JP3138389B2 - Digital cordless telephone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital cordless telephone capable of making a direct wireless connection between a parent device and a child device and between a child device and a child device.

[0002]

2. Description of the Related Art Conventionally, a digital cordless telephone has a base station (PS) connected to an exchange via a telephone line,
It comprises a plurality of wireless slaves (CS), and as a wireless transmission and reception system between the master and the slaves, a TDMA / TDD system (Time
Division Multipie Access / Time Division Duplex)
For such a digital cordless telephone, a standard has been established at the Radio System Development Center, and the final draft is "RCR STD-2".
8 "has been approved. And this standard "RCR
TDMA / TDD defined by "STD-28"
In the system, one frame is composed of a plurality of transmission slots and the same number of reception slots, and each transmission slot is associated with a reception slot, and transmission / reception is performed by a combination of the transmission slot and the reception slot. That is, since transmission and reception are performed in a transmission slot and a reception slot with time separation, the transmission frequency and the reception frequency can be the same frequency, and a plurality of transmissions and receptions can be performed at one frequency. .

[0003] In such a digital cordless telephone, a wireless connection can be established between the master unit and the slave unit and between the slave unit and the slave unit at a single frequency. Is provided only within the reach of the user, and an extension call function that allows a user to make a call directly by wireless connection using this single frequency.

[0004]

However, in the above-mentioned conventional digital cordless telephone, both radio waves need to reach to make a wireless connection at a single frequency. The connection could not be made. Therefore, when making an extension call by using the extension call function, the communication range of the extension call is the range that the radio waves of both parties making the extension call can reach, and the range between the master unit and the slave unit and the slave unit beyond that range There was a problem that extension calls could not be made between the two.

It is an object of the present invention to provide a digital cordless telephone capable of making a wireless connection between a master unit and a slave unit and between slave units even when radio waves do not reach each other.

[0006]

In order to achieve the above object, an invention according to claim 1 comprises a master unit and a plurality of slave units, and performs a call by making transmission and reception different in time. In a digital cordless telephone capable of making a direct call between the parent device and the child device and between the child devices, after transmitting a call signal for calling the callee, when there is no response from the callee, Calling means for making a call-side call request to another station in the communication area; and upon receiving the above-mentioned call-side call request, transmitting a call-in signal for calling the call-side, thereby making the call-side and call-side while Ru is provided a relay device for relaying and said relay means, wear
A provisional response signal transmitted from the called party in response to the transmission of the call signal
A temporary radio field intensity detecting means for detecting the radio field intensity of the signal,
Detection of transmitting a detection signal to the calling side by the wave intensity detection means
Signal transmitting means, wherein the incoming call means includes the detection signal
Radio wave for detecting the radio field intensity of the detection signal in accordance with the reception of
Strength detection means and the radio wave strength detection means
Based on the received radio wave intensity and the radio wave intensity based on the detection signal.
And another station selecting means for selecting another station to be used for relay.
The configuration is as follows.

[0007] The invention according to claim 2 is the invention according to claim 1.
In addition to the configuration of
Based on the radio wave intensity detected by the
Other than those that have almost the same signal strength
It is configured to be selected as a station .

[0008] The invention according to claim 3 provides the invention according to claim 2.
In addition to the configuration of
Based on the radio wave intensity detected by the
When there is more than one that have almost the same
With other stations that use the strongest signal for relaying
And then select it .

According to a fourth aspect of the present invention, a master unit and a plurality of slave units are provided.
And make calls differently in time between sending and receiving.
And make a direct call between the parent device and the child device and between the child devices.
Digital cordless telephones
After transmitting the incoming call signal that calls the called party, the called party responds.
When there is no answer, the called party calls another station within the communication range.
Calling means for making a request; and
Sends a call signal to call the called party, and calls the calling party.
And relay means for relaying to the
Configuration in which the stage determines whether or not to perform relaying based on the remaining battery level
It is obtained by the.

According to a fifth aspect of the present invention, a master unit and a plurality of slave units are provided.
And make calls differently in time between sending and receiving.
And make a direct call between the parent device and the child device and between the child devices.
Digital cordless telephones
After transmitting the incoming call signal that calls the called party, the called party responds.
When there is no answer, the called party calls another station within the communication range.
Calling means for making a request; and
Sends a call signal to call the called party, and calls the calling party.
And relay means for relaying to the
Configuration in which the stage determines whether or not to perform relaying based on the state of charge
It is obtained by the.

[0011]

Therefore, according to the invention described in any one of claims 1乃 optimum claim 3, in order to perform wireless connection between and between handset of the master unit and the slave unit, the master unit or slave unit In the case where the calling side calls the slave unit or the master unit as the called side, and when there is no response from the called side to the called signal transmitted from the calling side, the called means is called. The side determines that the terminal is not in the communication area of the calling side, and issues a called side call request to the other station in the communication area to call the called side. Then, when the other station within the communication range of the calling side receives the called side calling request, the relay means transmits a called signal for calling the called side and relays between the calling side and the called side. Thus, a wireless connection between the calling side and the called side can be established.

