JP2002280933A - Communication station, communication changeover method and communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication system that uninterruptibly switches a channel for preventing data defects. SOLUTION: In the system, where communication stations 1, 2 can use a wired transmission channel 3 and a radio transmission channel 4 for mutual communication, when the channel is to be revised, the communication station 1 informs the communication station 2 of a medium (e.g. the transmission channel 3) which is new in use. As a result, after the new channel is set up, the communication station 1 informs the communication station 2 about a time, when the communication station 2 should interrupt the channel of a medium (e.g. the transmission channel 4) which has been used before. The communication station 2 interrupts the transmission channel 4 at the informed time. This time may be equal to the time the communication station 1 interrupts the transmission channel 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a communication station, a communication switching method, and a communication system that can use both a wired medium and a wireless medium.

[0002]

2. Description of the Related Art Some communication stations can communicate using both a wired medium and a wireless medium. According to this type of communication station, for example, in the event of a disaster or emergency,
It is possible to communicate using any suitable medium. FIG. 7 is a schematic diagram showing a communication system using this type of conventional communication station. In the figure, reference numerals 1 and 2 denote communication stations. The communication stations 1 and 2 are respectively located in buildings and the like. The communication stations 1 and 2 are connected to each other via a wired transmission path, and can communicate with each other via a wireless transmission path. The transmission path used is switchable.

FIG. 8 shows details of the conventional communication station shown in FIG.
8, reference numeral 11 denotes a data transmitting / receiving unit, 12 denotes a wired / wireless line switching unit, 13 denotes a wired synchronization establishing unit, 14 denotes a wireless synchronization establishing unit, 16 denotes a wired transmitting / receiving unit, and 17 denotes a wireless transmitting / receiving unit. The communication station 1 includes a data transmitting / receiving unit 11, a wired / wireless line switching unit 12, a wired synchronization establishing unit 13, a wireless synchronization establishing unit 14, a wired transmitting / receiving unit 16, and a wireless transmitting / receiving unit 17. 21 is a data transmitting / receiving unit, 22 is a wired / wireless line switching unit, 23 is a wired synchronization establishing unit, 24 is a wireless synchronization establishing unit, 26 is a wired transmitting / receiving unit, and 27 is a wireless transmitting / receiving unit.
The communication station 2 includes a data transmitting / receiving unit 21, a wired / wireless line switching unit 22, a wired synchronization establishing unit 23, a wireless synchronization establishing unit 24,
It includes a wired transmitting / receiving unit 26 and a wireless transmitting / receiving unit 27. Reference numeral 3 denotes a wired transmission path interconnecting the communication station 1 and the communication station 2,
Reference numeral 4 denotes a wireless transmission path interconnecting the communication station 1 and the communication station 2.

The data transmission / reception unit 11 separates and restores a data unit from the multiplexed data stream supplied from the external device to the communication station 1, and passes the restored data unit to the wired / wireless line switching unit 12. Further, the data transmission / reception unit 11 receives the data stream from either the transmission path 3 or 4 from the wired / wireless line switching unit 12, multiplexes the data units extracted from the data stream, and transfers the multiplexed data unit to the destination external device. The wired / wireless line switching unit 12 relays data exchanged between the data transmitting / receiving unit 11 and the communication station 2. The wired / wireless line switching unit 12 has a switching element therein, and receives a wired / wireless line input to the communication station 1.
The switching element is operated according to the wireless switching signal CO11, and switches the transmission path to be used to the wired transmission path 3 or the wireless transmission path 4. The wired synchronization establishing unit 13 has a function of establishing synchronization of a wired line with the communication station 2 of the other party. The wireless synchronization establishing unit 14 has a function of establishing synchronization of a wireless line with the communication station 2 of the other party. Wired transceiver 1
Reference numeral 6 has a function of enabling communication with the communication station 2 of the other party by a communication method corresponding to the wired transmission path 3. The wireless transmission / reception unit 17 has a function of enabling communication with the communication station 2 of the other party by a communication method corresponding to the wireless transmission path 4.

Similarly, the data transmitting / receiving unit 21 separates and restores the data unit from the multiplexed data stream supplied from the external device to the communication station 2, and passes the restored data unit to the wired / wireless line switching unit 22. . Further, the data transmission / reception unit 21 receives the data stream from either the transmission path 3 or 4 from the wired / wireless line switching unit 22, multiplexes the data units extracted from the data stream, and transfers the multiplexed data unit to the destination external device. Wired / wireless line switching unit 2
2 relays data exchanged between the data transmitting / receiving unit 21 and the communication station 1. The wired / wireless line switching unit 22 has a switching element therein, and the switching element is operated in accordance with the wired / wireless switching signal CO21 input to the communication station 2 to change the transmission path to be used. Or, switch to the wireless transmission path 4. Then, it relays data exchanged between the data transmitting / receiving unit 21 and the communication station 1. The wired synchronization establishing unit 23 has a function of establishing synchronization of a wired line with the communication station 1 of the other party. Wireless synchronization establishment unit 2
Reference numeral 4 has a function of establishing synchronization of a wireless line with the communication station 1 of the other party. The wire transmission / reception unit 26 has a function of enabling communication with the communication station 1 of the other party by a communication method corresponding to the wire transmission path 3. The wireless transmission / reception unit 27 has a function of enabling communication with the communication station 1 of the other party by a communication method corresponding to the wireless transmission path 4.

Next, the wired / wireless switching operation will be described.
First, the operation when switching from a wired line to a wireless line will be described. When the wired / wireless switching signal CO11 input to the communication station 1 instructs switching from wired to wireless, the wired / wireless line switching unit 12 of the communication station 1 connects via the wired transmission path 3 that has been used. It notifies the communication station 2 of the other party of a command to switch from wired to wireless. Thereafter, the wired / wireless line switching unit 12 of the communication station 1 switches the transmission path to be used from the wired transmission path 3 to the wireless transmission path 4. Similarly, the wired / wireless line switching unit 22 of the communication station 2 switches the transmission path to be used from the wired transmission path 3 to the wireless transmission path 4. afterwards,
Synchronization is established between the wireless synchronization establishing section 14 of the communication station 1 and the wireless synchronization establishing section 24 of the communication station 2. After the synchronization is established, wireless communication between the communication station 1 and the communication station 2 becomes possible. The transmission / reception of the transmission / reception data DA11 and DA21 is performed. Further, when the wired / wireless switching signal CO21 in the communication station 2 instructs switching from wired to wireless, the wired / wireless line switching unit 22 of the communication station 2 communicates with the other party via the wired transmission path 3 used so far. The communication station 1 is notified of an instruction to switch from wired to wireless. Thereafter, switching of the transmission path and establishment of synchronization are performed in the same manner as described above. A similar operation is performed when switching from a wireless line to a wired line.

[0007]

Since the conventional communication system is configured as described above, even if the transmission path is switched, it takes time to establish line synchronization on a new transmission path. There was a problem that data was lost due to momentary interruption.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a communication station, a communication switching method, and a communication system capable of instantaneously switching lines and preventing data loss. Aim.

[0009]

A communication station according to the present invention uses a wireless transmission unit capable of transmitting to a communication station of the other party using a wireless medium, and uses a wired medium for the communication station of the other party. A wire transmitting unit capable of performing transmission, a first notifying unit for notifying the communication station of the other party of the newly used medium, and a communication unit of the communication station of the other party via the newly used medium. A monitoring unit that monitors whether a line to the station has been established; and, after the monitoring unit detects that the line using the newly used medium has been established, a line using the medium that has been used previously. A second notification unit for notifying the communication station of the other party of the time when the communication station of the other party should shut down;
And a cutoff unit that cuts off the previously used medium line after the monitoring unit detects that the line using the newly used medium has been established.

[0010] The communication station according to the present invention determines the time when the blocking unit cuts off the communication using the previously used medium, and the time when the communication is stopped.
The notification unit notifies the communication station of the other party at the same time.

The communication station according to the present invention includes a transmission delay measuring unit for measuring a transmission delay with the communication station of the other party. The time when the notification unit 2 notifies the communication station of the other party is delayed by the delay.

[0012] A communication station according to the present invention comprises: a wireless receiving unit capable of receiving from a communication station of the other party via a wireless medium; and a cable capable of receiving from the communication station of the other party via a wired medium. The receiving unit, the first notified unit that notifies the newly used medium from the communication station of the other party, and the time at which the line of the previously used medium should be cut off from the communication station of the other party. It is provided with a second notified unit to be notified, and a cutoff unit that cuts off a line using a medium that has been used before at the above time.

[0013] A communication station according to the present invention comprises: a wireless receiving section capable of receiving from a communication station of the other party via a wireless medium; and a cable capable of receiving from the communication station of the other party via a wired medium. A receiving unit, a transmission delay measuring unit for measuring a transmission delay with the communication station of the other party, a first notified unit for notifying the newly used medium from the communication station of the other party, and a communication of the other party. A second notified unit that is notified by the station of the time at which the line using the previously used medium should be disconnected, and a time when the line using the previously used medium is delayed by the above-mentioned delay from the above-mentioned time. And a blocking unit for blocking.

[0014] In the communication switching method according to the present invention, a communication station capable of using a line using a wireless medium and a line using a wired medium notifies a communication station of the other party of a newly used medium.
After detecting that the line using the newly used medium has been established, and detecting that the line using the newly used medium has been established, the other party's communication using the line using the previously used medium is performed. The station notifies the communication station of the other party of the time to be cut off, and after detecting that the line using the newly used medium has been established, cuts off the line using the previously used medium.

In the communication switching method according to the present invention, a communication station that can use a line using a wireless medium and a line using a wired medium is notified of a medium to be newly used from a communication station of the other party, and the communication station of the other party is notified. Thus, the time when the line using the previously used medium should be cut off is notified, and the line using the previously used medium is cut off at the above time.

A communication system according to the present invention includes a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A possible wireless transmission unit, a wired transmission unit capable of transmitting to the second communication station using a wired medium, and a first communication unit that notifies the second communication station of a newly used medium. Notification section,
A monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium has been established; and a monitoring unit that has established the line using the newly used medium. A second notifying unit for notifying the second communication station of a time when the second communication station should cut off the line using the medium that has been used before after the monitoring unit detects the line using the medium previously used; After the monitoring unit detects that the line using the medium has been established, the first communication unit shuts off the line using the medium that has been used before. A wireless receiving unit capable of receiving from the first communication station via a wireless medium, a wired receiving unit capable of receiving from the first communication station via a wired medium, and newly used A first notified device that is notified of the medium from the first communication station; And a second notified unit for notifying from the first communication station when to disconnect the line using the previously used medium, and disconnecting the line using the previously used medium at the above time. And a second interrupting section.

