free channels increases.
That is, when the frequencies of the two control channels are B and C, the frequency A of the communication channel, frequency 2 × A−B, frequency (A + B) / 2, frequency 2 × A−C and frequency (A
It is determined whether or not the + C) / 2 channel is vacant.

[0019]

According to the present invention, when the frequency of the channel for communication is A and the frequency of the control channel used only at the start of communication is C, not only the frequency A and the frequency 2 × A-C channel but also the frequency ( A + C) ÷ 2 not only is it determined whether or not the channel of frequency 2 × A-C is used, but it is determined whether or not the channel of frequency 2 × A-C is used. Since the call channel is set without making the above judgment, that is, the call channel is set without performing unnecessary judgment operation, the call channel can be set quickly. Further, the present invention is directed to the frequency A,
Not only is it determined whether the frequency 2 × A−C and frequency (A + C) / 2 channels are used, but if there is no frequency (A + C) / 2 channel,
Since the call channel is set without judging whether or not the frequency (A + C) / 2 channel is used, that is, the call channel is set without performing unnecessary judgment operation. The call channel can be set quickly.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining a call channel setting method according to the present invention.

FIG. 2 is a flowchart showing an embodiment of a call channel setting method of the present invention.

FIG. 3 is a block diagram of a circuit incorporated in a base unit of a wireless telephone to which the call channel setting method of the present invention is applied.

[Explanation of symbols]

 2 transmitter circuit 3 receiver circuit 4 control circuit 5 channel designation circuit 6 vacancy judgment circuit

Claims (2)

(57) [Claims] 1. A mobile phone comprising a base unit connected to a telephone line and a handset that communicates wirelessly with each other, and when a call is started, a call channel is selected by selecting an unused call channel of another wireless telephone. In the configured wireless telephone, when the frequency of the channel for communication is A and the frequency of the control channel used only at the start of communication is C, the frequency A, the frequency 2 × A−C, and the frequency (A + C) / 2 channel Frequency is determined by determining whether or not
If there is no A-C channel, the frequency is 2 x A
A call channel setting method for a wireless telephone, wherein the call channel is set without determining whether or not the channel C is used. 2. The mobile phone comprises a base unit connected to a telephone line and a handset unit that communicates wirelessly with each other, and when a call is started, a call channel is selected by selecting an unused call channel of another wireless telephone. In the configured wireless telephone, when the frequency of the channel for communication is A and the frequency of the control channel used only at the start of communication is C, the frequency A, the frequency 2 × A−C, and the frequency (A + C) / 2 channel Is used and the frequency (A
+ C) ÷ 2 channel does not exist, the call of the wireless telephone is characterized in that the call channel is set without judging whether or not the frequency (A + C) ÷ 2 channel is used. Channel setting method.