JPS5837738B2 - Message accuracy check method - Google Patents

Description

[Detailed Description of the Invention] The present invention is mainly applicable to cases where a transmitting station transmits a digital code message in broadcast mode to multiple receiving stations distributed over a wide area using a wireless line with poor transmission quality. The present invention relates to an inspection method in which the transmission side determines the rate at which telegrams for each receiving station are received without error (this is referred to as the probability rate), or the rate of typographical errors conversely.

Conventionally, in order for a transmitting station to determine the probability of message delivery to a receiving station,
After the transmission of one message is completed, a person on the receiving side judges the contents of the received message and replies to the sending side using, for example, Morse code.

Therefore, the disadvantage is that it takes a very long time to obtain responses from all the receiving stations.

There is also a method in which the sender receives a reply each time a character is sent, but such methods have a slow effective transmission speed and are not suitable for broadcast mode communication that targets a large number of mobile objects moving over a wide area. do not have.

The present invention was developed to eliminate the drawbacks of the conventional method, and has the advantage that the message probability on the receiving station side can be determined quickly and accurately.

The present invention will be explained in detail below using examples.

Figure 1 shows an example of the configuration of a parent-child communication system, where A is the master station (telegram inspection station), and b1, b2, b3, ... bn are 1,000 stations (telegram inspection stations) distributed over a wide area. It is.

Figures 2 and 3 are circuit configuration examples of transmitting and receiving equipment for the master station and slave station, respectively. Figure 4 is an explanatory diagram of the message inspection process. Figure 5 shows the confirmation of the data received by the master station from the slave station. It is a diagram showing an example of a response rate or a typographical error rate.

The master station A in FIG. 1 uses the transmitting/receiving device in FIG. 2 to automatically receive patterns indicating the message probability from each slave station b1, b2, . Based on this, the message probability for each slave station is determined.

First, in order for the master station to transmit a message in broadcast mode, the transmitter 4 is operated by the control unit 6 in FIG. 2, and then the terminal equipment (
For example, a digital code from a keyboard of a printing telegraph machine or a tape reader) is input into the interface section 1.

This digital information character is, for example, as shown in Figure 4 1.
1, ■2, ■3, ■4..., then one character (
word) 101011 in 6-bit configuration. 001010
,... and so on.

To these codes, an error correction code (referred to as a parity code, for which a known BCH code or the like is used) is added to each word in the next error correction adding section 2.

FIG. 4 is an example of this, in which an 8-bit parity code P is inserted and added next to 6 bits of one word.

In other words, parity code P1 for 101011 in ■1
is 01010011, I2 is 001010, and P2 is 11100101.

The signal to which this parity code has been added is further distributed according to a certain rule using a well-known time interleaving method as a measure to prevent burst errors (continuous errors) due to interference and noise in the transmission line, and At the beginning of this message, there is a synchronization code S1 to notify the receiving side of the start of error correction, and after the end of message transmission, a synchronization code S1 is used to indicate the end of one message and to request a reply of the message probability from the slave station side.
Add 2 to each.

The well-known M-series codes are used as codes for these S1 and S2, and these are supplied from the synchronization signal generator 5 in FIG.

FIG. 4 shows an interleaved transmission format including a synchronization code.

Such a digital code is converted into a modulated signal to be transmitted over a wireless line by the modulator 3 in FIG. 2, and then transmitted via the transmitter and antenna 4.

On the slave station side, a transmitting/receiving device as shown in FIG. 3 receives the message from the master station, and transmits a response pattern indicating the probability.

After the reply pattern is transmitted, it is automatically controlled to enter the reception mode by a control signal from the control section 6 shown in FIG.

That is, T in FIG. 4, 3 and 4. After that, it will be in reception mode.

Next, the operation of the slave station will be explained in more detail.

The transmitted message is received by the receiver 12 including the antenna shown in FIG. Determine whether or not there is.

The synchronization signal detection unit 18 determines the start of error correction and the start of deinterleaving (restoring codes time-interleaved on the transmitting side to the original code arrangement).

In other words, on the slave station side, a synchronization code pattern specified between the master station and the slave station is set in advance in the synchronization signal detection unit 18 of the slave station, and if a certain number or more bits of the received code match, an error is detected. It is determined that this is the correction start position.

For example, when a received signal as shown in FIG.
Consists of 1 bit.

At this time, if n-5 consists of 2n-1 = 31), if more than half (16 bits) of them match the pattern, it is determined to be a synchronizing signal, and the received ■'1 (original ■1), I)'1 (original P1), I
Error correction detection is performed using '2, P'2...

Then, the number of characters determined to be erroneous is counted by the counter section 15, and only the characters determined to be free from errors are outputted to the output section 15.
7, each character is output to the terminal device.

Furthermore, the synchronization signal detection unit 18 determines the synchronization code S2 for the end of the message using the same determination method as S1. When the synchronization signal is detected and determined, the timer circuit 19 is activated by the output from the synchronization signal detection unit 18. The reference clock operates an internal counter to set the order in which the own station sends a response.