A communication system according to the present invention includes a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A possible wireless transmission unit, a wired transmission unit capable of transmitting to the second communication station using a wired medium, and a first communication unit that notifies the second communication station of a newly used medium. Notification section,
A monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium has been established; and a monitoring unit that has established the line using the newly used medium. A second notifying unit that notifies the second communication station of a time when the second communication station should cut off a line using a medium that was previously used after the monitoring unit detects the line using the medium that has been used before; After the monitoring unit detects that a line using a medium has been established, a first blocking unit that cuts off a line using a medium that has been used previously and a reception unit via a wireless medium from the second communication station. A wireless receiving unit capable of performing communication, a wired receiving unit capable of performing reception from the second communication station via a wired medium, and a medium to be newly used notified from the second communication station. From the first notified unit and the second communication station, A second notified unit that is notified of a time at which a line using a medium that should be used should be cut off, and a second blocking unit that cuts off the line using a medium that has been used previously at the time, The second communication station is capable of transmitting to the first communication station using a wireless medium, and is capable of transmitting to the first communication station using a wired medium. A first transmission unit for notifying the first communication station of a newly used medium to the first communication station, and a line from the first communication station to the own station via the newly used medium. And a monitoring unit that monitors whether or not a line using a medium that has been used previously has been detected by the monitoring unit. The second communication for notifying the first communication station of the time when the communication station should be shut down. A first disconnection unit that disconnects a line using a medium that has been used before, after the monitoring unit detects that a line using the newly used medium has been established, and the first communication. A wireless receiving unit capable of receiving from a station via a wireless medium; a wired receiving unit capable of receiving from the first communication station via a wired medium; A first notified unit notified by one communication station, a second notified unit notified by the first communication station of a time when a line using a medium that has been used previously should be cut off, A second cut-off unit that cuts off a line using a medium that has been used before at the above time.

A communication station according to the present invention is capable of transmitting to a communication station of the other party using a wireless medium, and is capable of transmitting to the communication station of the other party using a wired medium. A wire transmitting unit, a notifying unit for notifying the communication station of the other party of the newly used medium, and whether a line from the communication station of the other party to the own station via the newly used medium is established. A monitoring unit that monitors whether a line using a medium that has been newly used has been established, After the monitoring unit detects that the line using the medium to be used is established, before the blocking unit cuts off the line using the previously used medium, the wireless transmission unit and the wired transmission unit In the same data unit Factors Signaling to transmit respectively, in which a transmission control unit for controlling the radio transmission unit and the wired transmitting unit.

A communication station according to the present invention comprises: a wireless receiving section capable of receiving from a communication station of a partner via a wireless medium; and a cable capable of receiving from the communication station of the partner via a wired medium. A receiving unit, a notified unit for notifying the newly used medium from the communication station of the other party, and whether a line from the communication station of the other party to the own station via the newly used medium is established A monitoring unit that monitors whether the line has been established, a blocking unit that blocks a line using a previously used medium after the monitoring unit detects that the line has been established, and a line that uses the newly used medium. After the monitoring unit detects that the connection has been established, before the cutoff unit cuts off the line using the previously used medium, the signal received by the wire reception unit is temporarily stored. The storage unit and the new After the monitoring unit detects that the line using the medium to be used has been established, before the blocking unit cuts off the line using the previously used medium, the signal received by the wireless reception unit is output. A wireless storage unit for temporarily storing, and an estimating unit for estimating an original signal based on the signal temporarily stored in the wired storage unit and the wireless storage unit. .

In the communication switching method according to the present invention, a communication station capable of using a line using a wireless medium and a line using a wired medium notifies a communication station of the other party of a newly used medium,
Detecting that the line using the newly used medium has been established, and detecting that the line using the newly used medium has been established, disconnecting the line using the previously used medium, After detecting that the line using the newly used medium has been established, before shutting down the line using the previously used medium, the same using the line using the wireless medium and the line using the wired medium is used. A signal originating from the data unit is transmitted.

In the communication switching method according to the present invention, a communication station capable of using a line using a wireless medium and a line using a wired medium is notified of a medium to be newly used from a communication station of the other party, After detecting that a line using a medium that has been newly used is established, and detecting that a line using a medium that is newly used has been established, the line using a medium that was previously used is cut off, and After the monitoring unit detects that a line with a medium has been established,
Before interrupting the line using the previously used medium, the signal received from the wired medium is temporarily stored, and the monitoring unit confirms that the line using the newly used medium has been established. After detecting, before interrupting the line by the previously used medium, temporarily store the signal received from the wireless medium, based on the temporarily stored signal, the original It is for estimating the signal.

A communication system according to the present invention includes a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A wireless transmission unit capable of performing transmission using a wired medium to the second communication station, and a notification unit configured to notify the second communication station of a newly used medium. A first monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium is established, and a monitoring unit that determines that the line is established. After the detection, the first blocking unit that cuts off the line using the previously used medium, and the monitoring unit detects that the line using the newly used medium has been established, and then uses the previously used line. Before the first cut-off unit cuts off the line by the medium, The second communication station, comprising: a wireless transmission unit and a transmission control unit that controls the wired transmission unit so that the line transmission unit and the wired transmission unit each transmit a signal originating from the same data unit. A wireless receiving unit capable of receiving from the first communication station via a wireless medium, a wired receiving unit capable of receiving from the first communication station via a wired medium, It monitors whether or not the notified unit notified of the medium to be used from the first communication station and the line from the first communication station to the own station via the newly used medium are established. A second monitoring unit, a second blocking unit configured to block the line using the medium that has been used after the monitoring unit detects that the line has been established, The monitoring unit detects that the line has been established And a wire storage unit for temporarily storing a signal received by the wire receiving unit before the second blocking unit cuts off the line using the medium used before, and the newly used line. After the monitoring unit detects that the line using the medium to be established has been established, and before the second blocking unit cuts off the line using the previously used medium, the radio reception unit receives the signal. A wireless storage unit for temporarily storing a signal, and an estimating unit for estimating an original signal based on the signal temporarily stored in the wired storage unit and the wireless storage unit It is.

A communication system according to the present invention includes a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A wireless transmission unit capable of performing transmission using a wired medium to the second communication station, and a notification unit configured to notify the second communication station of a newly used medium. A first monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium is established, and a line using the newly used medium is established. After the monitoring unit detects that the communication has been established, the monitoring unit detects that the first interruption unit that interrupts the line using the previously used medium and the line that is newly established using the medium is established. After that, the line using the medium previously used is connected to the first Before the disconnection unit shuts off, the transmission control unit that controls the wireless transmission unit and the wired transmission unit so that the wireless transmission unit and the wired transmission unit respectively transmit signals originating from the same data unit. A wireless receiving unit capable of receiving from the second communication station via a wireless medium, a wired receiving unit capable of receiving from the second communication station via a wired medium, and newly used A notified unit for notifying the medium from the second communication station; and a second unit for monitoring whether a line from the second communication station to the own station via the newly used medium is established. A monitoring unit, a second blocking unit that blocks a line using a medium that has been used before after the monitoring unit detects that the line has been established, and a line that uses the newly used medium is established. After the monitoring unit detects that A wire storing unit for temporarily storing a signal received by the wire receiving unit before the second blocking unit cuts off a line using a medium used before, and the newly used line After the monitoring unit detects that the line using the medium has been established, before the second blocking unit cuts off the line using the medium that has been used before, the signal received by the wireless reception unit is output. A wireless storage unit for temporarily storing, based on a signal temporarily stored in the wired storage unit and the wireless storage unit, an estimating unit for estimating an original signal, A second communication station capable of transmitting to the first communication station using a wireless medium, and capable of transmitting to the first communication station using a wired medium Notifying the first communication station of a wire transmission unit and a newly used medium A notifying unit, a first monitoring unit that monitors whether a line from the first communication station to the own station via the newly used medium is established, and a line using the newly used medium. After the monitoring unit detects that has been established,
A first blocking unit that cuts off a line using a previously used medium, and a medium that has been used before after the monitoring unit detects that the line using the newly used medium has been established. Controlling the wireless transmission unit and the wired transmission unit such that the wireless transmission unit and the wired transmission unit respectively transmit signals originating from the same data unit before the first interruption unit interrupts the line according to A transmission control unit, a wireless reception unit capable of receiving from the first communication station via a wireless medium, and a wired reception unit capable of receiving from the first communication station via a wired medium And a notified unit for notifying the newly used medium from the first communication station, and whether or not a line has been established from the first communication station to the own station via the newly used medium. A second monitoring unit for monitoring whether After the monitoring unit detects that a line using a newly used medium has been established, a second cutoff unit that cuts off a line using a previously used medium, and a line using the newly used medium After the monitoring unit detects that the connection has been established, the signal received by the wired receiving unit is temporarily stopped before the second blocking unit cuts off the line using the previously used medium. After the monitoring unit detects that the line using the newly used medium has been established with the storage unit for storing the wire, the second blocking unit cuts off the line using the previously used medium. Before, based on the signal temporarily stored in the wireless storage unit and the wired storage unit and the wireless storage unit for temporarily storing the signal received by the wireless reception unit,
And an estimator for estimating the original signal.

[0024]

Embodiments of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a diagram showing a first embodiment of the present invention. In FIG. 1, 11 is a data transmission / reception unit, 12 is a wired / wireless line switching unit, 13 is a wired synchronization establishing unit, 15
Is a used line monitoring unit, 14 is a wireless synchronization establishing unit, 16 is a wired transmitting and receiving unit, 17 is a wireless transmitting and receiving unit, 18 is a switch execution timing instructing unit, and 19 is a control signal transmitting and receiving unit. The communication station 1 includes a data transmitting / receiving unit 11, a wired / wireless line switching unit 12, a wired synchronization establishing unit 13, a wireless synchronization establishing unit 14, a used line monitoring unit 15, a wired transmitting / receiving unit 16, a wireless transmitting / receiving unit 17, and a switching execution timing. An instruction unit 18 and a control signal transmitting / receiving unit 19 are provided.

Reference numeral 21 is a data transmitting / receiving unit, 22 is a wired / wireless line switching unit, 23 is a wired synchronization establishing unit, 25 is a used line monitoring unit, 24 is a wireless synchronization establishing unit, 26 is a wired transmitting / receiving unit, and 27 is a wired transmitting / receiving unit. A wireless transmission / reception unit, 28 is a switching execution time instruction unit,
29 is a control signal transmitting / receiving unit. The communication station 2 includes a data transmitting / receiving unit 21, a wired / wireless line switching unit 22, a wired synchronization establishing unit 23, a wireless synchronization establishing unit 24, a used line monitoring unit 25,
The transmission / reception unit 26 includes a wired transmission / reception unit 26, a wireless transmission / reception unit 27, a switching execution timing instruction unit 28, and a control signal transmission / reception unit 29. 3 is a wired transmission path (wired medium), 4 is a wireless transmission path (wireless medium)
It is.