In addition, after the relay means transmits an incoming call signal for calling the called side, when the temporary response signal is transmitted from the called side in response to the incoming call signal, the temporary radio wave intensity detecting means receives the signal. The radio wave intensity of the provisional response signal is detected, and the detection signal transmission means transmits the detection signal to the calling side. Then, when the detection signal is received on the calling side, the radio field intensity detection means detects the radio field intensity of the received detection signal, and the other station selection means detects the radio field intensity based on the radio field intensity detected by the radio field intensity detection means and the detection signal. by selecting other stations using the relay based on the radio field intensity can be selected as appropriate as the relay station when the relay station being in communication range of both the calling and the called party have multiple .

According to the fourth or fifth aspect of the present invention , a wireless connection is established between the master unit and the slave unit and between the slave units.
In addition, the handset or the slave that is the called
Is used to call the parent device and is sent from the calling party
When there is no response from the called party to the incoming call signal, the called party
The stage determines that the called party is not within the communication range of the calling party and communicates.
Incoming calls to other stations in the area to call the called party
Make a side call request. And, if you are within the communication range of the calling party,
When the station receives this called side call request, the relay means
Determine whether to relay based on the remaining battery level or charging status
Battery when the battery level is low or
In such a case, it can be prevented from being used as a relay station .

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of a slave unit in a digital cordless telephone according to an embodiment of the present invention. FIG. 2 is an explanatory diagram showing an example of an arrangement state of a base unit and a slave unit of the digital cordless telephone. 3 is a control sequence diagram showing a basic operation of the wireless connection in the relay operation, FIG. 4 is a control sequence diagram showing a wireless release operation in the relay operation, and FIG. 5 is a diagram showing the arrangement state of the master unit and the slave unit of the digital cordless telephone. FIG. 6 is a control sequence diagram showing a wireless connection operation including a relay station selecting operation in a relay operation, and FIG. 7 is a control showing a wireless connection operation including a relay station switching operation in a relay operation. It is a sequence diagram.

In FIG. 1, reference numeral 1 denotes an antenna for transmitting and receiving a control signal and an audio signal, and 2 denotes a π / 4 shift QPSK modulation signal which is switched to a reception system 2a at a set reception timing and is received by the antenna 1. Demodulation according to the transmission method and the transmission system 2b at the transmission timing.
The radio unit 3 modulates the input transmission data by the π / 4 shift QPSK modulation method and supplies the modulated data to the antenna 1, and the data expansion and decoding of the signal demodulated by the reception system 2 a of the radio unit 2 are performed. The signal processing section analyzes the signal type, compresses the input digital data, adds an additional signal, creates a signal having a predetermined frame configuration, and sends the signal to the transmission system 2b of the wireless section 2.

Reference numeral 4 denotes a memory for temporarily storing digital data subjected to signal processing by the reception system 3b of the signal processing unit 3, and reference numeral 5 denotes analog data of the digital data subjected to signal processing by the reception system 3b of the signal processing unit 3. A voice codec unit that decodes a signal and converts the input analog voice into digital data by sampling, a speaker 6 that emits a voice message decoded by the voice codec unit 5, and a voice 7 that converts the voice message into analog voice. This is a microphone input to the codec unit 5.

Reference numeral 8 denotes a secondary battery serving as a power supply of the apparatus, 9 denotes a power supply unit that supplies a voltage from the secondary battery 8 to each unit as a power supply,
Reference numeral 10 denotes a battery remaining amount detecting unit that detects the remaining battery amount of the secondary battery 8, and 11 denotes a charging detecting unit that detects whether the secondary battery 8 is being charged.

Numeral 12 is a numeric keypad used for inputting a telephone number.
An operation input unit 13 includes an external call button, an internal call button, and a relay function necessity switch.
This is a control unit that controls each unit based on an operation command from.

When the master unit and the slave unit of the digital cordless telephone configured as described above are arranged as shown in FIG. 2, the master unit A calls the slave unit B to perform an extension call between the master unit and the slave unit. The case of performing the operation will be described based on the control sequence shown in FIG.

In FIG. 2, a broken line a indicates a radio wave arrival range of the master unit A, a broken line b indicates a radio wave arrival range of the slave unit B, and a broken line c indicates a radio wave arrival range of the slave unit C. Machine C
Are located, the slave C is located within the dashed line b, and the master A and the slave B are located within the dashed line c. That is, master unit A
It is impossible for the slave unit B and the slave unit B to receive each other's radio waves, and the radio wave from the slave unit C can be received by both the master unit A and the slave unit B.

In such an arrangement of the master unit A and the slave units B and C, when the extension button of the operation input unit 12 of the master unit A is operated to request an extension call with the slave unit B, the control unit 13 The signal processing unit 3 is controlled based on the operation command, and 29 bits
42-bit calling identification code (CS-ID) composed of a system call code of
28 bits composed of 8 bits PS calling code
A call signal including a destination identification code (PS-ID) is generated in a predetermined signal format. The PS-ID included in the calling signal is ID information of the slave unit B.

Then, the calling signal generated by the control unit 13 and the signal processing unit 3 is sent to the transmission system 2b of the radio unit 2, and the transmission system 2b of the radio unit 2 transmits the call signal based on the control from the control unit 13. The incoming message created in 3 is transmitted to the antenna 1 at a predetermined transmission timing and transmitted from the antenna 1 to the slave unit B (a1).

