JP2001244853A - Controller for communication line retransmission and control method for communication line retransmission used for same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller for communication line retransmission, which can improve the efficiency of a communication line. SOLUTION: If a reception level decreases below a previously set limit after data from data 1 transmitter are received normally at a data receiver, a request to resend is stopped and normal data communication is carried on as it is; even if data 2, data 5 to 7, and data 9 have lost frames, no request to resend is sent from the data receiver, so the data up to data 10 are sent out. When the received level increases above prescribed, the request to resend is restarted by the data receiver, and the data following the data 2 lost first are all requested with a partial resending control reject (REJ) (2) signal, requesting all data to be resent after the lost data, so that the data 2 to 10 are resent. When the quantity of the lost data is small, a selective partial resending control reject (SREJ) signal is sent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication line retransmission control device and a communication line retransmission control method used therefor, and more particularly to a method for retransmitting a lost frame when a frame loss occurs during data reception by a frame configuration.

[0002]

2. Description of the Related Art When data is transmitted between mobile radios or with a base station using a data transmission terminal connected to the mobile radio, the data transmission is performed depending on the line condition accompanying the movement of the mobile radio. The quality may be degraded. For this reason, some conventional mobile radios display the outside / in-service area and the reception electric field level on the display unit in order to display the communication availability.

[0003] In the above-mentioned mobile radio equipment, when the area display or the effective display of the received electric field level is displayed, when a request for data transmission is made, the mobile radio equipment communicates with a base station or another mobile radio equipment in real time in response to the request. A connection is made between them and data transmission is being performed.

[0004] In this case, data transmission is performed even in a state where the data transmission quality may be degraded due to multipath, fading, or the like, so that the data transmission quality frequently degrades. This is because the in-zone display and the effective display of the received electric field level are based on the judgment level of voice communication, and the judgment level is not always the basis for judging the propriety of data transmission.

In the above-mentioned mobile radio, data transmission is possible even when the condition of the communication line is poor. As a result, retransmission of data, disconnection and reconnection of the line are repeated, and traffic increases. Is one of the causes.

[0006] In order to solve the above-mentioned problem, in the technique disclosed in Japanese Patent No. 2871587, an idle signal transmitted from a partner station is received, and based on the idle signal, a received electric field, an error rate, and the like are determined. Is detected, and when the received electric field is equal to or higher than a predetermined level and the error rate is equal to or lower than a certain value, a wireless line is connected to a partner station to perform data transmission.

In the data retransmission described above, for example, as shown in FIG. 5, during reception of data having a frame structure, when the reception level decreases from point A to point D and a frame is lost, a missing frame is generated. As a procedure for requesting only retransmission, only selective partial retransmission control reject (SREJ; Selective Rej) as shown in FIG.
ect).

In FIG. 12, when data 1 is normally received from the data transmitting side on the data receiving side, a missing frame occurs in data 2 and data 3 is normally received, the data receiving side selectively receives the data. A retransmission control reject (2) is sent. Data 2 requested by the data transmission side
Is retransmitted, so that the data receiving side normally receives data 2 and then receives data 4 normally.

The data 5, the data 6, the data 6,
When a missing frame occurs in the data 7 and the data 8 is normally received, the selective retransmission control rejects (5), (6), and (7) are sent from the data receiving side in the same manner as described above. However, when a loss occurs in the selective partial retransmission control rejects (5) and (6), only the data 7 requested by the data transmission side is retransmitted, and the data 9,
Data 10 is transmitted.

At this time, when a missing frame occurs in the data 7 and the data 9, a selective partial retransmission control reject (5) 'which has not reached the data transmitting side is transmitted from the data receiving side. When a missing frame occurs again in the data 5 from the data transmitting side, selective partial retransmission control rejects (6) 'and (7)' are transmitted from the data receiving side. However, if a loss occurs in the selective partial retransmission control reject (6) ', only the data 7 requested by the data transmission side is retransmitted.