As in the system shown in FIG. 7, these communication stations (first communication station, second communication station) 1 and communication station (first communication station, second communication station) 2 It is located in buildings. The communication stations 1 and 2 are linked to each other via a wired transmission path 3 and a wireless transmission path 4. Each of the communication stations 1 and 2 can instruct the other communication station to switch the transmission path to be used.

In the communication station 1, the data transmitting / receiving unit 11
Separates and restores the data unit from the multiplexed data stream supplied to the communication station 1 from a plurality of external devices, and passes the restored data unit to the wired / wireless line switching unit 12. Further, the data transmission / reception unit 11 receives the data stream from either the transmission path 3 or 4 from the wired / wireless line switching unit 12, multiplexes the data units extracted from the data stream, and transfers the multiplexed data unit to the destination external device. That is, the data transmission / reception unit 11 controls transfer of messages, voices, images, and other user data from or to the external device. The wired / wireless line switching unit (blocking unit, first blocking unit, second blocking unit) 12 relays data exchanged between the data transmitting / receiving unit 11 and the communication station 2. This wired /
The wireless line switching unit 12 has a switching element therein, and the switching element is operated in accordance with the switching execution command signal CO18, and actually switches the transmission path to be used to the wired transmission path 3 or the wireless transmission path 4.

The wired synchronization establishing section 13 has a function of establishing the synchronization of the wired line with the communication station 2 of the other party. Specifically, the synchronization establishing unit 13 transmits a synchronization establishment instruction signal that the communication station 2 refers to for establishing synchronization to the communication station 2 via the wired transmission path 3 in accordance with an instruction of the control signal transmitting / receiving unit 19. With reference to a clock pulse component (for example, a time reference value) included in the synchronization establishment instruction signal coming from the communication station 2 via the wired transmission path 3, the reception operation timing in the own station 1 is associated with the clock pulse component. Also,
The wire synchronization establishment unit 13 generates a wire synchronization establishment state signal CO14 indicating whether or not the synchronization of the wire line from the communication station 2 to the communication station 1 has been established, and supplies this to the use line monitoring unit 15. . If the above association is successful, the wire synchronization establishment status signal CO14 means that synchronization of the wire line from the communication station 2 to the communication station 1 has been established.

Similarly, the wireless synchronization establishing section 14 has a function of establishing synchronization of the wireless line with the communication station 2 of the other party. Specifically, the synchronization establishing unit 14 transmits a synchronization establishment instruction signal, which the communication station 2 refers to for establishing synchronization, to the communication station 2 via the wireless transmission path 4 in accordance with an instruction from the control signal transmitting / receiving unit 19.
, And refers to a clock pulse component (time reference value) included in the synchronization establishment instruction signal arriving from the communication station 2 via the wireless transmission path 3, and the reception operation timing in the own station 1 is added to the clock pulse component. Is related. The wireless synchronization establishment unit 14 generates a wireless synchronization establishment state signal CO15 indicating whether or not synchronization of the wireless line from the communication station 2 to the communication station 1 has been established, and supplies this to the used line monitoring unit 15. . If the above association is successful, the wireless synchronization establishment status signal CO15 indicates that the synchronization of the wireless line from the communication station 2 to the communication station 1 has been established. However, the synchronization procedure by the synchronization establishing units 13 and 14 is not limited to the clock synchronization described above, and a frame synchronization or other synchronization procedure may be used.

The wire transmission / reception unit 16 has a function of enabling communication with the communication station 2 of the other party by a communication method corresponding to the wire transmission path 3. That is, when the wired / wireless line switching unit 12 enables the wired line, the wired transmission / reception unit 16 serves as a communication interface (wired transmission unit, wired reception unit) between the data transmission / reception unit 11 and the wired transmission path 3. Functioning, the data DA 12 is exchanged between the wired transmission / reception unit 16 and the wired / wireless line switching unit 12. Wireless transceiver 17
Has a function of enabling communication with the communication station 2 of the other party by a communication method corresponding to the wireless transmission path 4. That is, when the wired / wireless line switching unit 12 enables the wireless line, the wireless transmission / reception unit 17 serves as a communication interface (wireless transmission unit, wireless reception unit) between the data transmission / reception unit 11 and the wireless transmission path 4. Functioning, the data DA 13 is exchanged between the wireless transmission / reception unit 17 and the wired / wireless line switching unit 12.

The used line monitoring unit (monitoring unit) 15 can determine whether or not the synchronization of the wired line has been established by the synchronization establishment state signal CO14.
By using 15, it is possible to determine whether or not the synchronization of the wireless line has been established. Then, the used line monitoring unit 15 generates a used line monitoring signal CO16 indicating whether or not synchronization of each line is established, and supplies this to the control signal transmitting / receiving unit 19. The control signal transmission / reception unit 19 functions as a first notification unit that notifies the communication station of the other party of a medium to be newly used. That is, according to the wired / wireless switching signal CO11 supplied from an external device to the communication station 1, the control signal CO12 or CO13 is transmitted to the communication station 2 as a switching trigger signal. When switching from wired to wireless, a control signal CO12 is transmitted as a switching trigger signal via the wired transmission path 3,
It is delivered to the communication station 2. Conversely, when switching from wireless to wired, a control signal CO13 is delivered to the communication station 2 via the wireless transmission path 4 as a switching trigger signal. The control signal transmitting / receiving section 19 can receive a switching preparation completion signal from the communication station 2, and upon receiving the switching preparation completion signal, generates a switching execution instruction signal CO17 and sends it to the switching execution timing instruction section. 18.

The switching execution timing instructing unit 18 functions as a second notifying unit for notifying the communication station of the other party of the time when the communication station of the other party should cut off the line using the medium previously used. That is, when the switching execution instruction signal CO17 is received, the switching execution timing instruction signal CO18 is supplied to the wired / wireless line switching unit 12. This switching execution timing instruction signal CO
Reference numeral 18 is completely different from the above switching trigger signal. The switching trigger signal prompts the other communication station 2 to prepare for switching the transmission path, while the switching execution timing instruction signal indicates that the other communication station 2
Is issued after the completion of the switching preparation, and the change of the circuit in the own station 1 is urged at the time indicated by this signal. Also,
The switching execution timing instruction unit 18 transmits this switching execution timing instruction signal to the communication station 2 using the transmission path used so far.

At the time indicated by the switching execution time instruction signal CO18, the wired / wireless line switching unit 12 finally cuts off the circuit corresponding to the transmission line used so far and disconnects the line. Therefore, the wired / wireless line switching unit 12
Is configured to be able to maintain both the newly used transmission line and the existing transmission line for a while.

Further, when the communication station 2 issues a switching trigger signal, the control signal transmitting / receiving unit 19 sets the newly used medium as the first notified unit notified from the other communication station, and sets the switching trigger signal. Receive the signal. Control signal transmitting / receiving section 19
After receiving the switching trigger signal, confirms that the synchronization of the wireless line to be newly used has been established, and then returns a switching preparation completion signal to the communication station 2. Thereafter, the control signal transmission / reception unit 19 of the communication station 1 functions as a second notified unit that is notified of the time when the line using the medium used previously should be cut off from the communication station of the other party. That is, a switching execution timing instruction signal from communication station 2 is received. In this case, the control signal transmission / reception unit 19 directly supplies the switching execution timing instruction signal to the wired / wireless line switching unit 12. Thus, at the time indicated by the switching execution timing instruction signal created by the communication station 2, the wired / wireless line switching unit 1
2 cuts off the line by cutting off the circuit corresponding to the transmission line used so far.

In the communication station 2, the data transmitting / receiving unit 21
Separates and restores a data unit from a multiplexed data stream supplied to the communication station 2 from a plurality of external devices, and passes the restored data unit to the wired / wireless line switching unit 22. Further, the data transmission / reception unit 21 receives the data stream from either the transmission path 3 or 4 from the wired / wireless line switching unit 22, multiplexes the data units extracted from the data stream, and transfers the multiplexed data unit to the destination external device. That is, the data transmitting / receiving unit 21 controls the transfer of messages, voices, images, and other user data from or to the external device. The wired / wireless line switching unit (blocking unit, first blocking unit, second blocking unit) 22 relays data exchanged between the data transmitting / receiving unit 21 and the communication station 1. This wired /
The wireless line switching unit 12 actually switches the transmission path to be used to the wired transmission path 3 or the wireless transmission path 4 according to the switching execution command signal CO28.

The wired synchronization establishing section 23 has a function of establishing a wired line synchronization with the communication station 1 of the other party. Specifically, the synchronization establishing unit 23 transmits a synchronization establishment instruction signal which the communication station 1 refers to for establishing synchronization to the communication station 1 via the wired transmission path 3 according to the instruction of the control signal transmitting / receiving unit 29. With reference to a clock pulse component (for example, a time reference value) included in the synchronization establishment instruction signal coming from the communication station 1 via the wired transmission path 3, the reception operation timing in the own station 2 is associated with the clock pulse component. Also,
The wire synchronization establishment unit 23 generates a wire synchronization establishment status signal CO24 indicating whether or not the synchronization of the wire line from the communication station 1 to the communication station 2 has been established, and supplies this to the use line monitoring unit 25. . If the above association is successful, the wire synchronization establishment status signal CO24 means that the synchronization of the wire line from the communication station 1 to the communication station 2 has been established.

Similarly, the wireless synchronization establishing section 24 has a function of establishing synchronization of a wireless line with the communication station 1 of the other party. Specifically, the synchronization establishing unit 24 transmits a synchronization establishing instruction signal which the communication station 1 refers to for establishing synchronization via the wireless transmission path 4 to the communication station 1 according to the instruction of the control signal transmitting / receiving unit 29.
, And refers to a clock pulse component (for example, a time reference value) included in the synchronization establishment instruction signal arriving via the wireless transmission path 3 from the communication station 1. Relate timing. The wireless synchronization establishing unit 24 communicates from the communication station 1 to the communication station 2
A radio synchronization establishment state signal CO25 indicating whether or not the radio line has been synchronized to the
5 If the above association is successful, the wireless synchronization establishment status signal CO25 indicates that the synchronization of the wireless line from the communication station 1 to the communication station 2 has been established. However, the synchronization procedure by the synchronization establishing units 23 and 24 is not limited to the clock synchronization described above, and a frame synchronization or other synchronization procedure may be used.

The wire transmission / reception unit 26 has a function of enabling communication with the communication station 1 of the other party by a communication method corresponding to the wire transmission path 3. That is, the wired / wireless line switching unit 2
2 enables the wired line, the wired transmission / reception unit 26
Functions as a communication interface (wired transmitting unit, wired receiving unit) between the data transmitting / receiving unit 21 and the wired transmission path 3, and the data DA 22 is exchanged between the wired transmitting / receiving unit 26 and the wired / wireless line switching unit 22. Is done. The wireless transmission / reception unit 27 has a function of enabling communication with the communication station 1 of the other party by a communication method corresponding to the wireless transmission path 4. That is, when the wired / wireless line switching unit 22 enables the wireless line, the wireless transmitting / receiving unit 27 serves as a communication interface (wireless transmitting unit, wireless receiving unit) between the data transmitting / receiving unit 21 and the wired transmission path 3. Functioning, the data DA 23 is exchanged between the wireless transmission / reception unit 27 and the wired / wireless line switching unit 22.