When the incoming call message from the main unit A is received by the slave unit B by the receiving system 2a of the antenna 1 and the radio unit 2, the receiving system 3a of the signal processing unit 3 performs predetermined signal processing and receives the incoming message. It is determined that the call is a call message, and the control unit 13 determines that the call is to the own station based on the calling identification code (CS-ID) and the called identification code (PS-ID) included in the received message. And this CS-
Using the ID, the transmission system 3b of the signal processing unit 3 creates a link CH establishment request message including a destination identification code (CS-ID) and a calling identification code (PS-ID) in a predetermined signal format. The signal is transmitted to the parent device A at a predetermined timing by the transmission system 2b and the antenna 1 of the second device.

However, as shown in FIG. 2, an incoming message from master unit A cannot be received by slave unit B from the radio wave coverage between master unit A and slave unit B in the present embodiment, and link CH An establishment request message or the like is not transmitted to master unit A.

On the other hand, the slave C located within the radio wave arrival range of the master A
Then, the incoming call message transmitted to the slave unit B is received. When the incoming call message transmitted from the master unit A to the slave unit B in the slave unit C is received by the reception system 2a of the antenna 1 and the radio unit 2, the reception system 3a of the signal processing unit 3 of the slave unit C Predetermined signal processing is performed, the message is determined to be an incoming call message, and the control unit 13 calls the slave unit B from the slave unit B based on the CS-ID and the PS-ID included in the incoming call message. It is determined that the call is not a call to a station, and the receiving system 3a of the signal processing unit 3 is determined.
The incoming call message subjected to the signal processing is temporarily stored in the memory 4. If the control unit 13 determines that the base unit A is calling the slave unit B instead of calling the own unit, the slave unit C informs that the own station is within the communication range of the master unit A. Then, a link CH establishment request message for requesting the designation of a communication carrier is transmitted to the master unit A (a2). Note that this link CH establishment request message includes the CS-ID as the destination identification code and the PS-ID of the slave C as the calling identification code.

Then, when master unit A receives a link CH establishment request message from slave unit C while transmitting an incoming call message to slave unit B, master unit A transmits the link CH establishment request message. Does not transmit a link CH assignment message to the mobile station, and the control unit 13 communicates with the local station based on the CS-ID and the PS-ID included in the link CH establishment request message within the radio wave range of the local station. It is determined that it is possible, and it is set that it can be used as a relay station.

[0027] Then, in a state where master unit A is transmitting an incoming call message to slave unit B, and master unit A is set as slave unit C as a relay station, the PS-address included in the incoming call message is set. When a link CH establishment request message or the like from the slave unit B corresponding to the ID is not received even after waiting for a predetermined time,
The control unit 13 determines that the slave unit B is not within the radio wave range of the own station, and transmits a proxy call request message to the slave unit C so as to call the slave unit B (a3).

When the proxy call request message from the master unit A is received by the slave unit C, the control unit 13
The incoming call message temporarily stored is read out, and the read out incoming message is subjected to a predetermined signal processing in the transmission system 3b of the signal processing unit 3 to have a predetermined signal format. At the transmission timing (a4).

Since the slave B is within the radio wave arrival range of the slave C, the incoming call message from the slave C is received. Then, in the slave unit B, when the incoming call message is received, the control unit 13 causes the calling identification code (CS-ID) and the incoming call identification code (PS-I) included in the incoming call message.
D), it is determined that the call is to the own station.
Using the S-ID, the transmission system 3b of the signal processing unit 3 creates a link CH establishment request message in a predetermined signal format, and transmits the message at a predetermined transmission timing based on the control of the control unit 13 (a5).

When the handset C receives the link CH establishment request message from the handset B, the receiving system 3a of the signal processing unit 3 performs predetermined signal processing and determines that the message is a link CH establishment request message. Then, the control unit 13 determines that the slave unit B is within the radio wave range of the own station, and temporarily stores the link CH establishment request message processed by the reception system 3a of the signal processing unit 3 in the memory 4. Then, the link CH establishment request message temporarily stored in the memory 4 is read at a timing determined by the control unit 13, and the read link CH establishment request message is subjected to predetermined signal processing in the transmission system 3 b of the signal processing unit 3. The control unit 1 has a predetermined signal format.
Transmission is performed at a predetermined transmission timing based on the control of No. 3 (a6).

When the master unit A receives the link CH establishment request message from the slave unit C, the receiving system 3a of the signal processing unit 3 performs predetermined signal processing, and determines that the message is the link CH establishment request message. The control unit 13 selects a slot having two or more usable slots on a single carrier confirmed in accordance with a predetermined carrier sense condition on a single frequency, and selects two available slots in the selected communication carrier. Master unit A-child unit C
Between the slave unit B and the slave unit C, and controls the transmission system 3b of the signal processing unit 3 and the transmission system 2b of the wireless unit 2 to transmit a link CH assignment message from the antenna 1 (a7).