When the data 7 is received normally, the selective retransmission control reject (5) ″,
(6) "is transmitted, whereby data 5, data 6
Is received, a selective partial retransmission control reject (9) is sent out. When the data 9 transmitted from the data transmission side is normally received in response to this request, the process ends. In this case, the number of transmission data is 17, and the number of retransmission requests is 10.

As described above, the selective partial retransmission control rejection occurs for all the missing frames, and if the reception level continues to decrease for a long time, a large number of selective partial retransmission control rejects will occur. The traffic in this case is as shown in FIG.

[0013]

In the above-described conventional method of retransmitting a lost frame, a large amount of selective partial retransmission control rejection due to a long-time drop in reception level causes a reduction in use efficiency for a finite communication line. become.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a communication line retransmission control device and a communication line retransmission control method that can solve the above-mentioned problems and improve the use efficiency of communication lines.

[0015]

A communication line retransmission control device according to the present invention is a communication line retransmission control device for retransmitting lost data when data loss occurs during data reception, and comprising: Detecting means for detecting, when the reception level detected by the detection means is lower than a preset retransmission request stop level, stops the data retransmission request and after the stop of the retransmission request the reception level is Retransmission request control means for resuming the retransmission request when the retransmission request suspension level is higher than the retransmission request suspension level, so that normal data communication is continued while the data retransmission request is stopped.

Another communication line retransmission control device according to the present invention is a communication line retransmission control device for controlling retransmission of lost data when data is lost during data reception, and detects a bit error rate of the data. Detecting means for stopping the data retransmission request when the bit error rate detected by the detection means becomes higher than a preset specified value, and for stopping the retransmission request, the bit error rate is higher than the specified value. Retransmission request control means for resuming the retransmission request when the data retransmission request becomes low, so that normal data communication is continued while the data retransmission request is stopped.

A communication line retransmission control method according to the present invention is a communication line retransmission control method for controlling retransmission of lost data when data loss occurs during data reception, wherein a reception level detected from received data is determined in advance. Stopping the data retransmission request when the retransmission request stop level becomes lower than the set retransmission request stop level; and resuming the retransmission request when the reception level becomes higher than the retransmission request stop level after the retransmission request is stopped. And normal data communication is continued while the data retransmission request is stopped.

Another communication line retransmission control method according to the present invention is a communication line retransmission control method for controlling retransmission of lost data when data loss occurs during data reception, wherein a bit error detected from received data is detected. Stopping the data retransmission request when the rate becomes higher than a preset specified value, and resuming the retransmission request when the bit error rate becomes lower than the specified value after stopping the retransmission request. And normal data communication is continued while the data retransmission request is stopped.

That is, the communication line retransmission control method of the present invention is a technique for monitoring a reception level and stopping only a retransmission request when the reception level falls below a specified value. Will be

Thus, it is possible to prevent a large number of retransmission requests for the same signal from being generated by stopping the retransmission request when the reception level becomes equal to or less than the prescribed value.
It is possible to improve the use efficiency of the communication line.

Further, the communication line retransmission control method of the present invention
It is possible to monitor the error bit rate and stop only the retransmission request when the error bit rate falls below the specified value, or to monitor both of them and retransmit when one of them falls below the specified value. It is also possible to stop only the request. Also in this case, it is possible to improve the use efficiency of the communication line.

[0022]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sequence chart showing a retransmission operation according to the embodiment of the present invention.
FIG. 4 is a diagram showing a traffic volume of a retransmission operation according to the embodiment of the present invention. An embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 1, when the data reception side normally receives data 1 from the data transmission side and the reception level falls below a predetermined value, the retransmission request is stopped. Is continued as it is.

That is, in the subsequent data communication, data 2 to data 10 are transmitted from the data transmitting side, but even if missing frames occur in data 2, data 5 to data 7, and data 9, the data receiving side Since the retransmission request is not transmitted from, data 10 is transmitted.

Thereafter, when the reception level becomes equal to or higher than the prescribed value, the retransmission request is restarted on the data receiving side, and a partial retransmission control reject (REJ; Reject) for requesting retransmission of all data after the first lost data is performed. ), All data after the first data 2 which is lost are requested. Therefore, data 2 to data 10 are retransmitted. In this case, the number of transmission data is 19, and the number of retransmission requests is 1. That is, the communication amount at this time is as shown in FIG.