The used line monitoring unit (monitoring unit) 25 can recognize whether or not the synchronization of the wired line has been established by the synchronization establishment state signal CO24.
With 25, it is possible to know whether or not the synchronization of the wireless line has been established. Then, the used line monitoring unit 25 generates a used line monitoring signal CO26 indicating whether or not synchronization of each line has been established, and supplies this to the control signal transmitting / receiving unit 29. The control signal transmitting / receiving unit 29 functions as a notifying unit or a first notifying unit for notifying the communication station of the other party of the newly used medium. That is, according to the wired / wireless switching signal CO21 supplied from the external device to the communication station 2, the control signal CO22 or CO23 is transmitted to the communication station 1 as a switching trigger signal. When switching from wired to wireless, a control signal CO22 is delivered to the communication station 1 via the wired transmission line 3 as a switching trigger signal. Conversely, when switching from wireless to wired, the control signal C
O23 is delivered to the communication station 1 via the wireless transmission path 4. The control signal transmitting / receiving section 29 can receive a switching preparation completion signal from the communication station 1, and upon receiving the switching preparation completion signal, generates a switching execution instruction signal CO27 and sends it to the switching execution timing instruction section. 28.

The switching execution timing instructing unit 28 functions as a second notifying unit that notifies the communication station of the other party of the time when the communication station of the other party should cut off the line using the medium that has been used before. That is, when the switching execution instruction signal CO27 is received, the switching execution timing instruction signal CO28 is supplied to the wired / wireless line switching unit 22. This switching execution timing instruction signal CO
28 is also completely different from the above switching trigger signal. The wired / wireless line switching unit 22 outputs the switching execution timing instruction signal CO2
At the time indicated by 8, the circuit corresponding to the transmission line used so far is finally cut off to disconnect the line. Therefore, the wired / wireless line switching unit 22 is also configured to be able to maintain both the newly used transmission line and the existing transmission line for a while.

Further, when the communication station 1 issues a switching trigger signal, the control signal transmission / reception section 29 transmits a new medium to be notified from the other communication station or the first communication section.
Receives the switching trigger signal. After receiving the switching trigger signal, the control signal transmitting / receiving unit 29 confirms that the synchronization of the newly used wireless channel has been established, and then returns a switching preparation completion signal to the communication station 1. Thereafter, the control signal transmission / reception unit 29 of the communication station 2 functions as a second notified unit that is notified of the time at which the line of the medium used previously should be cut off from the other communication station. That is, the switching execution timing instruction signal from the communication station 1 is received. In this case, the control signal transmitting / receiving unit 29
Supplies the switching execution timing instruction signal directly to the wired / wireless line switching unit 22. As a result, at the time indicated by the switching execution timing instruction signal created by the communication station 1, the wired / wireless line switching unit 22 cuts off the circuit corresponding to the transmission line used so far and disconnects the line. I do.

Next, the operation will be described. First, the operation when switching from a wired line to a wireless line will be described. As a switching trigger, when the wired / wireless switching signal CO11 supplied from the external device instructs the communication station 1 to switch from wired to wireless, the control signal transmitting / receiving unit 1 of the communication station 1
9 transmits a control signal CO12 as a trigger signal for switching to wireless via the wired transmission path 3 which has been used up to now to the communication station 2, thereby requesting the other communication station 2 to switch from wired to wireless. Notify. Also, the control signal transmitting / receiving unit 1
9 supplies the control signal CO13 to the wireless synchronization establishing unit 14, and prompts the synchronization establishing unit 14 to transmit a wireless synchronization establishment instruction signal to the communication station 2 via the wireless transmission path 4. When the wired / wireless switching signal CO 11 is supplied to the communication station 1, the wired / wireless line switching unit 12 makes a circuit so that not only the wired transmission line 3 used up to now but also the wireless transmission line 4 can be newly used. To change.

In the communication station 2, the control signal transmitting / receiving section 29
Receives the control signal CO22 as a switching trigger signal for wireless communication (the control signal CO12 in the communication station 1). After this reception, the control signal transmitting / receiving unit 29 sets the wireless synchronization establishing unit 2
The control signal CO 23 is supplied to the communication station 1, and the synchronization establishing unit 24 urges the communication station 1 to transmit a wireless synchronization establishment instruction signal to the communication station 1 via the wireless transmission path 4. When the communication station 2 receives the switching trigger signal, the wired / wireless line switching unit 22 changes the circuit so that the wireless transmission line 4 can be newly used in addition to the previously used wired transmission line 3. . Further, the control signal transmitting / receiving unit 29 confirms that the synchronization of the wireless line to be newly used is established by the used line monitoring signal CO26 from the used line monitoring unit 25, and then prepares for switching via the wired transmission line 3. A control signal CO22 as a completion signal is transmitted to the communication station 1.

In the communication station 1, the control signal transmitting / receiving unit 1
9 receives a control signal CO12 from the wired transmission line 3 as a switching preparation completion signal (control signal CO22 in the communication station 2), and synchronizes a wireless line to be newly used by the used line monitoring signal CO16 from the used line monitoring unit 15. Make sure that is established. After this confirmation is completed, the switching execution instruction signal CO17 is sent to the switching execution timing instruction unit 18 in the own station 1.
Supply. Upon receiving this, the switching execution timing instruction unit 18 of the communication station 1 supplies the switching execution timing instruction signal CO18 to the wired / wireless line switching unit 12. When receiving the switching execution timing instruction signal CO18, the wired / wireless line switching unit 12
At the switching time designated by this signal, the circuit corresponding to the wired transmission line used so far is cut off to disconnect the line, and the switching of the transmission line from the wired to the wireless is completed. That is, actual switching is performed. Prior to the line disconnection, the switching execution timing instruction unit 18 transmits a switching execution timing instruction signal to the communication station 2 by using the wire transmission path used so far.

In the communication station 2, the control signal transmitting / receiving unit 2
As soon as 9 receives the switching execution timing instruction signal from the communication station 1, the control signal transmission / reception section 29 supplies the switching execution timing instruction signal to the wired / wireless line switching section 22 of its own station 2, and the wired / wireless line switching section. At the switching time pointed by this signal, the circuit 22 cuts off the circuit by cutting off the circuit corresponding to the wire transmission path used so far, and completes the switching of the transmission path from wired to wireless. That is, actual switching is performed.

As can be understood from the above, the switching timing at which switching execution is instructed by the switching timing instruction signal is determined as follows. That is, when the communication station 1 receives the switching preparation completion signal from the communication station 2 and the communication station 1 is in the middle of transmitting or receiving a certain user data file, it is predicted that the transmission or reception will be completed. The switching timing is determined at a timing later than the timing. Prediction of completion is possible by referring to the entire file length indicated in the data unit constituting the user data file.

As described above, according to the first embodiment, there is obtained an effect that line switching can be performed without an instantaneous interruption and data loss is prevented. FIG. 2 is a flow diagram showing the above processing flow. In the first embodiment, the switching is performed at the communication station 1 and the communication station 2.
The communication station 1 and the communication station 2 execute the switching at the time designated by the same switching execution time instruction signal generated by the communication station 11 without independently determining the communication stations 1 and 2.
, The switching of the transmission path can be executed simultaneously, and the power consumption can be minimized. Further, both of the communication stations 1 and 2 can instruct the other to switch the line. When the wired / wireless switching signal CO11 supplied from an external device to the communication station 1 instructs switching from wireless to wired, switching from a wireless line to a wired line is performed in this embodiment. This switching can be performed by a procedure similar to the above.

In this embodiment, a single wired transmission line 3
And a single wireless transmission path 4 is provided, but is not intended to limit the invention to this disclosure. It is also possible to provide two wired transmission paths for forward transmission and reverse transmission and two wireless transmission paths for forward transmission and reverse transmission between the communication stations 1 and 2. . In this case, in consideration of the characteristics of the transmission path for the forward transmission and the reverse transmission, the use environment, and other factors, the transmission path switching for the reverse transmission is performed at an appropriate time from the execution of the transmission path switching for the forward transmission. It is also possible to execute

The above description has exemplified the operation in the case where the wired / wireless switching signal CO11 supplied from the external device to the communication station 1 instructs switching from wired to wireless as a trigger for switching. However, the communication station 2
May be supplied with a wired / wireless switching signal CO21 from an external device. The operation when the wired / wireless switching signal CO21 instructs switching from wired to wireless is performed in a procedure reverse to the above. In this case, a switching trigger signal is transmitted from the communication station 2 to the communication station 1, and a switching preparation completion signal is transmitted from the communication station 1 to the communication station 2 in response thereto. 1, a switching execution timing instruction signal is transmitted.
Also, when the wired / wireless switching signal CO21 supplied from the external device to the communication station 2 instructs switching from wireless to wired, switching from wireless to wired is also performed in this embodiment. . This switching can be performed in a similar procedure.

Embodiment 2 FIG. 3 shows a second embodiment of the present invention. In the figure, reference numeral 110 denotes a wired reception buffer, and 111 denotes a wireless reception buffer. The communication station 1 includes a data transmission / reception unit 11, a wired / wireless line switching unit 12, a wired synchronization establishing unit 13, a wireless synchronization establishing unit 14, a used line monitoring unit (a monitoring unit, a first monitoring unit, a second monitoring unit). Unit) 15, wired transmission / reception unit 16, wireless transmission / reception unit 17,
A control signal transmission / reception unit 19, a wired reception buffer 110,
The wireless reception buffer 111 is provided. 210 is a wired receiving buffer, and 211 is a wireless receiving buffer. The communication station 2 includes a data transmitting / receiving unit 21, a wired / wireless line switching unit 22, a wired synchronization establishing unit 23, a wireless synchronization establishing unit 24, and a used line monitoring unit (a monitoring unit, a first monitoring unit, a second monitoring unit). Unit) 25, wired transmission / reception unit 26, wireless transmission / reception unit 2
7. Control signal transmission / reception unit 29, wired reception buffer 21
0, a wireless reception buffer 211 is provided.

Unlike the first embodiment, the second embodiment
In this case, the switching execution timing indicating sections 18 and 28 are not provided, and the switching execution timing indicating signal for designating the actual switching execution timing is not generated. Therefore, each communication station does not instruct a device in the station itself or the communication station of the other party about a specific switching execution time. Instead, the receiving buffers 110, 111, 21
0 and 211 are used for diversity selection in order to prevent loss of the user data file.