When the slave unit C receives the link CH assignment message from the master unit A, a predetermined signal processing is performed by the reception system 3a of the signal processing unit 3, and the control unit 13
, The physical channel (slot and frequency) used with the base unit A is checked, and the physical channel used with the handset B is checked, and this link CH assignment message is temporarily stored in the memory 4. . Then, the link CH assignment message temporarily stored in the memory 4 is read out and transmitted at the timing determined by the control unit 13 (a8), and a synchronization burst is transmitted based on the physical channel confirmed by the control unit 13 to synchronize. Establishment is performed (a9).

When the slave unit B receives the link CH assignment message from the slave unit C, a predetermined signal processing is performed by the receiving system 3a of the signal processing unit 3, and the control unit 13
Then, a physical channel to be used with the slave unit C is confirmed, and a synchronization burst is transmitted to establish synchronization (a9).

Next, the master unit A sends a SABM (Set Asynchro
nous Balanced Mode) (a10), and this SAB
The slave C that has received M transmits the SABM to the slave B (a11). When the slaves B and C receive the SABM, the UA corresponding to the SABM is received.
(Unnumbered Acknowledgment) is returned to each (a
12).

Then, after returning UA in the slave unit B,
The control unit 13 of the slave unit B determines that the link CH has been established,
The transmission system 3b of the signal processing unit 3 and the transmission system 2b of the radio unit 2 are controlled to transmit an incoming call response message from the antenna 1 (a13). When the incoming call response message from the handset B is received by the handset C, the incoming call response message is temporarily stored in the memory 4 and temporarily stored in the memory 4 at a timing determined by the control unit 13. The received call response message is read and transmitted (a14). And
When the incoming call response message from handset C is received at base unit A, transmission and reception of a predetermined message for setting various functions to be used for a call between base unit A and handset B are thereafter performed in the same manner as the child. This is performed by relaying the device C.

After the various functions are set between the master unit A and the slave unit B, a ringer (not shown) is sounded at the slave unit B to notify the user of the slave unit B of a call. At the same time, the control unit 13 controls the transmission system 3b of the signal processing unit 3 and the transmission system 2b of the wireless unit 2 to transmit a call message (a15). When the call message from handset B is received at handset C, the call message is temporarily stored in memory 4 and the call message temporarily stored in memory 4 at the timing determined by control unit 13 is stored. Read and transmit (a16).

When the user performs an on-hook operation using the operation input unit 12 in response to a call notification by ringing of the ringer or the like of the slave unit B, the control unit 13 performs signal processing based on the on-hook operation by the operation input unit 12. Transmission system 3b of unit 3
Then, it controls the transmission system 2b of the radio unit 2 to transmit a response message (a17). When the response message from the child device B is received by the child device C, the response message is temporarily stored in the memory 4, and the response message temporarily stored in the memory 4 at the timing determined by the control unit 13 is received. Read and transmit (a18).

When the response message from the child device C is received by the parent device A, the control unit 13 responds to the received response message by the transmission unit 3b of the signal processing unit 3.
Then, it controls the transmission system 2b of the radio unit 2 to transmit a response confirmation message (a19). When the slave unit C receives the response confirmation message from the master unit A, the response confirmation message is temporarily stored in the memory 4 and the control unit 1
3 reads out and transmits the response confirmation message temporarily stored in the memory 4 at the timing determined by (3)
0).

Next, the master unit A sends a DISC (Disconnect)
Is transmitted (a21), and the slave C that has received this DISC transmits this DISC to the slave B (a22). When the slaves B and C receive the DISC, UAs are returned to the respective slaves (a
23), the communication between the parent device A and the child device C and the communication between the child device B and the child device C are in progress, and therefore, the communication between the parent device A and the child device B is being made with the child device C as a relay station. In such a communication state, the audio data from the master unit A is transmitted via the physical channel between the master unit A and the slave unit C in the same manner as in the above-described connection control of the communication channel. Is transmitted by the physical channel between the slave C and the slave B stored in the memory 4 of the slave A, so that the audio data from the master A is
And is emitted by the speaker 6. The audio data from the slave unit B is also transmitted to the master unit A via the slave unit C in the same manner as described above.
Is transmitted to

Therefore, even when the slave unit B is not in the radio wave arrival range of the master unit A, the slave unit C is used as a relay station and the master unit A-
An extension call can be made between the slave units B, and the voice data and the control message are transmitted at different slot timings via the slave unit C, so that the slave units C are relayed without causing radio interference with each other. As a station, a call can be made between the master unit A and the slave unit B.

Next, the operation of terminating the extension call between the master unit A and the slave unit B using the slave unit C as a relay station as described above will be described with reference to the control sequence shown in FIG.

For example, when a call end operation is performed by the operation input unit 12 in the base unit A, the control unit 13 transmits a disconnection message using the physical channel between the base unit A and the handset C based on the end operation. (B1), the slave unit C that has received the disconnection message temporarily stores the disconnection message in the memory 4, and transmits the stored disconnection message using the physical channel between the slave unit B and the slave unit C. (B2).

Then, when the disconnection message is received in the child device B and the child device C, the child device B uses the physical channel between the child device B and the child device C, and the child device C responds to the disconnection message. Using the physical channel between the parent device A and the child device C, a release message is returned to each (b3). When the parent device A and the child device C receive the release message, the parent device A responds to the release message. Using the physical channel between the parent device A and the child device C, the child device C
A release completion message is transmitted using the physical channel between the slave units C (b4).

