JPS5810899B2 - Unidirectional broadcast communication method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a unidirectional broadcast communication system, and particularly to a communication system for transmitting the same information to multiple receiving stations and returning a response signal from the receiving station to the transmitting station. .

General broadcast communication methods include one in which information is unilaterally communicated from a transmitting station to a receiving station and no response signal is sent back, such as broadcast communication, and one in which information is transmitted from a transmitting station to a receiving station. In some cases, after unidirectional communication, a response signal is sent back from the receiving station to the transmitting station.

Regarding the latter method, conventionally, as shown in FIG. By transmitting the signal, the upper receiving station 5 transmits the received message etc. to the terminal 6 of the lower receiving station 8.
, and sent out via the transmission path 7.

When the lower receiving station 8 cannot operate normally or when an error occurs in the received message, the lower receiving station 8 returns a negative signal to the upper receiving station 5 via the terminal 9 and the transmission line 10, and the upper receiving station Station 5 also has terminal 11 and transmission line 12.
This is returned to the transmitting station 1 via.

The transmitting station 1 that has received this transmits the same information again to the receiving station 5 side.

Conventionally, the upper receiving station 5 unconditionally returns the response signal sent by the lower receiving station 8 to the transmitting station 1, so the rate at which information reaches the specified receiving station 8 (hereinafter referred to as the arrival rate) is However, as shown in FIG. 2, the disadvantage is that it takes a long time to transmit all the information (hereinafter referred to as transmission time).

That is, in FIG. 2, when the upper receiving station (MRV) 5 first sends the information 14 received from the transmitting station 1 to the lower receiving station 8, negative responses are received from the two stations, and this is sent to the transmitting station 1. After sending the information back to
)8.

In this case as well, if there is a negative response from one more station,
The receiving station 5 sends this back to the transmitting station 1, and the same information 14 is sent again.
Send out.

After all, in FIG. 2, information 14 is sent out three times, and then information 15 is sent out, until there is no negative response.

In this way, until information 14 to information 15 is sent out,
Because it takes time, the method of FIG. 1 requires a long transmission time.

An object of the present invention is to reduce the number of retransmissions from the transmitting station without retransmitting the same information until there are no negative responses in a broadcast communication system in which a response signal is sent back from the receiving station to the transmitting station. An object of the present invention is to provide a unidirectional broadcast communication system that can shorten transmission time.

The unidirectional broadcast communication system of the present invention is a unidirectional broadcast communication system in which a response signal is returned from a lower station to an upper station, and from the upper station to a transmitting station, in which the upper station has a response ratio comparison means and a retransmission frequency checking means. Then, the response ratio comparing means compares the ratio of multiple lower stations that have issued retransmission requests with the set value, and when the ratio is less than the set value, it is assumed that all the lower stations have affirmed, and the ratio is set to the set value. When the number of retransmissions exceeds a set value, the same broadcast message is retransmitted to the lower station, and when the number of retransmissions exceeds a set value, a negative response signal is sent to the transmitting station.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is an internal block diagram of the upper receiving station of the present invention.

The upper receiving station 5 of the present invention includes a received signal analyzing section 501 that analyzes the signal received from the transmitting station 1, a signal distribution section 502 that distributes the signal to the lower receiving station 8, and a counting response signal from the lower receiving station 6. Negative response rate comparison unit 503 that detects the rate by
, a retransmission count check unit 504 that monitors the number of retransmissions;
and a response signal sending unit 5 that sends a response signal to the transmitting station 1
It is equipped with 05.

First, a signal input from the transmitting station 1 to the terminal 4 is analyzed by the received signal analysis section 501, and if it is a received message for the lower receiving station 8, it is inputted to the signal distribution section 502 via the line 51, and the signal is Terminal 6 from distribution section 502
, and is sent to the lower receiving station 8 via the transmission line 7.

At the same time, values for the number of negative responses and the number of retransmissions are set from the analysis unit 501 via line 50 to the negative response ratio comparison unit 503 and the number of retransmissions checking unit 504, respectively.

Note that this value can also be specified from the transmitting station 1.

When the lower receiving station 8 cannot operate normally or when an error is detected in the received signal, the lower receiving station 8 sends a negative response signal to the upper receiving station 5 via the terminal 9 and the transmission line 10.

In the upper receiving station 5, the negative response ratio comparison unit 503 compares the ratio of the number of negative response signals returned within a certain period of time with a set value, and if the ratio is less than the set value, all lower receiving stations 8 have affirmed. It is considered as such and the operation is terminated.

For example, if the number of lower receiving stations 8 targeted for the first transmission is 5 and the setting value is 315, and the number of negative response signals actually returned is 2, the ratio will be 215. Since it is smaller than the set value 315, no retransmission is performed.

Furthermore, when the number of actually returned negative response signals is 4, the ratio is 415, which is larger than the set value.
Start 04.

The number of retransmissions check section 504 compares the number of retransmissions with a set value, and if it is less than the set value, activates the signal distribution section 502 via the line 53 to retransmit the same signal.

Note that the signal distribution unit 502 stores the message in the memory every time.

For example, when the set value is 2, the signal distribution unit 502 is activated and retransmission is performed until the second time.

If the set value is exceeded, the retransmission count checking section 504 activates the response signal sending section 505 via the line 54,
A negative response signal is sent to the transmitting station 1 from the terminal 11.

When the transmitting station 1 receives the negative response signal from the upper receiving station 5, it compares the ratio with the set value along with the negative response signals from other upper receiving stations 5, and when it is less than the set value, it terminates the operation, and If the set value is exceeded, retransmission is performed.

