JPH10112884A - Data link setup method, interruption method and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely and quickly set up and interrupt a data link by using a transmission frame by which a transmission timing is confirmed in the transmission reception for confirmation with respect to a setup request or an interrupt request. SOLUTION: A data link setup request side sends repetitively a plurality of 1st transmission frames F1 including different setup request numbers Req-1 to Req-6 to a setup requested side. Upon the receipt of the transmission frame F1, the setup requested side sends a transmission frame F2 including setup acknowledge numbers Ack-1 to Ack-6 corresponding to the setup request numbers Req-1 to Req-6. Upon the receipt of the transmission frame F2, the setup request side sends repetitively a transmission frame F3 including a flag FwCh denoting the understanding of the setup acknowledge numbers Ack-1 to Ack-6 till its own transmission timing, and the setup requested side uses the timing when the transmission frame F3 at first for its own data transmission timing. Thus, a round tip delay required for re-transmission control of an error frame is acquired simultaneously by both the parties when the link is set up so as to set up the link quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for establishing and disconnecting a data link in communication using a wireless transmission path or another transmission path with variable transmission quality.

[0002]

2. Description of the Related Art In communication including a wireless transmission path (wireless section) between communication apparatuses, the transmission quality is generally lower than that of an ISDN or other wired transmission path, and propagation between a base station and a mobile station is difficult. Transmission quality changes greatly depending on the environment and the like.

In a wireless transmission path, the transmission quality may be degraded to a bit error rate (BER) of about 0.3%. In such a case, a frame indicating a request or confirmation of data link establishment is continuously generated. It may be wrong.

FIGS. 6 and 7 show an example of a frame configuration at the time of establishing a data link used in conventional wireless communication. FIG. 6 is a diagram showing an example of a conventional synchronous frame configuration, and FIG. 7 is a diagram showing an example of a conventional control frame configuration. FIG. 8 is a diagram showing a procedure for establishing a data link used in a conventional wireless communication.

In the conventional data link establishment procedure shown in FIG. 8, the request side repeatedly transmits a synchronization request for data link establishment using the synchronization frame shown in FIG. 6, and the requested side responds to the synchronization request. After the synchronization confirmation is repeatedly transmitted and the requesting side receives the synchronization confirmation, after requesting and confirming the round trip delay and other control information necessary for the error frame retransmission control using the control frame shown in FIG. Establish a data link.

FIG. 9 is a diagram showing a conventional data link disconnection procedure. The transmission frame used for the data link disconnection procedure has the same configuration as the synchronization frame shown in FIG. 6, and the “data link establishment request number” portion becomes the “data link disconnection request number” and the “data link establishment confirmation The “number” part is the “data link disconnection confirmation number”. In FIG. 9, the disconnection request side transmits a disconnection request to the disconnection request side, and when the disconnection request side receives the disconnection request, the disconnection request side repeatedly transmits disconnection confirmation to the disconnection request side for a certain number of times. The disconnection requesting side disconnects the data link when receiving the disconnection confirmation.

[0007]

In such a conventional data link establishment method, as described above, a synchronization request for establishing a data link is repeatedly transmitted from the establishment request side, and the establishment request side synchronizes with the synchronization request. The confirmation request is repeatedly transmitted, and after the establishment request side receives the synchronization confirmation, it requests and confirms the round trip delay and other control information, and then establishes a bidirectional data link until data transmission becomes possible. The time gets longer.

In the conventional data link disconnection method,
Since the transmission quality of the wireless transmission path is degraded and the disconnection request and disconnection confirmation may be erroneous, it is necessary to repeat transmission of disconnection confirmation a certain number of times. Therefore, there is a case where the data link cannot be disconnected even though the data communication has been completed on both the disconnect request side and the disconnected request side.

SUMMARY OF THE INVENTION The present invention has been made in view of such a background, and provides a data link establishment method, a disconnection method, and a control method capable of reliably and quickly establishing and disconnecting a data link in a wireless transmission path. The purpose is to provide. An object of the present invention is to provide a data link establishment method, a disconnection method, and a control method that can effectively use radio waves. An object of the present invention is to provide a data link establishment method, a disconnection method, and a control method suitable for a wireless communication system.