Next, a DISC is transmitted from master unit A (b)
5), the slave C that has received the DISC transmits the DISC to the slave B (b6). When the slave B and the slave C receive the DISC, the slave UA returns a UA corresponding to the DISC (b7).

Then, a wireless CH disconnection message is transmitted from master unit A (b8), and slave unit C, which has received the wireless CH disconnection message, transmits the wireless CH disconnection to slave unit B (b9). Then, when the wireless device B and the wireless device C receive the wireless CH disconnection message, a wireless CH disconnection completion message is returned to each of them (b10) in response to the wireless CH disconnection message, and the communication ends and the device shifts to a standby state.

Next, based on the control sequence of FIG. 6, the control of selecting a relay station when there are a plurality of slave stations C which can be relay stations within the radio wave arrival range of the master station A as shown in FIG. 5 will be described. I do. A case will be described where there are four slave units C that can be relay stations in the radio wave arrival range of the master unit A, and the four slave units are defined as slave units C1, C2,
The child device C3 and the child device C4.

In such an arrangement of the master unit A and the slave units B and C, when an extension button of the operation input unit 12 of the master unit is operated to request an extension call with the slave unit B, the communication channel connection operation is performed. The incoming call message is transmitted in the same manner as (c1).
Then, the slave C that has received the incoming call message from the master A
1, C2, C3, and C4 each determine that the call is not a call to their own station, temporarily store the incoming call message in the memory 4, and link the master unit A with the link CH.
An establishment request message is transmitted (c2).

Then, in a state where the master unit A is transmitting the incoming call message to the slave unit B, each of the slave units C1, C2,.
When receiving a link CH request message from C3 and C4, the link CH
The assignment message is not transmitted, and the control unit 13 sets that the slave units C1, C2, C3, and C4 can be used as relay stations. Then, in a state where master unit A transmits an incoming message to slave unit B, and master unit A has set a plurality of slave units C1, C2, C3 and C4 as relay stations, the master unit A transmits the incoming call message to the slave unit B. When a link CH establishment request message or the like is not received from the corresponding slave unit B even after waiting for a predetermined time, the control unit 13 determines that the slave unit B is not within the radio wave range of the own station, and performs a proxy call for calling the slave unit B. A request message is transmitted to each of the slave units C1 to C4 at different timings (c3).

When each of the slave units C1, C2, C3 and C4 receives the proxy call request message from the master unit A at an individual timing, the slave unit temporarily stores the message in the memory 4 on the basis of the individually received timing. Are transmitted at different timings (c4). When the slave unit B receives the incoming messages from the slave units C1 to C4 at different timings, the slave unit B transmits the link CH establishment request messages at different timings based on the received timings (c5). . At this time, the incoming call message from the handset C3 is not received by the handset B, so that no link CH establishment request message is transmitted to the handset B.

When each of the slave units C1, C2, and C4 receives a link CH establishment request message from the slave unit B at an individual timing, the reception system 2 of the radio unit 2
a, the radio wave intensity when the link CH establishment request message is received is measured, and the provisional response notification message including the measured radio wave intensity information is transmitted at different timings based on the timing at which the link CH establishment request message is received. Transmit (c6).

When the master unit A receives the temporary response notification messages from the slave units C1, C2 and C4 at individual timings, the receiving system 2a of the radio unit 2 receives the temporary response notification message. Each of the radio wave intensities is measured and sent to the control unit 13 and the control unit 13
In step (3), the radio wave intensity information included in the provisional response notification message is read, and the radio wave intensity information included in the provisional response notification message and the information on the radio wave intensity when the provisional response notification message is received are stored in a corresponding manner. And the slave units C1, C
When the provisional response notification message is received for 2 and C4, the radio field intensity information is stored, and after a predetermined time has elapsed, the provisional response notification message from the handset C3 is not received.
It is determined that the slave B is not in the radio wave arrival range of the slave C3, and which of the slaves C1, C2, and C4 is to be used as a relay station is determined.

The determination of the relay station is made based on the radio wave intensity information stored for the slave units C1, C2 and C4, respectively, and the slave units C1, C2 and C4 establish the link CH from the slave unit B. The radio wave intensity at the time of receiving the message and the slaves C1, C2 and C
4 and the reception strength when the provisional response notification message is received is substantially equal, and when there are a plurality of similar reception strengths, the one having the highest radio wave strength is selected. By the selection rule based on such radio wave intensity information, the slave C2 which is considered to be located exactly between the master A and the slave B.
Will be selected as a relay station.

When the parent device A selects the use of the child device C2 as a relay station, the same operation as the above-described communication channel connection control is performed, and processing such as link CH assignment (c7, c8) is performed. Communication is in progress.

Accordingly, even when there is no slave unit B in the radio wave arrival range of master unit A and there are a plurality of slave units that can be used as relay stations, the slave unit most suitable for use as a relay station is used. A mobile phone can be selected, and an extension call can be made between the base phone A and the handset B using the selected handset as a relay station.