According to the present invention, as described above, while the reception level is low, the issuance of the selective partial retransmission control reject (SREJ) for individually requesting retransmission of lost data is stopped, and after the reception level is restored, the partial retransmission control is rejected. Since the generation is performed, the communication traffic on the communication line is reduced as compared with the case where the selective partial retransmission control reject is issued for each missing frame as in the related art (see FIGS. 12 and 13). The use efficiency of the communication line can be improved. Also, by stopping the transmission of the selective partial retransmission control reject, power consumption can be reduced.

FIG. 3 is a block diagram showing a configuration of a data communication system according to one embodiment of the present invention. In FIG. 3, a data communication system according to one embodiment of the present invention is configured by connecting a data transmitting unit 1 and a data receiving unit 2 via a wireless line.

The data transmission unit 1 includes an antenna 10, a transmission buffer 11, a transmission control unit 12, and a radio transmission unit 13.
And a radio reception unit 14. The data reception unit 2 includes an antenna 20, a radio reception unit 21, a reception data storage control unit 22, a reception buffer 23, a reception level detection unit 24, a retransmission request control It comprises a unit 25 and a wireless transmission unit 26.

In the data transmission unit 1, the transmission buffer 11 stores data to be transmitted from the device to the data reception unit 2, and the transmission control unit 12 transmits the data stored in the transmission buffer 11 to the radio transmission unit 13 and The data is transmitted to the data receiving unit 2 via the antenna 10.

The transmission control unit 12 receives a retransmission request [partial retransmission control reject (REJ) or selective partial retransmission control reject (SREJ)] from the data reception unit 2 via the antenna 10 and the radio reception unit 14. When it comes,
The requested data is read from the transmission buffer 11,
The data is transmitted to the data receiving unit 2 via the wireless transmitting unit 13 and the antenna 10.

In the data receiving section 2, when the received data storage control section 22 receives data from the data transmitting section 1 via the antenna 20 and the radio receiving section 21, the received data storage control section 22 detects a missing frame and an error detection / correction for the data. Is stored in the reception buffer 23. Further, upon detecting the missing frame, the received data storage control unit 22 sends a data loss notification to the retransmission request control unit 25.

The reception level detection section 24 detects the reception level of the signal received by the radio reception section 21 and notifies the retransmission request control section 25 of the reception level. Retransmission request controller 25
If the reception level notified from the reception level detection unit 24 is equal to or larger than a predetermined value, the selective partial retransmission control reject is issued for each missing frame notified from the reception data storage control unit 22.

The retransmission request control unit 25 is provided with the reception level detection unit 2
When the reception level notified from No. 4 becomes equal to or less than the specified value, the retransmission request is stopped. Even if the retransmission request is stopped, normal data communication between the data transmitting unit 1 and the data receiving unit 2 is continued.

The retransmission request control unit 25 is provided with the reception level detection unit 2
4, the retransmission request is resumed, and a partial retransmission control reject (RE) for requesting retransmission of all data after the lost data is resumed.
J) is transmitted to the data transmitting unit 1 via the wireless transmitting unit 26 and the antenna 20. However, if the amount of lost data is small, the retransmission request control unit 25 transmits a selective partial retransmission control reject (SREJ) to the data transmission unit 1 via the wireless transmission unit 26 and the antenna 20.

FIG. 4 is a flowchart showing stop and restart control of the retransmission request in the retransmission request control section 25 of FIG. Referring to FIGS. 3 and 4, retransmission request control section 25
Will be described below.

When a retransmission request is generated by receiving a data loss notification from the received data storage control unit 22 (step S1 in FIG. 4), the retransmission request control unit 25 sets a retransmission request generation flag (step S3 in FIG. 4). ). If a retransmission request has not been issued (step S1 in FIG. 4), retransmission request control section 25 determines whether there is a retransmission request storage (step S2 in FIG. 4), and if not, returns to step S1.