[0010]

SUMMARY OF THE INVENTION A first aspect of the present invention is a data link establishing method for transmitting and receiving a transmission frame prior to bidirectional data communication between communication devices including a wireless section to establish a data link. Data link establishment method.

Here, a feature of the present invention is that the data link establishment request side repeatedly transmits a plurality of first transmission frames each including a different establishment request number to the establishment request side. Upon receiving the first transmission frame, the establishment request side transmits a plurality of second transmission frames each including an establishment request number included in each transmission frame and an establishment confirmation number corresponding to the establishment request number, When the establishment request side receives the second transmission frame, a plurality of third transmission frames each writing a flag indicating an acknowledgment for the establishment confirmation number instead of the establishment request number included in the transmission frame Is repeatedly transmitted until its own data transmission timing, and the established request side determines its own reception timing of this third transmission frame by its own timing. There is in the place where the over data transmission timing.

Further, the establishment request side determines a time difference from a transmission timing of the first transmission frame to a reception timing of the second transmission frame having an establishment confirmation number corresponding to the establishment request number of the transmission frame. Measure,
This measurement result is stored as a reference for retransmission control, and the establishment request side determines from the transmission timing of the second transmission frame a third flag having a flag corresponding to the establishment confirmation number of the transmission frame. It is desirable to measure a time difference up to the reception timing of the transmission frame and store the measurement result as a reference for retransmission control.

Thus, by transmitting and receiving a transmission frame for establishing a data link, a data link can be established without transmitting and receiving a control frame.

That is, a round trip delay can be measured by receiving a transmission frame returned in response to a transmission frame transmitted by itself and measuring the time from transmission to reception. Therefore, a data link can be reliably and quickly established without using a control frame for notifying a run trip delay.

[0015] A second aspect of the present invention is a data link disconnection method for transmitting and receiving a transmission frame and disconnecting a data link prior to termination of bidirectional data communication between communication devices including a wireless section. Is the way.

Here, a feature of the present invention is that the disconnection request side of the data link repeatedly transmits a plurality of fourth transmission frames each including a different disconnection request number to the disconnection request side. Upon receiving the fourth transmission frame, the disconnection request side repeatedly transmits a plurality of fifth transmission frames each including a disconnection request number included in each transmission frame and a disconnection confirmation number corresponding to the disconnection request number. Upon receiving the fifth transmission frame, the disconnection request side writes a plurality of sixth transmission flags each indicating a flag indicating acknowledgment for the disconnection confirmation number in place of the disconnection request number included in the transmission frame. Repeatedly transmit the frame until the set transmission end timing,
The disconnection request side uses the timing at which the first sixth transmission frame is received as its own transmission end timing.

As described above, by transmitting and receiving the transmission frame for disconnecting the data link, the data link can be disconnected.

That is, by receiving a transmission frame returned in response to a transmission frame transmitted by itself,
Data links can be reliably and quickly disconnected.
At this time, even if the transmission quality of the wireless transmission path is degraded, it is possible to know that the other party will end transmission by receiving any one of the repeatedly transmitted transmission frames. The data link can be disconnected quickly.

Alternatively, the disconnection requesting side may end the transmission when the fifth transmission frame cannot be received even after a certain time has elapsed after transmitting the fourth transmission frame. And the disconnection request side,
After the fifth transmission frame is transmitted, the transmission may be terminated when the sixth transmission frame cannot be received after a certain period of time.

As a result, even if the transmission quality of the wireless transmission path is greatly degraded and it is difficult to receive the transmission frame, the data link can be reliably and promptly disconnected.

A third aspect of the present invention is a data link control method for controlling establishment and disconnection of a data link for two-way data communication between communication devices including a wireless section. .

Here, a feature of the present invention resides in that the establishment and disconnection of a data link are controlled by the data link establishment method or the data link disconnection method.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION

[0024]

【Example】

(First Embodiment) A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a wireless communication system to which the first embodiment of the present invention is applied. FIG. 2 is a diagram showing the configuration of the synchronization establishment frame according to the first embodiment of the present invention. FIG. 3 is a diagram showing a data link establishment procedure according to the first embodiment of the present invention. FIG.
FIG. 4 is a diagram showing a data link disconnection procedure according to the first embodiment of the present invention.