In the second embodiment, when wired transmission is possible, the wired transmission / reception station 16 or 2
The wired data unit group received in step 6 is temporarily stored in the receiving buffer (wired storage unit) 110 or 210, and the data units are sequentially read from the receiving buffer 110 or 210 in FIFO format according to a prescribed cycle, and The data is transferred to the data transmitting / receiving unit 11 or 21 via the wireless line switching unit 12 or 22. As described above, the reception buffer 110 or 210 has a function of accumulating the user data received through the wired line. The reception buffer 110 or 210 may be used to synchronize user data arriving via the wired transmission line 3 from the communication station 2 or 1 of the other party. In addition, when switching from a wired line to a wireless line or from a wireless line to a wired line, the reception buffer 110 or 210 switches the data unit for diversity selection to the wired / wireless line switching unit 12 or 22. Play a role in providing.

When wireless transmission is possible, a group of wireless data units received by the wireless transmission / reception station 17 or 27 from the wireless transmission path 4 is temporarily stored in a reception buffer (wireless storage unit) 111 or 211. Receive buffer 111 or 211 in FIFO format according to specified cycle
The data units are sequentially read out from the data transfer unit 11 and transferred to the data transmitting / receiving unit 11 or 21 via the wired / wireless line switching unit 12 or 22. As described above, the reception buffer 111 or 211 has a function of accumulating the user data received through the wireless channel. Receive buffer 111 or 211
May be used to synchronize user data arriving via the wireless transmission path 4 from the communication station 2 or 1 of the other party. In addition, when switching from a wired line to a wireless line or from a wireless line to a wired line, the reception buffer 111 or 211 switches the data unit for diversity selection to the wired / wireless line switching unit 12 or 22. Play a role in providing.

In the communication station 1, the reception buffer 11
The wired / wireless line switching unit 12 that receives data units from 0 and 111 has a function of diversity selection, and the wired / wireless line switching unit 22 that receives data units from the receiving buffers 210 and 211 in the communication station 2 also has a function. It has a function of diversity selection. More specifically, the wired / wireless line switching unit (estimating unit) 12 is configured based on the data unit read from the wired receiving buffer 110 and the data unit read from the wireless receiving buffer 111. , Estimate the original data unit. Further, the wired / wireless line switching unit (estimating unit) 22 determines the original data unit read from the wired reception buffer 210 and the data unit read from the wireless reception buffer 211 based on the original data unit. Estimate the data unit.

In order for the transmission destination to realize such a selection technique,
Preferably, the source can transmit signals originating from the same data unit over both wireless and wired media.
For this reason, the communication station 1 detects the establishment of the line using the medium to be newly used, and then, before shutting down the line using the medium used before, the data transmitting / receiving unit (transmission control unit). The control unit 11 controls the wireless transmission / reception unit 17 and the switching execution time instruction unit 18 so that the wireless transmission / reception unit 17 and the switching execution time instruction unit 18 transmit signals originating from the same data unit. Also in the communication station 2, after detecting that the line using the newly used medium has been established, and before cutting off the line using the previously used medium, the data transmission / reception unit (transmission control unit) 21 The wireless transmission / reception unit 27 and the switching execution timing instruction unit 28 are controlled such that the wireless transmission / reception unit 27 and the switching execution timing instruction unit 28 transmit signals originating from the same data unit, respectively.

Next, the operation will be described. First, the operation when switching from a wired line to a wireless line will be described. When the wired / wireless switching signal CO11 supplied from the external device to the communication station 1 instructs switching from wired to wireless,
The control signal transmission / reception unit 19 of the communication station 1 transmits a control signal CO12 as a trigger signal for switching to wireless to the communication station 2 via the wired transmission path 3 which has been used so far. To the switch request from the wired to the wireless. Further, the control signal transmitting / receiving unit 19 supplies the control signal CO13 to the wireless synchronization establishing unit 14, and the synchronization establishing unit 14 sends the wireless synchronization establishing instruction signal via the wireless transmission path 4 to the communication station 2.
To send to. When the wired / wireless switching signal CO 11 is supplied to the communication station 1, the wired / wireless line switching unit 12 makes a circuit so that not only the wired transmission line 3 used up to now but also the wireless transmission line 4 can be newly used. To change.

In the communication station 2, the control signal transmitting / receiving section 29
Receives the control signal CO22 as a switching trigger signal for wireless communication (the control signal CO12 in the communication station 1). After this reception, the control signal transmitting / receiving unit 29 sets the wireless synchronization establishing unit 2
The control signal CO 23 is supplied to the communication station 1, and the synchronization establishing unit 24 urges the communication station 1 to transmit a wireless synchronization establishment instruction signal to the communication station 1 via the wireless transmission path 4. When the communication station 2 receives the switching trigger signal, the wired / wireless line switching unit 22 changes the circuit so that the wireless transmission line 4 can be newly used in addition to the previously used wired transmission line 3. . Then, the control signal transmitting / receiving unit 29 confirms that the synchronization of the wireless line to be newly used has been established by the used line monitoring signal CO26 from the used line monitoring unit 25, and then prepares for switching via the wired transmission line 3. A control signal CO22 as a completion signal is transmitted to the communication station 1. Thereafter, the control signal transmission / reception unit 29 supplies the switching execution instruction signal CO27 to the wired / wireless line switching unit 22 of the own station 2, and the wired / wireless line switching unit 22 corresponds to the wired transmission line used so far. The circuit to be connected is cut off and the line is immediately disconnected, and the switching of the transmission path from wired to wireless is completed. That is, actual switching is performed.

In the communication station 1, the control signal transmitting / receiving unit 1
9 receives a control signal CO12 from the wired transmission line 3 as a switching preparation completion signal (control signal CO22 in the communication station 2), and synchronizes a wireless line to be newly used by the used line monitoring signal CO16 from the used line monitoring unit 15. Make sure that is established. After the completion of this confirmation, the switching execution instruction signal CO1 is sent to the wired / wireless line switching unit 12 in the own station 1.
7 is supplied. Upon receiving this, the wired / wireless line switching unit 12 immediately cuts off the circuit corresponding to the wired transmission line used so far, disconnects the line, and completes the switching of the transmission line from wired to wireless. That is, actual switching is performed.

When the wired / wireless switching signal CO11 supplied from an external device to the communication station 1 instructs switching from wireless to wired, switching from a wireless line to a wired line is performed in this embodiment. Done. This switching can be performed by a procedure similar to the above. Conversely, the wired / wireless switching signal CO21 may be supplied to the communication station 2 from an external device. The operation when the wired / wireless switching signal CO21 instructs switching from wired to wireless is performed in a procedure reverse to the above. In this case, a switching trigger signal is transmitted from the communication station 2 to the communication station 1, and in response to this, a switching preparation completion signal is transmitted from the communication station 1 to the communication station 2, and both stations immediately execute the actual switching. I do. Also, when the wired / wireless switching signal CO21 supplied from the external device to the communication station 2 instructs switching from wireless to wired, switching from wireless to wired is also performed in this embodiment. . This switching can be performed in a similar procedure.

In the second embodiment, at the actual switching stage, the actual switching is executed even during the transfer of a certain user data file. When a new line is established, the source station of the user data file continues transmission of user data through both the new line and the previously used line, and prepares for the interruption of the previously used line. . That is, data units are transmitted and received by both wireless and wired lines from the establishment of a new line to the interruption of the line used so far.

For example, if the communication station 1 is in the process of receiving a user data file at the switching stage, the process from the establishment of a new line to the interruption of the line used so far is not limited to that of the transmission source. The communication station 2 transmits data units by both wireless and wired lines. In the communication station 1 of the transmission destination, the transmission / reception units 16 and 17 receive the wired data unit and the wireless data unit originating from the same data unit from the transmission paths 3 and 4, respectively.
111.

The wired data unit read from the wired receiving buffer 110 and the wireless data unit read from the wireless receiving buffer 111 are supplied to the wired / wireless line switching unit 12. The wired / wireless line switching unit 12 selects a preferred one of the wired data unit and the wireless data unit. As a specific technique of the selection, for example, if the electric field strength of the radio wave is above a threshold, a radio data unit may be selected, or a data unit in which no error is detected may be selected. Good.

Until the line used so far is cut off,
The wired / wireless line switching unit 12 performs this selection also for the subsequent data unit. Accordingly, the user can restore the entire user data file while selecting the selected suitable data unit at the transmission destination, thereby preventing loss of data in the user data file.

In the switching stage, if the communication station 2 of the other party is in the process of receiving a user data file, the process from the establishment of a new line to the interruption of the line used so far is the communication station of the transmission source. 1 transmits a data unit through both wireless and wired lines. In the communication station 2, the wired / wireless line switching unit 22 uses the wired data unit read from the wired reception buffer 210 and the wireless data unit read from the wireless reception buffer 211, as described above. A diversity choice is made in the same way. Therefore, loss of data in the user data file is prevented.

As described above, according to the second embodiment, line switching can be performed without any instantaneous interruption, and data loss can be prevented without specifying the execution time of switching to the other communication station. The effect is obtained. FIG. 4 is a flow diagram showing the above processing flow.

Embodiment 3 FIG. 5 is a diagram showing a third embodiment of the present invention, in which 112 and 212 are clocks, and 113 and 213 are transmission delay measuring units. The communication stations 1 and 2 include transmission delay measuring units 113 and 213, respectively, in addition to the same components as those in the first embodiment.

Next, the operation will be described. The transmission delay measuring units 113 and 213 measure the transmission delay Δt with reference to the corresponding clocks 112 and 212. The principle of measuring the transmission delay will be described with reference to FIG. As shown in FIG. 6, it is assumed that the communication station 2 transmits a delay measurement request to the communication station 1 at time t1. Upon receiving the delay measurement request, the communication station 1 returns a delay measurement response. The communication station 2 that has received the delay measurement request processes it at time t2. The difference between times t1 and t2 is considered to be equivalent to twice the transmission delay Δt. Therefore, communication station 2
Then, the transmission delay measuring unit 213 can recognize the times t1 and t2 and calculate the transmission delay Δt. Conversely, when the communication station 1 transmits the delay measurement request, the transmission delay measurement unit 113 of the communication station 1 can also calculate the transmission delay Δt.

The measurement of the transmission delay Δt may be performed at an appropriate time at any time. Since the communication stations 1 and 2 can be linked to each other via the wired transmission path 3 and the wireless transmission path 4, the transmission delay measuring units 113 and 213 measure the transmission delay Δt for both transmission paths. The measured transmission delay Δt is stored in the control signal transmitting / receiving unit 19 or 29.

The operation for switching the line is basically the same as the operation of the first embodiment. However, Embodiment 3 is different from Embodiment 1 in the timing of switching performed by each communication station. As shown in FIG.
It is assumed that the communication station 1 has transmitted a switching trigger signal to the communication station 2.
In this case, the time when the communication station 1 cuts off the line used so far (performs actual switching) is t3, whereas the time when the communication station 2 cuts off the line used so far is t3. Is time t3 + Δt.