Next, there is no slave unit B in the radio wave arrival range of master unit A, and slave units C1 and C that can be used as relay stations.
2 is in the radio wave range of the main unit A,
In the case where an extension call is performed between the master unit A and the slave unit B using the base station 1 as a relay station, the slave unit C1 relays the relay between the master unit A and the slave unit B due to a shortage of battery capacity or deterioration of radio wave intensity. The call connection switching control when the communication cannot be performed will be described based on the control sequence of FIG.

During communication between master unit A and slave unit B using slave unit C1 as a relay station, slave unit C1 cannot perform relay between master unit A and slave unit B due to insufficient battery capacity or deterioration of radio wave intensity. When it is determined that the slaves C1 and B
(D1, d2).

When the master A receives the relay stop notification message from the slave C1, an incoming call signal for calling the slave B is transmitted at a timing different from the timing used for communication with the slave C1 ( d3). Further, when the slave unit B receives the relay stop notification message from the slave unit C1, the slave unit B enters the call waiting state while performing communication while maintaining synchronization with the slave unit C1.

On the other hand, when the slave unit C2 receives the incoming call message from the master unit A, it determines that the incoming call message is not a call to its own station, and temporarily stores the incoming call message in the memory 4. And, a link CH establishment request message is transmitted to the master unit A (d4).

When receiving a link CH request message from each of the slave units C2 while the master unit A is transmitting an incoming call message to the slave unit B, a link CH is allocated to the link establishment request message. The message is not transmitted, and the control unit 13 sets that the slave unit C2 can be used as a relay station. Then, base unit A transmits an incoming call message to slave unit B, and base unit A
In a state where the slave unit C2 is set as a relay station, if a link CH establishment request message or the like is not received from the slave unit B corresponding to the incoming call message even after waiting for a predetermined time, the control unit 13 determines that the slave unit B It is determined that the mobile station is not in the radio wave arrival range, and a proxy call request message for calling the mobile station B is transmitted to the mobile station C2 (d5).

When the handset C2 receives the proxy call request message from the master A, it reads out the incoming call message temporarily stored in the memory 4 and transmits it at a predetermined timing (d6). Then, in the slave unit B, the slave unit C
When receiving the incoming message from the communication device 2, a link CH establishment request message is transmitted at a predetermined timing (d 7).
The child device C2 relays the link CH establishment request message from the child device B (d8), and is received by the parent device A.

In response to the link CH establishment request message from slave unit C2, master unit A selects a communication carrier having two or more available slots on a single frequency confirmed in accordance with a predetermined carrier sense condition. The two usable slots in the selected communication carrier are designated between the parent device A and the child device C and between the child device B and the child device C2, and transmitted as a link CH assignment message (d9).

When the slave C2 receives the link CH assignment message from the master A, the slave C2 receives the link CH assignment message from the master C and the slave C based on the received link CH assignment message.
-Confirm the physical channel used between the slave units C and temporarily store the link CH assignment message in the memory 4 and transmit it at a predetermined timing (d10). Then, the slave C2 and the slave B transmit a synchronization burst on a physical channel based on the link CH assignment message received, and establish synchronization (d11).
At this time, a synchronization burst is also transmitted from the slave unit C1 at a predetermined timing. However, since the master unit A transmits a synchronization burst on a physical channel different from the last time in response to the link CH establishment request message, Slave unit C1
No synchronization is established in the physical channel between the master unit A and the slave unit C1 due to the synchronization burst from.

Next, SABM is transmitted from master unit A (d1
2) Then, the slave C2 that has received the SABM transmits the SABM to the slave B (d13). When the slave B and the slave C2 receive the SABM, the SBM is received.
The UA is returned to each corresponding to the ABM (d14).

Then, after returning UA in the slave unit B,
When it is determined that the link CH has been established, an incoming call response message is transmitted at a predetermined timing (d15), and the child device C2
In step, the call response message from the slave unit B is temporarily stored in the memory 4, read out at a predetermined timing, and transmitted to the master unit A (d16). Slave unit C2 in master unit A
When the call response message from the slave unit B relayed by the slave unit B is received, the transmission and reception of a predetermined message for setting various functions to be used for a call between the master unit A and the slave unit B are thereafter performed in the same manner as the slave unit. This is performed by relaying the device C2.

When various functions used for a call between the master unit A and the slave unit B are set, the master unit A
(D17), and the slave C2 receiving this DISC
Transmits the DISC to the slave unit B (d18).
When the slave B and the slave C2 receive the DISC, the slave UA returns a UA corresponding to the DISC (d19).

When the master unit A receives the UA, a response message is transmitted at a predetermined timing (d20), and the slave unit C2 stores the response message from the master unit A in the memory 4.
Is temporarily stored, read out at a predetermined timing, and transmitted to the slave unit B (d21), so that communication between the master unit A and the slave unit C2 and between the slave unit B and the slave unit C2 are in communication, and accordingly, the slave unit With C2 as a relay station, communication is established between master unit A and slave unit B, and a call can be made.

Next, the operation control for determining whether or not to perform relay in a slave unit that can be used as a relay station will be described with reference to the flowchart of FIG. It is assumed that a slave unit used as a relay station is provided with a relay on / off button for switching whether or not to perform a relay operation and a setting button for setting a system limitation for performing a relay operation in the operation input unit 12. .