The present invention relates to a data establishing method for transmitting and receiving a transmission frame as shown in FIG. 2 prior to bidirectional data communication between communication devices 1 and 2 including a radio section as shown in FIG. This is a data link establishment method for establishing data links L1 and L2.

Here, it is a feature of the present invention that the data link establishment request side transmits a plurality of first transmission frames including different establishment request numbers Req-1 to Req-6 to the establishment request side. 3 is transmitted repeatedly, and upon receiving the transmission frame F1, the established request side receives the transmission frame F1.
As a plurality of second transmission frames including the establishment request numbers Req-1 to Req-6 and the establishment confirmation numbers Ack-1 to Ack-6 corresponding to the establishment request numbers Req-1 to Req-6, respectively. The transmission frame F2 shown in FIG. 3 is transmitted, and the establishment request side transmits the transmission frame F2.
When receiving No. 2, the flag Fw indicating acknowledgment for the establishment confirmation numbers Ack-1 to Ack-6 instead of the establishment request numbers Req-1 to Req-6 included in the transmission frame F2
The transmission frame F3 shown in FIG. 3 as a plurality of third transmission frames in which Ch-OK is written is repeatedly transmitted until its own data transmission timing, and the establishment request side receives this transmission frame F3 first. This timing is used as its own data transmission timing.

From the transmission timing of the transmission frame F1, the establishment request side determines the establishment confirmation number Ac corresponding to the establishment request numbers Req-1 to Req-6 of the transmission frame F1.
The time difference until the reception timing of the transmission frame F2 having k-1 to Ack-6 is measured, and the measurement result is stored as a reference for retransmission control, and the established request side transmits the transmission frame F2. From the timing, the transmission frame F3 having the flag FwCh-OK corresponding to the establishment confirmation numbers Ack-1 to Ack-6 of the transmission frame F2
Is measured, and the measurement result is stored as a reference for retransmission control.

As shown in FIG. 4, the data link disconnection request side transmits a plurality of fourth transmission frames including different disconnection request numbers Req-1 to Req-6 to the disconnection request side. Upon receiving the transmission frame F4, the disconnection request side receives the transmission frame F4, and the disconnection request numbers Req-1 to Req-6 and the disconnection request numbers Req-6 included in each of the transmission frames F4.
disconnection confirmation number Ack-1 corresponding to q-1 to Req-6
To Ack-6, the transmission frame F5 as a plurality of fifth transmission frames is repeatedly transmitted. When the disconnection request side receives the transmission frame F5, the disconnection request number Req- 1 to R
disconnection confirmation numbers Ack-1 to Ack-6 instead of eq-6
The transmission frame F6 as the sixth transmission frame in which the flag FwCh-OK indicating the acknowledgment of the first transmission frame F6 is written is repeatedly transmitted until the set transmission end timing.
Is received as its own transmission end timing.

The first embodiment of the present invention will be described in more detail. Each transmission frame uses the frame format shown in FIG. Here, the frame type “Open”
Indicates the request and confirmation when establishing the data link,
“Close” indicates a request and confirmation when the data link is disconnected.

In the first embodiment of the present invention, "Open" is defined as a link setting of a transmission channel (a reception channel when viewed from the other party) when viewed from the own apparatus. This is because in the case of two-way communication, it is necessary to establish an independent link for transmission of each of the establishment request side and the establishment request side.

In FIG. 3, F1 is a transmission frame for a data link establishment request issued by the establishment request side,
Data link establishment request numbers Req-1 to Req-6 are written and transmitted. F2 is a transmission frame in which the data link establishment request issued by the establishment request side and the establishment confirmation are piggybacked, and the data link establishment request numbers Req-1 to Req.
q-6 and establishment confirmation numbers Ack-1 to Ack-6 are written and transmitted.