That is, even if the time specified by the switching execution time instruction signal transmitted from the communication station 1 to the communication station 2 is the time t3, the communication station 2 adds the transmission delay Δt to the time t3 and sets the old time at the time t3 + Δt. Cut off the line. Alternatively, communication station 1
In (2), Δt may be added to t3 so that the time specified by the switching execution time instruction signal transmitted from the communication station 1 to the communication station 2 may be the time t3 + Δt.

This advantage will be described below. When the communication station 1 receives the switching preparation completion signal from the communication station 2, the communication station 1
If a certain user data file is being transmitted, the control signal transmitting / receiving unit 19 determines the switching time at a time later than the time when the transmission is expected to be completed. Prediction of completion is possible by referring to the entire file length indicated in the data unit constituting the user data file. Strictly speaking, the completion of the reception of the entire user data file at the other communication station 2 is delayed by the transmission delay Δt from the completion of the transmission at the communication station 1. Accordingly, the communication station 2 cuts off the old line at time t3 + Δt, thereby completely preventing file loss.

Further, in order to completely prevent the loss of the file, a transmission buffer is provided in the communication station of the transmission source, and after switching the line, a data unit is read from the buffer to restart the transmission. Since there is no need for steps,
Line switching can be performed quickly and easily. Since the transmission delay is accurately measured by the transmission delay measuring unit 213, it is not necessary to make the interruption delay longer than necessary.

When the communication station 1 receives the switch preparation completion signal from the communication station 2 and the communication station 1 is in the process of receiving a certain user data file, after the reception is completed, the switching execution timing instruction is issued. The signal may be transmitted to the communication station 2.

As described above, according to the third embodiment, there is an effect that the line can be switched without any instantaneous interruption, and data loss is prevented. Further, line switching can be executed in a short time from a comprehensive viewpoint.

[0075]

As described above, according to the present invention, a radio transmission unit capable of transmitting to a communication station of a partner using a wireless medium, and a transmission unit using a wired medium for the communication station of the partner , A first notification unit for notifying the communication station of the other party of the newly used medium, and a local station via the medium of the newly used communication station from the communication station of the other party. A monitoring unit that monitors whether or not the line to the newly used medium has been established; and, after the monitoring unit has detected that the line using the newly used medium has been established, A second notifying unit for notifying the communication station of the other party of the time at which the communication station should be shut down, and a second notifying unit which has previously been used after the monitoring unit detects that the line using the newly used medium has been established. Block the line by the medium Since it is configured to include a part, can be switched between lines to hitless, there are effects such as loss of data is prevented.

According to the present invention, the timing at which the blocking unit blocks the communication using the medium used previously and the timing at which the second notification unit notifies the other communication station are simultaneous. Therefore, it is possible to switch the transmission path at both communication stations at the same time, and it is possible to minimize power consumption.

According to the present invention, the transmission delay measuring unit for measuring the transmission delay with the communication station of the other party is provided. Since the notification unit notifies the communication station of the other party at a time delayed by the delay, data loss is more reliably prevented, and line switching can be executed in a short time from a comprehensive viewpoint. Has the effect of

According to the present invention, a wireless receiving unit capable of receiving from a communication station of the other party via a wireless medium, and a wired receiving unit capable of receiving from the communication station of the other party via a wired medium And a first notified unit for notifying the newly used medium from the communication station of the other party, and a time for cutting off the line by the medium used previously is notified from the communication station of the other party. Is configured to include a second notified unit and a cutoff unit that cuts off a line using a previously used medium at the above time, so that line switching can be performed without an instantaneous interruption and data loss is prevented. There are effects such as being done.

According to the present invention, a wireless receiving unit capable of receiving from a communication station of the other party via a wireless medium, and a wired receiving unit capable of receiving from the communication station of the other party via a wired medium A transmission delay measuring unit for measuring a transmission delay with the communication station of the other party, a first notified unit for notifying the newly used medium from the communication station of the other party, and A second notified unit to be notified of a time when a line using a previously used medium should be cut off, and a line to be cut off using a previously used medium at a time later than the above time by the delay. Since it is configured to have a cut-off unit, line switching can be performed without an instantaneous interruption, data loss can be more reliably prevented, and line switching can be executed in a short time from a comprehensive viewpoint. effective.

According to the present invention, the communication station that can use the line using the wireless medium and the line using the wired medium notifies the communication station of the other party of the newly used medium, and uses the medium that is newly used. After detecting that the line has been established and detecting that the line using the newly used medium has been established, the partner station determines when the communication station of the other party should cut off the line using the previously used medium. The communication switching method of notifying the communication station of the above and detecting that the line using the newly used medium has been established, and then disconnecting the line using the previously used medium. Therefore, there is an effect that the line can be switched without any instantaneous interruption and data loss is prevented.

According to the present invention, the communication station that can use the line using the wireless medium and the line using the wired medium is notified of the medium to be newly used from the communication station of the other party. The communication switching method is characterized in that the time when the line using the medium used should be cut off is notified, and the line using the medium used previously is cut off at the above-mentioned time. In addition, there is an effect that the line can be switched and data loss is prevented.

According to this invention, it is possible to provide a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A wireless transmission unit, a wired transmission unit capable of transmitting to the second communication station using a wired medium, and a first notification unit for notifying the second communication station of a newly used medium. And a monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium has been established, and that a line using the newly used medium has been established. After the monitoring unit detects, the second notification unit that notifies the second communication station of a time when the second communication station should cut off the line using the medium that has been used before, and the newly notified After the monitoring unit detects that a line using the medium to be used has been established, And a first blocking unit for blocking the line by the medium that has been, the second communication station,
A wireless receiving unit capable of receiving from the first communication station via a wireless medium; a wired receiving unit capable of receiving from the first communication station via a wired medium; A first notified unit for notifying a medium to be transmitted from the first communication station, and a second notification unit for notifying from the first communication station the time at which the line using the medium previously used should be cut off. Since the system is provided with the notified unit and the second cutoff unit that cuts off the line using the medium previously used at the above time, the line can be switched without any instantaneous interruption, and data loss is prevented. There are effects such as

According to the present invention, it is possible to provide a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A wireless transmission unit, a wired transmission unit capable of transmitting to the second communication station using a wired medium, and a first notification unit for notifying the second communication station of a newly used medium. And a monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium has been established, and that a line using the newly used medium has been established. A second notifying unit that notifies the second communication station of a time when the second communication station should cut off a line using a medium that has been used before, after the monitoring unit detects the After the monitoring unit detects that the line using the medium to be used has been established, A first cut-off unit for cutting off the line by the medium, a wireless receiving unit capable of receiving from the second communication station via a wireless medium, and a wireless receiving unit from the second communication station via a wired medium. A wired receiving unit capable of performing reception, a first notified unit that is notified of a newly used medium from the second communication station, and
A second notified unit for notifying a time when the line using the medium used before should be cut off, and a second blocking unit for cutting off the line using the medium used previously at the time. The second communication station can transmit to the first communication station using a wireless medium; and the wireless communication unit can perform transmission to the first communication station using a wired medium. And a first notifying unit for notifying the first communication station of a newly used medium from the first communication station to the own station via the newly used medium. A monitoring unit that monitors whether or not the line has been established; and, after the monitoring unit detects that the line using the newly used medium has been established, the line using the medium that was previously used is replaced with the second line. A second notifying the first communication station of a time when the first communication station should shut down; A notifying unit, a first blocking unit that cuts off a line using a medium that has been used before after the monitoring unit detects that a line using the newly used medium has been established, A wireless receiving unit capable of receiving from a communication station via a wireless medium, a wired receiving unit capable of receiving from the first communication station via a wired medium, and a medium newly used. A first notified unit notified from the first communication station, and the first communication station,
A second notified unit that is notified of a time when a line using a previously used medium should be cut off, and a second blocking unit that cuts off the line using a previously used medium at the above-mentioned time. With such a configuration, it is possible to issue an instruction to switch the line from either of the two communication stations to the other, to switch the line without an instantaneous interruption, and to prevent data loss.

According to the present invention, a wireless transmission unit capable of transmitting to a communication station of the other party using a wireless medium and a wired transmission unit capable of transmitting to the communication station of the other party using a wired medium A transmitting unit, a notifying unit that notifies the communication station of the other party of the newly used medium, and whether or not a line from the communication station of the other party to the own station via the newly used medium is established. A monitoring unit that monitors, a blocking unit that disconnects a line using a medium that was previously used after the monitoring unit detects that the line using the newly used medium has been established, and a blocking unit that uses the newly used medium. After the monitoring unit detects that the line using the medium has been established, the wireless transmission unit and the wired transmission unit use the same data before the interruption unit interrupts the line using the previously used medium. Due to unit Since the wireless transmission unit and the transmission control unit for controlling the wired transmission unit are provided so as to transmit the signals, the line can be switched without any instantaneous interruption, and the switching to the communication station of the other party is executed. There is an effect that data loss is prevented without specifying the time.

According to the present invention, a wireless receiving unit capable of receiving from a communication station of the other party via a wireless medium and a wired receiving unit capable of receiving from the communication station of the other party via a wired medium And a notified unit for notifying the newly used medium from the communication station of the other party, and whether or not a line from the communication station of the other party to the own station via the newly used medium is established. A monitoring unit for monitoring, after the monitoring unit detects that the line has been established, a disconnection unit for disconnecting a line using a previously used medium, and a line using the newly used medium is established. After the monitoring unit detects that the signal has been received by the wired receiving unit before the blocking unit cuts off the line using the previously used medium. And the above newly used After the monitoring unit detects that the line using the medium to be established has been established, before the blocking unit cuts off the line using the previously used medium, the signal received by the wireless reception unit is temporarily stopped. Based on the signal stored in the wireless storage unit and the signal temporarily stored in the wireless storage unit, the wireless storage unit to be stored in the wireless storage unit, and configured to include an estimating unit to estimate the original signal, The line can be switched without an instantaneous interruption, and there is such an effect that data loss is prevented even if the execution time of the switching is not specified by the communication station of the other party.

According to the present invention, the communication station that can use the line using the wireless medium and the line using the wired medium notifies the communication station of the other party of the newly used medium, and uses the medium that is newly used. After detecting that the line has been established and detecting that the line with the newly used medium has been established, the line with the previously used medium is cut off, and the line with the newly used medium is used. After detecting that the line has been established, before shutting down the line using the previously used medium, the signals originating from the same data unit are respectively used using the line using the wireless medium and the line using the wired medium. Since it was configured to send,
The line can be switched without an instantaneous interruption, and there is an effect that data loss is prevented without specifying the execution time of the switching for the other communication station.