This flowchart is started when the main power of the slave unit is turned on, and the process proceeds to step F1. In step F1, the receiving system 2a and the receiving system 2b of the radio unit 2 are controlled to be kept in a standby state, and the process proceeds to step F2. In step F2, it is determined whether or not there is an incoming message sent from another station. If it is determined that there is no incoming message, the process proceeds to step F1 to repeat the above operation, and it is determined that there is an incoming message. If
Move to step F3.

In step F3, the calling identification code and the called identification code are read from the incoming call message in step F2, and the flow shifts to step F4. In step F4, the originator and the called party based on the calling identification code and the called identification code read in step F3. It is determined whether or not the original system is the own system. If it is determined that the system is the own system, the process proceeds to step F5. If it is determined that the system is not the own system, the process proceeds to step F6.

In step F5, it is determined whether or not the mode for performing the relay operation is set by the relay on / off button of the operation input unit 12, and if it is determined that the mode is for performing the relay operation, the process proceeds to step F7. If it is determined that the relay operation is to be performed, the flow chart is terminated, and if it is determined that the mode is such that the relay operation is not performed, the process proceeds to step F8, where it is determined that the relay operation is not performed, and The flowchart ends.

On the other hand, if it is determined in step F4 that the system is not the own system and the process proceeds to step F6, it is determined in step F6 whether a mode in which the relay operation is performed by the relay on / off button of the operation input unit 12 is set. If the mode is determined to be the mode for performing the relay operation, the process proceeds to step F9. If the mode is determined not to be the mode for performing the relay operation, the process proceeds to step F8 and it is determined that the relay operation is not performed. Then, this flowchart ends.

In step F9, it is determined by the setting button of the operation input unit 12 whether or not the mode is for relaying only the own system. If it is determined that the mode is for relaying only the own system, the process proceeds to step F8. Then, if it is determined that the relay operation is not to be performed, the flow chart is ended. If it is determined that the mode is not the mode in which only the own system is relayed, the process proceeds to step F7 to perform the relay operation. Judgment is made and this flowchart ends.

If it is determined in step F7 that the relay operation is to be performed, the relay operation is controlled after the end of this flowchart. If it is determined in step F8 that the relay operation is not to be performed, the process waits after the end of the flowchart. Move to the receiving state.

Accordingly, it is possible to determine whether or not to perform relaying by using the relay on / off button and the setting button of the operation input unit 12, and it is possible to cope with a case where the relay station is not desired to be used. .

Next, the operation control for determining whether or not to perform relaying in a slave unit that can be used as a relay station based on the remaining battery level will be described with reference to the flowchart of FIG.

This flowchart is started when the main power of the slave unit is turned on, and the flow shifts to step F21. In step F21, the receiving system 2a and the receiving system 2b of the radio unit 2 are controlled to be kept in a standby state, and
Move to 2. In step F22, it is determined whether or not there is an incoming call message transmitted from another station. If it is determined that there is no incoming message, the process proceeds to step F21 to repeat the above operation, and it is determined that there is an incoming call message. If so, the process proceeds to Step F23.

In step F23, the charging detector 11 determines whether or not the secondary battery 8 is being charged. If it is determined that the secondary battery 8 is being charged, the process proceeds to step F24 where it is determined that the relay operation is to be performed. When the lever flowchart ends and it is determined that charging is not being performed, the process proceeds to step F25.

In step F25, the battery remaining amount of the secondary battery 8 is measured by the battery remaining amount detecting section 10, and the process proceeds to step F2.
Then, in step F26, it is determined whether the remaining battery level measured in step F25 is equal to or more than a predetermined value and is sufficient.
If it is determined that there is sufficient power, the process proceeds to step F24, where it is determined that the relay operation is to be performed, and the flow chart is terminated.
Then, it is determined that the relay operation is not performed, and the flowchart ends.

When it is determined in step F24 that the relay operation is to be performed, the relay operation is controlled after the end of this flowchart. When it is determined in step F26 that the relay operation is not to be performed, the standby is performed after the end of this flowchart. Move to the receiving state.

Therefore, it is possible to determine whether or not to perform the relay based on the state of charge of the secondary battery 8 and the remaining amount of the battery.
When the remaining battery level is low, the relay station is not used as a relay station, so that it can be operated as a relay station only when the communication of the user of the slave unit used as the relay station is not affected.

In the present embodiment, a case has been described in which an extension call is made between a master unit and a slave unit and the relay station is a slave unit, assuming that wireless connection is performed using the relay station. The direct call between the slave units may be used, and the relay station may be the master unit or the slave unit. In this direct call between the slave units, no dedicated control carrier is provided, and the transmitting side is the communication carrier. A system in which an outgoing slot is detected and a call is made, and the receiving side scans all channels. Therefore, when a calling signal is transmitted on the transmitting side, there are two or more empty slots on a single frequency in advance. Or when a proxy call request is made, select a slot having two or more empty slots on a single frequency, and use a frequency received at the relay station receiving the proxy call request and a different transmission timing. Empty slot It may be to send a call signal with bets. Also, it is not limited to extension calls,
For example, a case may be used in which a base unit calls a slave unit in response to an incoming signal coming from a telephone line.