The procedure for establishing a data link according to the first embodiment of the present invention will be described below with reference to timing. At the timing T1, the establishment request side transmits the transmission frame F1 in which the data link establishment request numbers Req-1 to Req-6 are written, and the establishment request side transmits the data link establishment request number Re
After receiving the transmission frame F1 in which q-1 to q-6 has been written, at timing T2, the data link establishment request numbers Req-1 to Req-6 and the data link establishment confirmation numbers Ack-1 to Ack-1 from the establishment request side. The transmission frame F2 in which Ack-6 is written is transmitted.

At the timing T3, the establishment request side establishes the confirmation number A for the transmission frame F1 (establishment request numbers Req-1 to Req-6) transmitted at the timing T1.
The transmission frame F in which ck-1 to Ack-6 and the establishment request numbers Req-1 to Req-6 from the establishment request side are written.
2 and a flag FwCh-OK indicating that the confirmation of the establishment of the data link requested at the timing T4 has been acknowledged, and the establishment of the data link establishment requests (establishment request numbers Req-1 to Req-6) from the establishment request side. The transmission frame F3 in which the confirmation (establishment confirmation numbers Ack-1 to Ack-6) is written is transmitted.

At timing T5, the establishment request side confirms the establishment of the data link of the transmission channel (establishment confirmation numbers Ack-1 to Ack-6) as seen from its own device and the reception channel as seen from its own device, ie, from the partner device A flag FwCh-OK indicating that the partner device has acknowledged the establishment of the data link of the transmission channel at the timing T5 '
Is recognized by the received transmission frame F3, and it is determined that a bidirectional data link has been established. Therefore, data transmission is started from timing T5.

At timing T6 ', the establishment request side has received the data link establishment confirmation (establishment confirmation numbers Ack-1 to Ack-6) of the transmission channel as seen from the own apparatus, and the transmission side channel is usable. , The flag FwCh-O indicating that the partner device has acknowledged the confirmation of the establishment of the data link of the transmission channel.
K has not been received. However, at timing T6 ', the establishment request side has received the information frame FD1, and the partner apparatus has started data transmission after confirming the establishment of the data link on the transmission / reception channel. The data transmission is started from the timing T6 when the information frame FD1 is received also from the establishment request side.

Each of the transmission frames F1 to F3 for requesting or confirming the establishment of the data link has an establishment request number and / or an establishment confirmation number, and the establishment request side establishes the request numbers Req-1 to Req-6 at timing T1.
Is transmitted and the transmission frame F2 including the establishment confirmation numbers Ack-1 to Ack-6 for the establishment request numbers Req-1 to Req-6 is received at the timing T3, so that the retransmission control of the error frame is performed. Can be measured by (timing T3)-(timing T1). Similarly, the established request side can measure the round trip delay by (timing T5 ')-(timing T2).

FIG. 4 is a diagram showing a data link disconnection sequence according to the first embodiment of the present invention. In FIG. 4, F4 is a transmission frame for a data link disconnection request issued by the disconnection request side, and has a data link disconnection request number Req-
1 to Req-6 are written and transmitted. F5 is a transmission frame in which the data link disconnection request issued by the disconnection request side and the disconnection confirmation are piggybacked, and the disconnection request number Req-1
To Req-6 and the disconnection confirmation numbers Ack-1 to Ack-6 are written and transmitted.

At timing T1, the disconnection request side transmits the transmission frame F4 in which the data link disconnection request numbers Req-1 to Req-6 are written, and the disconnection request side transmits the data link disconnection request numbers Req-1 to Req-. 6 after receiving the transmission frame F4 in which the data link 6 has been written, at timing T2, a data link disconnection request (disconnection request number Req-1 to Req-6) from the disconnection request side and disconnection confirmation (disconnection confirmation number A)
ck-1 to Ack-6) are transmitted to transmit the transmission frame F5.

At the timing T3, the disconnection request side receives the disconnection confirmation number A for the transmission frame F4 (disconnection request numbers Req-1 to Req-6) transmitted at the timing T1.
The transmission frame F5 in which the ck-1 to Ack-6 and the data link disconnection requests Req-1 to Req-6 from the disconnection request side are written is received, and the confirmation of the disconnection of the data link requested at the timing T4 is acknowledged. FwCh indicating that
-Transmit the transmission frame F6 in which the disconnection confirmation (disconnection confirmation numbers Ack-1 to Ack-6) for the data link disconnection requests (disconnection request numbers Req-1 to Req-6) from the disconnection request side are written. .