That is, the relationship between the transmitting station 1 and the plurality of upper receiving stations 5 is the same as the relationship between the upper receiving station 5 and the plurality of lower receiving stations 8.

Note that in the transmitting station 1 and the upper receiving station 5, fixed values within the own station may be used for the number of retransmissions and the negative response rate.

FIG. 4 is an internal block diagram of the transmitting station of the present invention.

The transmitting station 1 has almost the same configuration as the upper receiving station 5 shown in FIG.
1 and the response signal sending unit 505 is replaced with the transmission control unit 100, and the other circuits, wiring, etc. are completely the same, so that it is suitable for mass production.

To send out the first signal, the sending signal generating section 101 is activated by the sending control section 100, and the generated signal is sent to the line 5.
1 to the signal distribution unit 502, and the signal distribution unit 5
02 to multiple upper receiving stations 5 via terminal 2 and transmission line 3.
will be sent to.

At the same time, values for the number of negative responses and the number of retransmissions are set from the signal generation unit 101 to the negative response ratio comparison unit 503 and the number of retransmissions checking unit 504 via the line 50.

As described above, in the upper receiving station 5, when a retransmission request exceeds the set value of the retransmission count checking section 504, a negative response signal is sent from the response signal sending section 505 to the terminal 11 and the transmission line 1.
It is sent via 2.

The negative response ratio comparison unit 503 of the transmitting station 1 compares the ratio of the number of negative response signals returned within a certain period of time with a set value,
If it is less than or equal to the set value, it is assumed that all the upper receiving stations 5 have affirmed, and the operation ends.

Further, if the ratio of the number of returned negative response signals exceeds a set value, a retransmission count check unit 504 is activated via line 52 in order to request retransmission.

The number of retransmissions check section 504 compares the number of retransmissions with a set value, and if the number of retransmissions is less than the set value, sends the same signal from the signal distribution section 502 to the transmission line 3 via the line 53.

If the number of retransmissions exceeds the set value, a negative response signal is sent from the retransmission number checking section 504 to the control section 100 via the line 54.

Thereby, the transmission control unit 100 determines whether to end or continue the process.

In FIGS. 3 and 4, only a negative response signal is sent to the upper stations 1 and 5 through the transmission line 10.degree. 12, but an affirmative response signal can also be returned.

In this case, the negative response circuit section 503 determines the percentage of positive responses, and if the percentage exceeds the set value, the response signal is transmitted to the response signal sending section 505 or the transmission control section 100 via the signal path 56.
make it work.

Also, when the percentage of positive responses is less than the set value, the signal distribution unit 50
The signal is retransmitted from 2.

5 and 6 are line configuration diagrams of a unidirectional broadcast communication system showing other embodiments of the present invention, respectively.

Although FIGS. 1 to 4 show branch line transmission lines 3 and 7, loop line transmission lines 3 and 7 as shown in FIG. 5, or satellite repeater 16 as shown in FIG. The present invention can also be applied to the transmission lines 3 and 7 via.

That is, in FIG. 5, the upper receiving station 5 is connected via the loop line transmission line 3, and the lower level receiving station 8 is connected via the loop line transmission line 7.

In FIG. 6, an upper receiving station 5 is connected to transmission lines 3 and 12 via a satellite repeater 16, and a lower receiving station 8 is connected to a transmission line 7°10 via another satellite repeater 16. is connected.

As explained above, according to the present invention, in unidirectional broadcast communication that returns a response signal, the transmitting station or relay station unconditionally processes the response signal from the lower station, and repeats the response as many times as necessary until there are no negative responses. Since the same broadcast message is not retransmitted, the number of retransmissions from the transmitting station is reduced, and the transmission time can be shortened.

Further, since the set value for checking the rate of negative responses can be controlled from the higher level station, the rate of arrival at the mesh body can be made variable.

[Brief explanation of the drawing]

Figure 1 is a line configuration diagram of the conventional unidirectional broadcast communication system.
The figure is a time chart showing the control procedure between the upper receiving station and the lower receiving station in Fig. 1, Fig. 3 is a block diagram inside the upper receiving station showing an embodiment of the present invention, and Fig. 4 is a diagram showing the embodiment of the present invention. The block diagram inside the transmitting station shown in FIG. 5, and FIG. 6 are line configuration diagrams of a unidirectional broadcast communication system showing other embodiments of the present invention, and show a case where a loop line or an artificial satellite is used. It is something. 1: Transmitting station, 3, 7, 10, 12: Transmission line, 5: Upper receiving station, 8: Lower receiving station, 16: Satellite repeater, 100
: transmission control section, 101: transmission signal generation section, 501: received signal analysis section, 502: signal distribution section, 503: negative response ratio comparison section, 504: retransmission number checking section, 505: response signal transmission section.

Claims (1)

[Scope of Claims] 1. In a unidirectional broadcast communication system in which a response signal is returned from a lower station to an upper station, and from the upper station to a transmitting station, the upper station has a response ratio comparing means and a retransmission frequency checking means, The ratio of multiple lower stations that have issued retransmission requests is compared with a set value using the ratio comparison means, and when the ratio is less than the set value, it is assumed that all the lower stations have affirmed, and when the ratio exceeds the set value, it is assumed that the lower stations have all accepted the request. A unidirectional broadcast communication system characterized in that the same broadcast message is retransmitted to a lower station, and furthermore, when the number of retransmissions exceeds a set value by means for checking the number of retransmissions, a negative response signal is sent to the transmitting station. 2. The unidirectional broadcast communication system according to claim 1, characterized in that when the upper station is a transmitting station, the same comparison is made and a negative response signal is sent to transmission control means in the transmitting station. .