According to the present invention, a communication station that can use a line using a wireless medium and a line using a wired medium is notified of a newly used medium from the communication station of the other party, After detecting that the line has been established and detecting that the line with the newly used medium has been established, the line with the previously used medium is cut off, and the line with the newly used medium is used. After the monitoring unit detects that the line has been established, the signal received from the wired medium is temporarily stored before the line using the previously used medium is cut off, and the new use is performed. After the monitoring unit detects that the line by the medium to be established has been established, before the line by the previously used medium is cut off, the signal received from the wireless medium is temporarily stored. Since the original signal is estimated on the basis of the temporarily stored signal, the line can be switched without any instantaneous interruption, and even if the execution time of the switching is not specified by the other communication station. This has the effect of preventing data loss.

According to the present invention, it is possible to provide a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A wireless transmission unit, a wired transmission unit capable of transmitting to the second communication station using a wired medium, a notification unit for notifying the second communication station of a newly used medium, A first monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium is established, and the monitoring unit detects that the line has been established; Later, after the first blocking unit that cuts off the line using the previously used medium and the monitoring unit detects that the line using the newly used medium has been established, the first blocking unit uses the previously used medium. Before the first cutoff unit cuts off the line by the medium, The wireless transmission unit and the transmission control unit that controls the wired transmission unit so that the wired transmission unit transmits signals originating from the same data unit, respectively, and the second communication station includes: A wireless receiving unit capable of receiving from a communication station via a wireless medium;
A wire receiving unit that can receive data from the first communication station via a wired medium;
A notified unit notified by the communication station of the first communication station, a second monitoring unit that monitors whether a line from the first communication station to the own station via the newly used medium is established, After the monitoring unit detects that the line has been established, the second blocking unit that blocks the line using the previously used medium, and the second blocking unit that detects that the line using the newly used medium has been established. A wire storing unit for temporarily storing a signal received by the wire receiving unit before the second blocking unit cuts off the line using the medium used before after the monitoring unit detects the line; After the monitoring unit detects that the line using the newly used medium has been established, and before the second cutoff unit cuts off the line using the previously used medium, Radio that temporarily stores the signal received by the unit A storage unit, based on the temporarily stored signal to the wired for storage unit and the radio for storage section,
Since it is configured to include the estimating unit for estimating the original signal, the line can be switched without any instantaneous interruption, and the first communication station does not need to specify the execution time of the switching from the first communication station to the second communication station. This has the effect of preventing data loss.

According to the present invention, it is possible to provide a first communication station and a second communication station, and the first communication station can transmit to the second communication station using a wireless medium. A wireless transmission unit, a wired transmission unit capable of transmitting to the second communication station using a wired medium, a notification unit for notifying the second communication station of a newly used medium, A first monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium has been established, and that a line using the newly used medium has been established. After the monitoring unit has detected, a first blocking unit that cuts off the line using the medium that has been used previously, and after the monitoring unit detects that the line using the newly used medium has been established. The first cutoff unit cuts off the line using the medium previously used. And a transmission control unit that controls the wireless transmission unit and the wired transmission unit so that the wireless transmission unit and the wired transmission unit respectively transmit signals originating from the same data unit. A wireless receiving unit capable of receiving from a station via a wireless medium; a wired receiving unit capable of receiving from the second communication station via a wired medium; A notified unit notified from the second communication station, a second monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium has been established, After the monitoring unit detects that the line has been established, the second interruption unit that interrupts the line using the previously used medium and the second interruption unit that establishes the line using the newly used medium. After detection by the monitoring unit, Before the second cutoff unit cuts off the line using the medium, the wire storage unit for temporarily storing the signal received by the wire reception unit and the line using the newly used medium are connected. After the monitoring unit detects the establishment, the signal received by the wireless receiving unit is temporarily stored before the second blocking unit cuts off the line using the previously used medium. And a estimating unit for estimating an original signal based on the signal temporarily stored in the wired storing unit and the wireless storing unit, and the second communication Bureau,
A wireless transmission unit capable of transmitting to the first communication station using a wireless medium, a wired transmission unit capable of transmitting to the first communication station using a wired medium, A notifying unit for notifying the first communication station of the medium to be used; and a first unit for monitoring whether a line from the first communication station to the own station via the newly used medium is established. A monitoring unit, a first blocking unit that disconnects a line using a previously used medium after the monitoring unit detects that a line using the newly used medium is established, After the monitoring unit detects that the line using the medium to be used has been established, before the first blocking unit cuts off the line using the previously used medium, the wireless transmitting unit and the wired line The transmitting unit separates the signals originating from the same data unit A transmission control unit for controlling the wireless transmission unit and the wired transmission unit so as to communicate with the wireless communication unit; a wireless reception unit capable of receiving from the first communication station via a wireless medium; A wired receiving unit capable of receiving from a station via a wired medium; a notified unit notified of a newly used medium from the first communication station; and a newly notified unit from the first communication station. A second monitoring unit that monitors whether a line to the own station has been established via the medium to be used, and after the monitoring unit detects that the line by the newly used medium has been established, A second blocking unit that cuts off a line using a previously used medium, and a medium that has been used before after the monitoring unit detects that the line using the newly used medium has been established. Before the second cutoff unit cuts off the line by The cable storage unit for temporarily storing the signal received by the cable reception unit, and the cable storage unit that has been used before after the monitoring unit detects that the line using the newly used medium has been established. Before the second blocking unit cuts off the line by the medium, the wireless storage unit for temporarily storing the signal received by the wireless receiving unit, the wired storage unit and the wireless storage unit Based on the temporarily stored signal, and configured to include an estimating unit for estimating the original signal, from either of the two communication stations can instruct the other to switch the line,
The line can be switched without any instantaneous interruption, and there is an effect that loss of data is prevented without specifying the execution time of switching from one to the other communication station.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a communication system according to a first embodiment of the present invention.

FIG. 2 is a flow diagram showing a processing flow by the communication system shown in FIG.

FIG. 3 is a block diagram showing a communication system according to a second embodiment of the present invention.

4 is a flow diagram showing a processing flow by the communication system shown in FIG.

FIG. 5 is a block diagram showing a communication system according to a third embodiment of the present invention.

6 is a flow diagram showing a processing flow by the communication system shown in FIG.

FIG. 7 is a schematic diagram showing a conventional technology and a communication system to which the present invention is applied.

FIG. 8 is a block diagram showing a conventional communication system.

[Explanation of symbols]

1 communication station (first communication station, second communication station), 11 data transmission / reception section (transmission control section), 12 wired / wireless line switching section (blocking section, first blocking section, second blocking section) , 13
Wired synchronization establishing unit, 14 Wireless synchronization establishing unit, 15
Used line monitoring unit (monitoring unit, first monitoring unit, second monitoring unit), 16 wired transmitting / receiving unit (wired transmitting unit, wired receiving unit), 17 wireless transmitting / receiving unit (wireless transmitting unit, wireless receiving unit), 18 Switching execution timing indicating section (second notifying section), 1
9 control signal transmission / reception unit (notification unit, first notification unit, first notified unit, second notified unit), 110 wired reception buffer (wired storage unit), 111 wireless reception buffer ( Wireless storage unit), 112 clock 113 transmission delay measurement unit 2 communication stations (first communication station, second communication station), 2
1 data transmission / reception unit (transmission control unit), 22 wired / wireless line switching unit (blocking unit, first blocking unit, second blocking unit), 2
3 wired synchronization establishing section, 24 wireless synchronization establishing section,
25 used line monitoring unit (monitoring unit, first monitoring unit, second monitoring unit), 26 wired transmitting / receiving unit (wired transmitting unit, wired receiving unit), 27 wireless transmitting / receiving unit (wireless transmitting unit, wireless receiving unit), 28 switching execution timing indicating section (second notifying section), 2
9 Control signal transmission / reception unit (notification unit, first notification unit, first notified unit, second notified unit), 210 wired reception buffer (wired storage unit), 211 wireless reception buffer (wireless Storage section), 212 clock 213 transmission delay measuring section 3 wired transmission path (wired medium), 4 wireless transmission path (wireless medium), CO11 wired / wireless switching signal, CO1
2 control signal, CO13 control signal, CO14 synchronization establishment status signal, CO15 synchronization establishment status signal, CO16 line monitoring signal, CO17 switching execution instruction signal, CO1
8 Switching execution timing instruction signal, DA11 transmission / reception data,
DA12 wired transmission / reception data, DA13 wireless transmission / reception data, CO21 wired / wireless switching signal, CO22 control signal, CO23 control signal, CO24 synchronization establishment state signal, CO25 synchronization establishment state signal, CO26 line monitoring signal, CO27 switching execution instruction signal, CO28 Switching timing signal, DA21 transmission / reception data, DA22
Wired transmission / reception data, DA23 wireless transmission / reception data.

Claims (15)