At timing T5, the disconnection request side confirms the disconnection of the data link of the transmission channel (disconnection confirmation numbers Ack-1 to Ack-6) as seen from the own device and the reception channel as seen from the own device, that is, from the partner device. The flag FwCh-OK indicating that the other device has acknowledged the disconnection confirmation of the data link of the transmission channel is recognized by the transmission frame F5 received at the timing T5 ', and it is determined that the bidirectional data link can be disconnected. Therefore, the transmission of the data is terminated from the timing T5, and the data link disconnection process is performed.

At the disconnection request side, at the timing T6 ', the data link disconnection confirmation (disconnection confirmation numbers Ack-1 to Ack-6) of the transmission channel viewed from the own device has been received.
Although the transmission side channel can be disconnected, the reception side channel disconnection confirmation, that is, a flag FwCh- indicating that the other device has acknowledged the transmission channel data link disconnection confirmation.
OK has not been received. However, after the timing T6 ', the disconnection request side has not received the transmission frame, and the partner apparatus has confirmed the disconnection of the data link on the transmission / reception channel, and has finished the data transmission. The transmission of data is terminated from timing T6 upon termination of reception of F5, and data link disconnection processing is performed.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a diagram showing a data link disconnection sequence according to the second embodiment of the present invention. At the timing T1 in FIG. 5, the disconnection request side transmits the frame F7 in which the data link disconnection request numbers Req-1 to Req-6 are written, and the disconnection request side transmits the data link disconnection request number Re.
After receiving the transmission frame F7 in which q-1 to Req-6 are written, at timing T2, a data link disconnection request (disconnection request number Req-1 to Req-
6) and disconnection confirmation (disconnection confirmation number Ack-1 to Ack-
The transmission frame F8 in which 6) is written is transmitted.

At the timing T3, the disconnection request side receives the disconnection confirmation numbers (Ack-1 to Ack-6) for the transmission frame F7 (disconnection request numbers Req-1 to Req-6) transmitted at the timing T1, and transmits the information from the disconnection request side. Data link disconnection request (disconnection request number Req-1 to Req-
Since the transmission frame F8 in which 6) has been written cannot be repeatedly received normally, the transmission of the transmission frame is terminated and the data link disconnection process is performed at the timing T6 after the lapse of the predetermined time Tm1.

At the timing T5, the disconnection request side confirms the disconnection of the data link of the transmission channel (disconnection confirmation numbers Ack-1 to Ack-6) as seen from its own device and the reception channel as seen from its own device, that is, from the partner device. The flag FwCh-OK indicating that the other device has acknowledged the disconnection confirmation of the data link of the transmission channel of No. cannot be normally received, and after a lapse of a predetermined time Tm2, the transmission of the transmission frame is terminated from the timing T5 and the data link is terminated. Perform disconnection processing.

As a result, even if the transmission quality of the wireless transmission path is greatly degraded and it is difficult to receive the transmission frame F8, the data link can be reliably and promptly disconnected.

(Summary of Embodiment) According to the embodiment of the present invention,
Even when a bursty error exists in the transmission line, the data link can be quickly and reliably established or disconnected.

That is, the transmission frame used for the request and confirmation of the data link establishment includes not only the flag for identifying whether the request is the request or the confirmation, but also the number indicating the request timing of the data link establishment and the data link transmitted at which timing. By using a frame with a number field indicating whether to confirm the establishment request, the round trip delay required for retransmission control of an error frame in data communication can be obtained at the same time in both directions when the link is established. Therefore, a data link can be quickly and reliably established even when a bursty error exists in the transmission path.

In particular, when bidirectional data communication is performed by a wireless transmission path, a reliable negotiation can be taken and this is effective.

Further, when the data link disconnection request cannot be confirmed when the data link is disconnected, the data link can be quickly and reliably disconnected.