After setting the retransmission request generation flag or if there is a retransmission request storage, the retransmission request control unit 25 determines whether the reception level notified from the reception level detection unit 24 is equal to or higher than a specified value (FIG. 4) At step S4, if the reception level is equal to or higher than the specified value, it is compared with the retransmission request storage to analyze and determine the retransmission content (step S5 in FIG. 4).
A retransmission request is transmitted according to the analysis result and the judgment result (step S6 in FIG. 4).

In this case, the retransmission request control unit 25 transmits a partial retransmission control reject (REJ) according to the retransmission request storage. That is, the retransmission request control unit 25 transmits a partial retransmission control reject if the retransmission request storage exceeds a predetermined fixed value (if there are many lost data), and if the retransmission request storage is less than a certain value (the lost data is (If not) send a selective partial retransmission control reject (SREJ).

On the other hand, if the reception level is not equal to or higher than the specified value, retransmission request control section 25 determines whether or not a retransmission request generation flag is set (step S7 in FIG. 4). If the retransmission request occurrence flag has not been set, the retransmission request control section 25 returns to step S1, and if the retransmission request occurrence flag has been set, clears the retransmission request occurrence flag (step S8 in FIG. 4) and resets the retransmission request. This is stored (step S9 in FIG. 4), and the process returns to step S1.

FIG. 5 is a diagram showing an example of a change in the reception level over time in one embodiment of the present invention, and FIG. 6 shows an example of retransmission when the amount of data loss is small in one embodiment of the present invention. FIG. 7 is a sequence chart showing an example of retransmission when the amount of data loss is large in one embodiment of the present invention. The retransmission operation in one embodiment of the present invention will be described with reference to FIGS.

In one embodiment of the present invention, the reception level is monitored, and only the retransmission request is stopped when the reception level falls below a specified value. That is, even if the retransmission request is stopped, normal data communication is performed as much as possible.

Although a large amount of data has been transmitted from the data transmission unit 1, if data loss has occurred, if the reception level is lower than a specified value (retransmission request stop level) (point B in FIG. 5). -Position between points C and D), the retransmission request is stopped, and the retransmission request is not made.

Thereafter, when the reception level becomes higher than the specified value (in FIG. 5, the position after point D to point E), the retransmission request is resumed, and the retransmission request is performed. In this case, the retransmission request changes depending on the data loss amount.

That is, if the amount of data loss is small,
Only the target data is requested in the selective partial retransmission control reject (SREJ). In FIG.
Data 1 sent from data transmitter 1 to data receiver 2
-If only data 5 out of data 11 is lost, only the target data 5 is requested by the selective partial retransmission control reject (SREJ) (5) after the retransmission request is resumed.

On the other hand, if the data loss amount is large,
In the partial retransmission control reject (REJ), all data after the first lost data will be requested. FIG.
, The data 2 out of the data 1 to the data 11 transmitted from the data transmitting unit 1 to the data receiving unit 2, the data 4
When data 7, data 9, and data 11 are lost, after the retransmission request is resumed, the partial retransmission control reject (R
EJ) The data after the first lost data 2 in (2) is requested. In this case, the retransmission request includes the already received data 3, data 8, and data 10.

As described above, by stopping the retransmission request under the control of the retransmission request control unit 25, it is possible to prevent the occurrence of a large number of retransmission requests for the same signal, and to improve the use efficiency of the communication line.

FIG. 8 is a block diagram showing a configuration of a data communication system according to another embodiment of the present invention. 8, in the data communication system according to another embodiment of the present invention, the reception level detection unit is omitted, the reception data storage control unit 31 of the data reception unit 3 detects the bit error rate, and the retransmission request control unit 32 Except for controlling the retransmission request according to the error rate, the configuration is the same as that of the data communication system according to the embodiment of the present invention shown in FIG. 3, and the same components are denoted by the same reference numerals. The operation of the same component is the same as that of the embodiment of the present invention.

The reception data storage control unit 31
When receiving data from the data transmitting unit 1 via the wireless receiving unit 21, after detecting missing frames and error detection / correction for the data, the receiving buffer 23
To be stored. Further, the received data storage control unit 31 sends the bit error rate obtained from the error detection / correction result to the retransmission request control unit 32, and sends a data loss notification to the retransmission request control unit 32 when a lost frame is detected.