[Claims] A wireless transmission unit capable of transmitting to a communication station of the other party using a wireless medium; a wired transmission unit capable of transmitting to the communication station of the other party using a wired medium; A first notification unit for notifying the communication station of the other party of a newly used medium, and monitoring whether a line from the communication station of the other party to the own station via the newly used medium is established. A monitoring unit that performs communication with the communication station of the other party after the monitoring unit detects that the line using the newly used medium has been established. A second notifying unit for notifying a communication station, and a blocking unit for cutting off a line using a medium that has been used before after the monitoring unit detects that the line using the newly used medium has been established. Communication station with. 2. The communication device according to claim 1, wherein a time at which the interruption unit interrupts communication using the medium used previously and a time at which the second notification unit notifies the other communication station are simultaneous. The communication station according to 1. 3. A transmission delay measuring section for measuring a transmission delay with a communication station of the other party, wherein the second notifying section makes the second notification section clearer than the time when the blocking section cuts off the communication by the medium used before. 2. The communication station according to claim 1, wherein the notification to the communication station is delayed by the delay. 4. A wireless receiving unit capable of receiving from a communication station of the other party via a wireless medium, a wired receiving unit capable of receiving from the communication station of the other party via a wired medium, A first notified unit that notifies a medium to be used from the communication station of the other party; and a second notification unit that notifies the communication station of the other party of a time when the line using the medium that has been used before should be cut off. A communication station comprising: a notified unit; and a cutoff unit that cuts off a line using a previously used medium at the above time. 5. A wireless receiving unit capable of receiving from a communication station of the other party via a wireless medium, a wired receiving unit capable of receiving from a communication station of the other party via a wired medium, A transmission delay measuring unit for measuring a transmission delay with the communication station; a first notified unit notified of the newly used medium from the communication station of the other party; and a previously notified medium from the communication station of the other party. A second notified unit for notifying the time when the line using the medium has been cut off, and a cut-off unit for cutting off the line using the medium used previously at the time later than the above-mentioned time by the delay. Communication station equipped. 6. A communication station capable of using a line using a wireless medium and a line using a wired medium notifies a communication station of the other side of a newly used medium, and a line using the newly used medium is established. After detecting that the line using the newly used medium has been established, the communication station of the other party informs the communication station of the other party of the time when the communication station of the other party should cut off the line of the previously used medium. A communication switching method, comprising: notifying, and detecting, after detecting that the line using the newly used medium has been established, the line using the previously used medium. 7. A communication station that can use a line using a wireless medium and a line using a wired medium is notified of a newly used medium from a communication station of the other party, and the communication station of the other party has previously used the medium. A communication switching method, wherein a time when a line using a medium that has been used should be cut off is notified, and a line using a medium that has been used before is cut off at the time. 8. A wireless transmission unit comprising a first communication station and a second communication station, wherein the first communication station is capable of transmitting to the second communication station using a wireless medium. A wired transmission unit capable of transmitting to the second communication station using a wired medium, a first notification unit for notifying the second communication station of a newly used medium, A monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium is established, and a monitoring unit that establishes a line using the newly used medium. A second notification unit for notifying the second communication station of a time at which the second communication station should cut off a line using the medium that has been used before, and the newly used medium. Was used before after the monitoring unit detected that the line was established by A first blocking unit for blocking a line by a body, wherein the second communication station is capable of receiving from the first communication station via a wireless medium; A first receiving unit for notifying a newly used medium from the first communication station; a wired receiving unit capable of receiving from the first communication station via a wired medium; A second notified unit for notifying the communication station of a time when the line using the previously used medium should be cut off, and a second cutoff unit for cutting off the line using the previously used medium at the above time A communication system comprising: 9. A wireless transmission unit comprising a first communication station and a second communication station, wherein the first communication station is capable of transmitting to the second communication station using a wireless medium. A wired transmission unit capable of transmitting to the second communication station using a wired medium, a first notification unit for notifying the second communication station of a newly used medium, A monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium is established, and a monitoring unit that establishes a line using the newly used medium. A second notification unit for notifying the second communication station of a time at which the second communication station should cut off a line using the medium that has been used before, and the newly used medium. Was used before after the monitoring unit detected that the line was established by A first blocking unit for blocking a line by a body, a wireless receiving unit capable of receiving from the second communication station via a wireless medium, and performing a reception from the second communication station via a wired medium A first receiving unit for notifying a newly used medium from the second communication station; and a medium previously used from the second communication station. A second notified unit for notifying a time when the line should be cut off, and a second cutoff unit for cutting off the line using the medium used previously at the time, the second communication station However, a wireless transmission unit capable of transmitting to the first communication station using a wireless medium, a wired transmission unit capable of performing transmission to the first communication station using a wired medium, A first notification unit for notifying the first communication station of a newly used medium; A monitoring unit that monitors whether a line from the first communication station to the own station via the newly used medium is established; and a monitoring unit that monitors that a line using the newly used medium is established. A second notifying unit for notifying the first communication station of a time at which the first communication station should cut off a line using a medium that has been used before, after the unit has detected the signal, and After the monitoring unit detects that the line using the medium has been established, a first blocking unit that cuts off the line using the medium that has been used before, and receives from the first communication station via the wireless medium. A wireless receiving unit capable of receiving data from the first communication station via a wired medium; and a second receiving unit notified of a newly used medium from the first communication station. 1 notified unit and the first communication station, Communication unit comprising: a second notified unit that is notified of a time when a line using a medium used in a network should be cut off; system. 10. A wireless transmission unit capable of transmitting to a communication station of the other party using a wireless medium, a wired transmission unit capable of transmitting to the communication station of the other party using a wired medium, A notifying unit that notifies the newly used medium to the communication station of the other party; and a monitoring unit that monitors whether a line from the communication station of the other party to the own station via the newly used medium is established. And after the monitoring unit detects that the line using the newly used medium has been established, a blocking unit that cuts off the line using the previously used medium; and a line using the newly used medium. The wireless transmission unit and the wired transmission unit originate in the same data unit after the monitoring unit detects that the wireless communication unit has been established and before the interruption unit interrupts the line using the previously used medium. Signal it To send is, a communication station that includes a transmission control unit for controlling the radio transmission unit and the wired transmitting unit. 11. A wireless receiving unit capable of receiving from a communication station of the other party via a wireless medium, a wired receiving unit capable of receiving from a communication station of the other party via a wired medium, A notified unit for notifying the medium to be used from the communication station of the other party; and a monitoring unit for monitoring whether a line from the communication station of the other party to the own station via the newly used medium is established. And after the monitoring unit detects that the line has been established, the interruption unit that interrupts the line using the medium that has been used previously, and that the line that has been newly used has been established A wire storing unit for temporarily storing a signal received by the wire receiving unit after the monitoring unit detects and before the blocking unit cuts off the line using the previously used medium; Media used for After the monitoring unit detects that the line has been established, the signal received by the wireless receiving unit is temporarily stored before the blocking unit cuts off the line using the previously used medium. A communication station, comprising: a wireless storage unit that performs an operation; and an estimating unit that estimates an original signal based on the signal temporarily stored in the wired storage unit and the wireless storage unit. 12. A communication station capable of using a line using a wireless medium and a line using a wired medium notifies a communication station of the other party of a newly used medium, and the line using the newly used medium is established. After detecting that the line using the newly used medium has been established, the line using the previously used medium is cut off, and the line using the newly used medium is established. After detecting that, before interrupting the line using the previously used medium, it is necessary to transmit a signal originating from the same data unit using the line using the wireless medium and the line using the wired medium, respectively. Characteristic communication switching method. 13. A communication station that can use a line using a wireless medium and a line using a wired medium is notified of a newly used medium from a communication station on the other side, and a line using the newly used medium is established. After detecting that the line using the newly used medium has been established, the line using the previously used medium is cut off, and the line using the newly used medium is established. After the monitoring unit detects that the signal has been received from the wired medium, and temporarily disconnects the line using the previously used medium, After the monitoring unit detects that the line has been established, the signal received from the wireless medium is temporarily stored and temporarily stored before the line using the previously used medium is cut off. Communication switching method, characterized in that on the basis of the said signal, to estimate the original signal. 14. A wireless transmission unit comprising a first communication station and a second communication station, wherein the first communication station can transmit to the second communication station using a wireless medium. A wired transmission unit capable of transmitting to the second communication station using a wired medium; a notification unit for notifying the second communication station of a newly used medium; and a second communication. A first monitoring unit that monitors whether a line from the station to the own station via the newly used medium is established, and a first monitoring unit that detects that the line has been established. A first blocking unit that cuts off a line using the medium that has been used, and a line that uses the medium that has been used before after the monitoring unit detects that the line that uses the newly used medium has been established. Before the first blocking unit blocks the wireless transmission unit and the wired transmission unit. The wireless communication unit and the transmission control unit controlling the wired transmission unit so that the units transmit signals originating from the same data unit, respectively. A wireless receiving unit capable of receiving from a station via a wireless medium; a wired receiving unit capable of receiving from the first communication station via a wired medium; A notified unit notified from one communication station; a second monitoring unit that monitors whether a line from the first communication station to the own station via the newly used medium is established; After the monitoring unit detects that the line has been established, a second interruption unit that interrupts the line using the medium that has been used previously, and a second interruption unit that disconnects the line using the newly used medium. After detection by the monitoring unit, Before the second blocking unit cuts off the line using the medium that has been set, the wire storing unit that temporarily stores the signal received by the wire receiving unit, and the line that uses the newly used medium are connected. After the monitoring unit detects that the connection has been established, the signal received by the wireless receiving unit is temporarily stored before the second blocking unit cuts off the line using the previously used medium. A communication system comprising: a wireless storage unit configured to perform the above operation; and an estimation unit configured to estimate an original signal based on the signal temporarily stored in the wired storage unit and the wireless storage unit. 15. A wireless transmission unit comprising a first communication station and a second communication station, wherein the first communication station is capable of transmitting to the second communication station using a wireless medium. A wired transmitting unit capable of transmitting to the second communication station using a wired medium; a notifying unit for notifying the second communication station of a medium to be newly used; A first monitoring unit that monitors whether a line from a station to the own station via the newly used medium is established; and a monitoring unit that establishes a line using the newly used medium. A first blocking unit that cuts off a line using a medium that has been used before, and a monitoring unit that detects that a line using a medium that is newly used has been established. Before the first blocking unit cuts off the line by the medium used, A transmission control unit that controls the wireless transmission unit and the wired transmission unit so that the wireless transmission unit and the wired transmission unit respectively transmit signals originating from the same data unit; and a wireless medium from the second communication station. A wireless receiving unit capable of receiving data via the second communication station, a wired receiving unit capable of receiving data via the wired medium from the second communication station, and a medium newly used by the second communication station. A notification unit notified from the second communication station; a second monitoring unit that monitors whether a line from the second communication station to the own station via the newly used medium is established; After the monitoring unit detects that the communication has been performed, the second blocking unit that cuts off the line using the previously used medium, and the monitoring unit detects that the line using the newly used medium has been established. After detecting, it is used before Before the second cutoff unit cuts off the line by the used medium, the wire storage unit for temporarily storing the signal received by the wire reception unit, and the line by the newly used medium are established. After the monitoring unit detects that the signal has been received by the wireless receiving unit before the second blocking unit cuts off the line using the previously used medium. Storage unit; and an estimator for estimating an original signal based on signals temporarily stored in the wired storage unit and the wireless storage unit. A wireless transmission unit capable of transmitting to the first communication station using a wireless medium, a wired transmission unit capable of performing transmission to the first communication station using a wired medium, A notifying unit for notifying the first communication station of a medium used for A first monitoring unit that monitors whether a line from the first communication station to the own station via the newly used medium is established, and that a line using the newly used medium is established. After the monitoring unit detects, the first blocking unit that cuts off the line using the medium that has been used previously, and after the monitoring unit detects that the line that uses the newly used medium has been established The wireless transmission unit and the wired transmission unit transmit signals originating from the same data unit before the first interruption unit interrupts the line using the previously used medium, respectively. A transmission unit that controls the transmission unit and the wired transmission unit; a wireless reception unit that can receive from the first communication station via a wireless medium; and a reception unit that receives from the first communication station via a wired medium. Can do wired A receiving unit, a notified unit for notifying the newly used medium from the first communication station, and a line from the first communication station to the own station via the newly used medium is established. A second monitoring unit that monitors whether or not a line using a medium that has been used previously is shut off after the monitoring unit detects that a line using a medium that is newly used has been established. After the monitoring unit detects that the line using the newly used medium has been established, and before the second blocking unit cuts off the line using the previously used medium. A wire storage unit for temporarily storing a signal received by the wire reception unit, and a wire storage unit that is used before and after the monitoring unit detects that a line with the newly used medium has been established. The second cutoff of the line by the medium Before shutting off, a wireless storage unit for temporarily storing the signal received by the wireless receiving unit, based on the signal temporarily stored in the wired storage unit and the wireless storage unit, A communication system comprising: an estimation unit configured to estimate an original signal.