[0050]

As described above, according to the present invention,
Establishing and disconnecting a data link in a wireless transmission path can be performed reliably and quickly. Therefore, radio waves can be used effectively.

According to the present invention, a data link establishment method, a disconnection method, and a control method suitable for a wireless communication system can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a wireless communication system to which a first embodiment of the present invention is applied.

FIG. 2 is a diagram showing a configuration of a synchronization establishment frame according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a data link establishment procedure according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a data link disconnection procedure according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a data link disconnection sequence according to the second embodiment of the present invention.

FIG. 6 is a diagram showing a configuration example of a synchronization frame according to a conventional example.

FIG. 7 is a diagram showing a control frame configuration example of a conventional example.

FIG. 8 is a diagram showing a procedure for establishing a data link used in wireless communication of a conventional example.

FIG. 9 is a diagram showing a data link disconnection procedure of a conventional example.

[Explanation of symbols]

 1, 2 Communication device Ack-1 to Ack-6 Confirmation number F1 to F8 Transmission frame FD1, FD2 Information frame FwCh-OK flag L1, L2 Data link Req-1 to Req-6 Request number T1 to T6, T5 ', T6 ′ Timing

Claims (6)

[Claims] 1. A data link establishment method for transmitting and receiving a transmission frame and establishing a data link prior to two-way data communication between communication devices including a wireless section, wherein a data link establishment request side is transmitted to an establishment request side. On the other hand, a plurality of first transmission frames each including a different establishment request number are repeatedly transmitted.When the establishment request side receives the first transmission frame, the establishment request side includes the establishment request number included in each transmission frame and its establishment. A plurality of second transmission frames each including an establishment confirmation number corresponding to the request number are transmitted.When the establishment request side receives the second transmission frame, the establishment request side replaces the establishment request number included in the transmission frame. The plurality of third transmission frames in which flags indicating the acknowledgment of the establishment confirmation number have been written by the The data link establishment method characterized in that the established request side uses the timing at which the third transmission frame was first received as its own data transmission timing. 2. The establishment request side determines a time difference from a transmission timing of the first transmission frame to a reception timing of the second transmission frame having an establishment confirmation number corresponding to the establishment request number of the transmission frame. Measure and store this measurement result as a reference for retransmission control, and the established request side has a flag corresponding to the establishment confirmation number of the transmission frame from the transmission timing of the second transmission frame. 2. The data link establishment method according to claim 1, wherein a time difference up to a reception timing of the third transmission frame is measured, and the measurement result is stored as a reference for retransmission control. 3. A data link disconnection method for transmitting and receiving a transmission frame and disconnecting a data link prior to terminating bidirectional data communication between communication devices including a wireless section, wherein the data link disconnection request side comprises: Side repeatedly transmits a plurality of fourth transmission frames each including a different disconnection request number, and upon receiving the fourth transmission frame, the disconnected request side receives the disconnection request number and the disconnection request number included in each of the transmission frames. A plurality of fifth transmission frames each including a disconnection confirmation number corresponding to the disconnection request number are repeatedly transmitted.When the disconnection request side receives the fifth transmission frame, the disconnection request side included in the transmission frame is transmitted. A plurality of sixth transmission frames in which flags indicating the acknowledgment of the disconnection confirmation number are respectively written in place of the numbers are transmitted. A data link disconnection method, wherein the transmission request is repeatedly transmitted until an end timing, and the disconnection request side uses the timing at which the first sixth transmission frame is received as its own transmission end timing. 4. The data according to claim 3, wherein the disconnection request side terminates the transmission when the fifth transmission frame cannot be received even after a lapse of a predetermined time after transmitting the fourth transmission frame. Link disconnection method. 5. The transmission method according to claim 3, wherein the disconnected request side terminates the transmission when the sixth transmission frame cannot be received even after a lapse of a predetermined time after transmitting the fifth transmission frame. Data link disconnection method. 6. A data link control method for controlling establishment and disconnection of a data link for two-way data communication between communication devices including a wireless section, according to claim 1 or 2. A data link control method characterized by controlling establishment and disconnection of a data link by the data link disconnection method according to any one of (3) to (5).