If the bit error rate notified from the received data storage control unit 31 is equal to or less than a preset specified value, the retransmission request control unit 32 selectively selects each missing frame notified from the received data storage control unit 31. Issues a partial retransmission control reject.

When the bit error rate notified from received data storage control section 31 becomes equal to or greater than a predetermined value, retransmission request control section 32 stops the retransmission request. Even if the retransmission request is stopped, normal data communication between the data transmitting unit 1 and the data receiving unit 3 is continued.

When the bit error rate notified from the received data storage control unit 31 falls below a specified value, the retransmission request control unit 32 restarts the retransmission request and requests the retransmission of all data after the lost data. A partial retransmission control reject (REJ) is transmitted to the data transmission unit 1 via the radio transmission unit 26 and the antenna 20. However, the retransmission request control unit 32
When the amount of lost data is small, the selective partial retransmission control reject (SREJ) is transmitted to the radio transmitting unit 26 and the antenna 2
0 to the data transmission unit 1.

FIG. 9 is a flowchart showing stop and restart control of a retransmission request in the retransmission request control section 32 of FIG. Referring to FIGS. 8 and 9, retransmission request control unit 32
Will be described below.

When a retransmission request is generated by receiving a data loss notification from the received data storage control unit 31 (step S11 in FIG. 9), the retransmission request control unit 32 sets a retransmission request generation flag (step S13 in FIG. 9). ). If no retransmission request has been issued (step S11 in FIG. 9), retransmission request control section 25 determines whether or not there is a retransmission request storage (step S12 in FIG. 9).
Return to

After setting the retransmission request generation flag or if there is a retransmission request, retransmission request control section 32 determines whether or not the bit error rate notified from received data storage control section 31 is equal to or less than a specified value ( If the bit error rate is equal to or smaller than the specified value (step S14 in FIG. 9), it is compared with the retransmission request storage to analyze and determine the retransmission content (step S14 in FIG. 9).
15), and transmits a retransmission request according to the analysis result and the determination result (step S16 in FIG. 9).

In this case, the retransmission request control section 32 transmits a partial retransmission control reject (REJ) according to the retransmission request storage. In other words, the retransmission request control unit 32 transmits a partial retransmission control reject if the retransmission request storage exceeds a preset fixed value (if there are many lost data), and if the retransmission request storage is less than a certain value (the lost data is (If not) send a selective partial retransmission control reject (SREJ).

On the other hand, if the bit error rate is not less than the specified value, retransmission request control section 32 determines whether or not a retransmission request occurrence flag is set (step S17 in FIG. 9).
If the retransmission request generation flag is not set, the process returns to step S11. If the retransmission request generation flag is set, the retransmission request control unit 32 clears the retransmission request generation flag (step S18 in FIG. 9), and resets the retransmission request. This is stored (step S19 in FIG. 9), and the process returns to step S11.

As described above, the stop of the retransmission request under the control of the retransmission request control unit 32 can prevent the occurrence of a large number of retransmission requests for the same signal, and can improve the use efficiency of the communication line.

FIG. 10 is a block diagram showing a configuration of a data communication system according to another embodiment of the present invention. Referring to FIG. 10, in a data communication system according to another embodiment of the present invention, a reception data storage control unit 31 of a data reception unit 4 detects a bit error rate, and a retransmission request control unit 41 determines a retransmission request based on a reception level and a bit error rate. The configuration is the same as that of the data communication system according to the embodiment of the present invention shown in FIG. 3 except that the control is performed, and the same components are denoted by the same reference numerals. The operation of the same component is the same as that of the embodiment of the present invention.

The retransmission request control section 41 is provided with the reception level detection section 2
4 and the bit error rate notified by the received data storage control unit 31 is equal to or less than the preset specified value, the notification from the received data storage control unit 31 is performed. A selective partial retransmission control reject is issued for each of the lost frames.