At this time, a time difference determined by the count is set in advance so that the response order of each slave station does not overlap.

The response pattern for message delivery rate is as follows.

The number of characters in one message from the synchronization signal S1 to S82 is counted by the counting unit 15, which makes up m characters in total, and on the other hand, the number of erroneous characters detected by the error correction detection unit 14 and counted by the counter unit 15 as described above is If there are n characters, the error rate is P.

1 (n/m) x 100%.

This typographical error rate is divided into a plurality of categories between 0 and 100%, and response patterns for each category are determined in advance between the master station and the slave station.

For example, 0-5% is S3, 5-10% is S4, 10-3
A pattern such as 0% is S5 and 30% or more is S6.

Now, in FIG. 4, the slave station bt (FIG. 1) is at the transmission end time T of the master station.

After that, first operate the transmitter for t1 seconds and check the error rate (0 to 5)
Suppose you want to send an S3 pattern for %.

More specifically, a control signal from the timer section 19 in FIG. 3 is sent to the transmitter/receiver control section 20 to switch the mode from reception to transmission and operate the transmitter 23.

Returning to the previous explanation, the number of characters and the number of error characters in one received message are temporarily stored from the counter section 15 to the memory section 16, and are converted into an error rate pattern, for example S3, by the (code) conversion section 21, and then converted to the modulation section 22. When the signal is inputted to , it is converted into a modulated signal for transmission at radio frequency, and is transmitted as a response pattern from the antenna when the transmitter 24 operates.

Once the reply pattern has been transmitted, the transmitter is automatically turned off (t1 seconds after To) by a control signal from the transmission/reception control section 20.

Subsequently, the slave station with the next response order, for example, the b2 station (FIG. 1), transmits the response pattern S4 using the same transmission method as the b1 station.

8 and 9 in FIG. 4 show this, and at time t2 after t1, the transmitter of station b2 operates and a response pattern S4 as shown in 9 is generated.
Send.

Thereafter, response patterns from each slave station b3, b4, . . . bn are transmitted in the same manner.

The master station uses the receiving device shown in FIG. 2 to sequentially receive response patterns from a plurality of slave stations, and determines the message probability of each slave station.

To explain in detail, the signal received by the receiving antenna and receiver 7 is converted into a digital signal by the demodulator 8, and the next stage synchronization signal detector 9 receives the signal using the same method as that used by the slave station to determine the 81, S2 pattern. do.

In this case, to determine from which slave station the currently received pattern has arrived, the transmission/reception control section switches from transmission to reception, and then sets the timer section 10 to time T.

(FIG. 4), it is determined which slave station is receiving according to the elapse of a preset time, and based on this, the output section 11 is controlled to output the received code to the terminal equipment.

As an example of output to a terminal device, for example, the determination result is printed for each slave station to a printer of a printing telegraph machine as shown in FIG.

Tazo Shiko's printing example shows that among the response patterns, S3 is A (excellent), S4 is B (good), S5 is C (medium), and S6 is D (
The master station can determine which slave station the message should be retransmitted to, and either selectively calls only this slave station and retransmits, or selects another frequency and retransmits.

As explained in detail above, according to the method of the present invention, when a master station transmits a message to a slave station in broadcast mode, the probability of delivery to each slave station can be efficiently determined, thereby improving the operational effectiveness of the communication line. This results in significant practical effects.

[Brief explanation of drawings]

Figure 1 is an example of the configuration of a parent-child communication system, Figures 2 and 3 are examples of the circuit configuration of the transmitting and receiving equipment of the master station and slave station, respectively, Figure 4 is a time chart for message inspection, and Figure 5 The figure is an example of a reply received by the master station from the slave station. 1... Input interface section, 2...
・Error correction addition section, 3, 22...Modulation section, 4,
23... Antenna and transmitter, 5... Synchronization signal generation section, 6, 20... Transmission and reception control section,
7, 12... Antenna and receiver, 8, 13...
... Demodulation section, 9, 18 ... Synchronization signal detection section, 10, 19 ... Timer part, 11, 17 ...
... Output interface section, 14 ... Error correction detection section, 15 ... Counter section, 16 ...
...Memory, 21... Conversion section.

Claims (1)

[Claims] 1 When transmitting a message in broadcast format from a master station to multiple slave stations, the master station adds a parity code to each word (character) of information and also adds a synchronization code to indicate the end of transmission of one message. Each slave station performs error detection using the parity code added to each word of the received message, records the number of error words, and when the synchronization code for the end of transmission of one message arrives, The transmission device installed in the slave station is turned on in order according to the response transmission order and time interval determined between the master station and each slave station, and the error rate or its A message probability checking method characterized in that by transmitting codes indicating reciprocal numbers, a master station that receives these codes determines the message probability for each slave station.