[0082]

As it is evident from the foregoing description, according to claim 1乃 optimum claim 3
According to the invention described in any of the above, when there is no response from the called side to the incoming call signal transmitted from the calling side, it is determined that the called side is not within the communication range of the calling side and the communication range is determined. Call request to the called station to the called station to the called station, and the called station calling the called party when the called station call request is received by the called station at the calling station. By transmitting a signal and relaying between the calling side and the called side, a wireless connection can be established between the calling side and the called side, so that the calling side and the called side which are not within the communication range of the calling side can be connected. Wireless connection and can make a call.

[0083] Furthermore, after transmitting the incoming call signal for calling the called party, when the provisional response signal from the called side in response is transmitted to the incoming call signal, detects the radio wave strength of the temporary response signal The signal is transmitted to the calling side as a detection signal, and the calling side detects the radio wave intensity when this detection signal is received, and based on the radio wave strength and the radio wave strength included in the detection signal, determines the other station used for relaying. by selecting, it is possible to relay station being in communication range of both the calling and the called party is selected as a relay station for appropriate when there are a plurality, originating
There are multiple relay stations within the communication range of both the calling side and the called side
Even in such a case, a good call can be made.

According to the invention set forth in claim 4 or claim 5, the incoming call signal transmitted from the calling side is transmitted from the incoming side to the incoming side.
Callee is not within range of caller when there is no response
And calls the called party to another station within the communication range.
Make a call to the called party to make it
When the other station receives this call request,
Judgment as to whether or not to relay based on the remaining battery level or charging status
As a result, when the battery level is low or the battery is exhausted
In that case, it can be prevented from being used as a relay station.
To operate the slave unit as a relay station.
Thus, it is possible to prevent the communication of the user of the slave unit from being affected .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a slave unit of a digital cordless telephone according to one embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an arrangement state of a master unit and a slave unit of the digital cordless telephone.

FIG. 3 is a control sequence diagram showing a relay operation in the digital cordless telephone.

FIG. 4 is a control sequence diagram showing a relay operation in the digital cordless telephone.

FIG. 5 is an explanatory diagram showing an arrangement state of a master unit and a slave unit of the digital cordless telephone.

FIG. 6 is a control sequence diagram showing a relay operation in the digital cordless telephone.

FIG. 7 is a control sequence diagram showing a relay operation in the digital cordless telephone.

FIG. 8 is a flowchart showing operation control of relay determination in the digital cordless telephone.

FIG. 9 is a flowchart showing operation control of relay determination in the digital cordless telephone.

[Brief description of reference numerals]

 DESCRIPTION OF SYMBOLS 1 Antenna 2 Radio part 3 Signal processing part 4 Memory 5 Audio codec part 6 Speaker 7 Microphone 8 Secondary battery 9 Power supply part 10 Battery remaining amount detecting part 11 Charging detecting part 12 Operation input part 13 Control part

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04Q ^7/ 00-7/38

Claims (5)

(57) [Claims] 1. A communication system comprising a master unit and a plurality of slave units, making a call with transmission and reception being different in time, and making a direct call between the master unit and the slave unit and between the slave units. Calling means for making a called call request to another station in the communication area when there is no response from the called side after transmitting a called signal for calling the called side, when receiving the incoming call side calls the request, while the Ru provided a relay means for relaying the calling side and the called side transmits a call signal for calling the called party, the relay means, incoming call Callee responds to signal transmission
Provisional radio field intensity that detects the radio field strength of the transmitted temporary response signal
And transmitting a detection signal from the detection means and the provisional radio wave intensity detection means to the calling side.
Detection signal transmitting means, and the receiving means receives the detection signal and performs the detection.
A radio field intensity detecting means for detecting a radio field intensity of the signal; a radio field intensity detected by the radio field intensity detecting means ;
Used for relaying based on the signal strength based on the detection signal
A digital cordless telephone comprising: another station selecting means for selecting another station . 2. The radio communication apparatus according to claim 2, wherein the other station selecting means detects the radio wave intensity.
Based on the radio wave intensity detected by the
Other stations that use relays that have almost the same signal strength as relays
2. The digital cordless telephone according to claim 1, wherein the digital cordless telephone is selected. 3. The other station selecting means, comprising:
Based on the radio wave intensity detected by the
When there are multiple items that have almost the same
With other stations that use the strongest signal for relaying
Digital cordless telephone according to claim 2, characterized in that selected. 4. A transmission and reception system comprising a master unit and a plurality of slave units.
Make a call with a different time from the call
Digital telephone that can make direct calls between
The cordless telephone sends a call signal that calls the called party, and then
When there is no response, the called station calls another station within the communication range.
Calling means for making an outgoing call request;
A middle joint that transmits a call signal and relays between the calling side and the called side
And the relaying means determines whether or not to perform relaying based on the remaining battery level.
Digital cordless telephone. 5. A transmitting and receiving apparatus comprising a master unit and a plurality of slave units.
Make a call with a different time from the call
Digital telephone that can make direct calls between
The cordless telephone sends a call signal that calls the called party, and then
When there is no response, the called station calls another station within the communication range.
Calling means for making an outgoing call request;
A middle joint that transmits a call signal and relays between the calling side and the called side
And the relaying means determines whether or not to perform relaying based on the state of charge.
Digital cordless telephone.