Retransmission request control section 32 receives level detection section 2
When the reception level notified from No. 4 becomes equal to or less than a specified value, or when the bit error rate notified from the received data storage control unit 31 becomes equal to or more than a specified value, the retransmission request is stopped. Even if the retransmission request is stopped, normal data communication between the data transmitting unit 1 and the data receiving unit 4 is continued.

Retransmission request control section 41 receives level detection section 2
When the reception level notified from No. 4 becomes equal to or more than the specified value and the bit error rate notified from the received data storage control unit 31 becomes equal to or less than the specified value, the retransmission request is resumed, and all data after the lost data are retransmitted. A partial retransmission control reject (REJ) for making a request is transmitted to the data transmission unit 1 via the radio transmission unit 26 and the antenna 20. However, if the amount of lost data is small, the retransmission request control unit 41 transmits a selective partial retransmission control reject (SREJ) to the data transmission unit 1 via the wireless transmission unit 26 and the antenna 20.

FIG. 11 is a flowchart showing stop and restart control of the retransmission request in the retransmission request control section 41 of FIG. The stop and restart control of the retransmission request in the retransmission request control unit 41 will be described with reference to FIGS.

When a retransmission request is generated by receiving a data loss notification from the received data storage control unit 31 (step S21 in FIG. 11), the retransmission request control unit 41 sets a retransmission request generation flag (step S23 in FIG. 11). ). If no retransmission request has been issued (step S21 in FIG. 11), retransmission request control section 25 determines whether there is a retransmission request storage (step S22 in FIG. 11), and if not, returns to step S21.

After setting the retransmission request occurrence flag or when there is a retransmission request, retransmission request control section 41 determines whether or not the reception level notified from reception level detection section 24 is equal to or higher than a specified value (FIG. 11). In step S24, if the reception level is equal to or higher than the specified value, it is determined whether the bit error rate notified from the received data storage controller 31 is equal to or lower than the specified value (step S25 in FIG. 11).

If the bit error rate is equal to or less than the specified value, the retransmission request control unit 41 performs a comparison with the retransmission request storage to analyze and determine the retransmission content (step S26 in FIG. 11).
A retransmission request is transmitted according to the analysis result and the judgment result (step S27 in FIG. 11).

In this case, the retransmission request control section 41 transmits a partial retransmission control reject (REJ) according to the retransmission request storage. That is, the retransmission request control unit 41 transmits a partial retransmission control reject if the retransmission request storage exceeds a preset fixed value (if there are many lost data), and if the retransmission request storage is less than a certain value (the lost data is (If not) send a selective partial retransmission control reject (SREJ).

On the other hand, if the reception level is not higher than the specified value or the bit error rate is not lower than the specified value, retransmission request control section 41 determines whether or not a retransmission request occurrence flag is set (step in FIG. 11). S28). If the retransmission request generation flag is not set, the process returns to step S21, and if the retransmission request generation flag is set, the retransmission request generation flag is cleared (FIG. 1).
(1 step S29), the retransmission request is stored (step S30 in FIG. 11), and the process returns to step S21.

As described above, by stopping the retransmission request under the control of the retransmission request control unit 41, it is possible to prevent a large number of retransmission requests for the same signal from being generated, and to improve the efficiency of use of the communication line.

[0069]

As described above, according to the communication line retransmission control device of the present invention, when a loss occurs during data reception and the retransmission control of the lost data is performed, the detected reception level is set in advance. Stop the data retransmission request when the retransmission request level becomes lower than the retransmission request suspension level, and resume the data retransmission request when the reception level becomes higher than the retransmission request suspension level after the retransmission request is suspended, and stop the data retransmission request. By continuing the normal data communication during the communication, the use efficiency of the communication line can be improved.

According to another communication line retransmission control device of the present invention, when a loss occurs during data reception and the retransmission control of the lost data is performed, the detected bit error rate is set to a predetermined specified value. Stops the data retransmission request when it becomes higher, resumes the retransmission request when the bit error rate falls below the specified value after stopping the retransmission request, and continues normal data communication while the data retransmission request is stopped By doing so, there is an effect that the use efficiency of the communication line can be improved.

[Brief description of the drawings]

FIG. 1 is a sequence chart showing a retransmission operation according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a communication amount of a retransmission operation according to the embodiment of the present invention.

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

FIG. 4 is a flowchart showing stop and restart control of a retransmission request in a retransmission request control unit in FIG. 3;

FIG. 5 is a diagram illustrating an example of a change in a reception level over time according to an embodiment of the present invention.

FIG. 6 is a sequence chart showing an example of retransmission when the amount of data loss is small in one embodiment of the present invention.

FIG. 7 is a sequence chart showing an example of retransmission when the amount of data loss is small in one embodiment of the present invention.

FIG. 8 is a block diagram showing a configuration of a data communication system according to another embodiment of the present invention.

9 is a flowchart illustrating stop and restart control of a retransmission request in a retransmission request control unit in FIG. 8;

FIG. 10 is a block diagram showing a configuration of a data communication system according to another embodiment of the present invention.

11 is a flowchart showing stop and restart control of a retransmission request in a retransmission request control unit of FIG. 10;

FIG. 12 is a sequence chart showing a retransmission operation according to a conventional example.

FIG. 13 is a diagram illustrating the traffic of a retransmission operation according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Data transmission part 2, 3, 4 Data reception part 10, 20 Antenna 11 Transmission buffer 12 Transmission control part 13, 26 Radio transmission part 14, 21 Radio reception part 22, 31 Reception data storage control part 23 Reception buffer 24 Reception Level detection unit 25, 32, 41 Retransmission request control unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5K014 AA01 EA08 FA03 FA04 FA05 HA05 5K021 AA08 CC03 DD00 EE01 EE04 5K034 AA06 AA09 BB01 CC01 CC05 DD02 EE03 HH09 MM03 TT02

Claims (22)

[Claims] 1. A communication line retransmission control device for retransmitting lost data when data loss occurs during data reception, comprising: detecting means for detecting a reception level of the data; The data retransmission request is stopped when a reception level becomes lower than a preset retransmission request stop level, and the retransmission request is made when the reception level becomes higher than the retransmission request stop level after the retransmission request is stopped. And a retransmission request control means for resuming the data transmission, wherein normal data communication is continued while the data retransmission request is stopped. 2. The retransmission request control means for requesting retransmission of all data after the first data lost when the data lost during suspension of the data retransmission request is a predetermined amount or more. 2. The apparatus according to claim 1, wherein the partial retransmission control reject is transmitted to the transmitting side.
The communication line retransmission control device according to the above. 3. The retransmission request control means performs a selective partial retransmission control reject for making a retransmission request individually for the lost data when the data lost during the suspension of the data retransmission request is less than the predetermined amount. 3. The communication line retransmission control device according to claim 2, wherein the transmission is performed to the transmission side. 4. The communication line according to claim 2, wherein said retransmission request control means monitors and stores a retransmission request generated during suspension of said data retransmission request. Retransmission control device. 5. The retransmission request control unit according to claim 1, wherein said retransmission request control means determines which of said partial retransmission control rejection and said selective partial retransmission control rejection based on a content of a retransmission request generated during suspension of said data retransmission request. 5. The communication line retransmission control device according to claim 3, wherein it is configured to determine whether or not to transmit. 6. A bit error rate detection means for detecting a bit error rate of the data, wherein the retransmission request control means detects when a reception level detected by the detection means becomes lower than the retransmission request stop level; Stop the data retransmission request at any one of the times when the bit error rate becomes higher than a predetermined value, and after the retransmission request is stopped, the reception level is higher than the retransmission request stop level. The communication line retransmission control device according to any one of claims 1 to 5, wherein the retransmission request is restarted when the bit error rate becomes lower than the prescribed value. 7. A communication line retransmission control device for controlling retransmission of lost data when a loss occurs during data reception, comprising: detecting means for detecting a bit error rate of the data;
When the bit error rate detected by the detection means becomes higher than a predetermined value, the data retransmission request is stopped, and after the retransmission request is stopped, the bit error rate becomes lower than the predetermined value. A communication line retransmission control device, comprising: retransmission request control means for resuming the retransmission request at any time, and continuing normal data communication while the data retransmission request is stopped. 8. The retransmission request control means for requesting retransmission of all data after the first data lost when the data lost during suspension of the data retransmission request is a predetermined amount or more. 8. The apparatus according to claim 7, wherein the partial retransmission control reject is transmitted to the transmitting side.
The communication line retransmission control device according to the above. 9. The retransmission request control means performs a selective partial retransmission control reject for making a retransmission request individually for the lost data when the data lost during the stop of the data retransmission request is less than the predetermined amount. 9. The communication line retransmission control device according to claim 8, wherein the transmission is performed to the transmission side. 10. The communication line according to claim 2, wherein said retransmission request control means monitors and stores a retransmission request generated during suspension of said data retransmission request. Retransmission control device. 11. The retransmission request control means, according to the content of a retransmission request generated during suspension of the data retransmission request, determines which of the partial retransmission control reject and the selective partial retransmission control reject is transmitted to the transmitting side. The communication line retransmission control device according to claim 9 or 10, characterized in that it is configured to determine whether or not to transmit the communication line. 12. A communication line retransmission control method for retransmitting lost data when data loss occurs during data reception, wherein a reception level detected from received data is higher than a preset retransmission request stop level. Stopping the retransmission request when the data has also become low, and having the step of restarting the retransmission request when the reception level becomes higher than the retransmission request stop level after the retransmission request is stopped, A communication line retransmission control method, characterized in that normal data communication is continued while a data retransmission request is stopped. 13. The step of resuming the retransmission request,
When the data lost during the stop of the data retransmission request is a predetermined amount or more, a partial retransmission control reject for sending a retransmission request for all data after the first lost data is sent to the transmission side. The communication line retransmission control method according to claim 12, wherein: 14. The step of resuming the retransmission request,
When the data lost during the suspension of the data retransmission request is less than the predetermined amount, a selective partial retransmission control reject for making a retransmission request individually for the lost data is sent to the transmission side. 14. The communication line retransmission control method according to claim 13, wherein 15. The communication line retransmission control method according to claim 13, further comprising a step of monitoring and storing a retransmission request generated while the data retransmission request is stopped. 16. A method for determining which of the partial retransmission control reject and the selective partial retransmission control reject to send to the transmitting side from the content of a retransmission request generated while the data retransmission request is stopped. 16. The communication line retransmission control method according to claim 14, comprising a step. 17. The step of stopping the retransmission request,
A request for retransmission of the data when the reception level is lower than the retransmission request stop level or when the bit error rate detected from the received data is higher than a predetermined value. Stopping the retransmission request, the retransmission request is stopped when the retransmission request is stopped, the reception level is higher than the retransmission request stop level and the bit error rate is lower than the specified value, the retransmission request 17. The communication line retransmission control method according to claim 12, wherein the communication line retransmission control is restarted. 18. A communication line retransmission control method for retransmitting lost data when data loss occurs during data reception, wherein a bit error rate detected from the received data is higher than a predetermined value. Stopping the retransmission request when the data error occurs, and resuming the retransmission request when the bit error rate becomes lower than the specified value after stopping the retransmission request. A communication line retransmission control method, wherein normal data communication is continued while a request is stopped. 19. The step of restarting the retransmission request,
When the data lost during the stop of the data retransmission request is a predetermined amount or more, a partial retransmission control reject for sending a retransmission request for all data after the first lost data is sent to the transmission side. 19. The communication line retransmission control method according to claim 18, wherein: 20. The step of restarting the retransmission request,
When the data lost during the suspension of the data retransmission request is less than the predetermined amount, a selective partial retransmission control reject for making a retransmission request individually for the lost data is sent to the transmission side. The communication line retransmission control method according to claim 19, wherein 21. The communication line retransmission control method according to claim 19, further comprising a step of monitoring and storing a retransmission request generated while the data retransmission request is stopped. 22. Determine which of the partial retransmission control reject and the selective partial retransmission control reject to send to the transmission side from the content of a retransmission request generated while the data retransmission request is stopped. 22. The communication line retransmission control method according to claim 20, comprising a step.