JPH0730590A - Data communication method - Google Patents

Abstract

PURPOSE:To attain efficient communication by sending relevant code data in place of character data when coincident character data are in existence on a table and sending new code data when not in existence. CONSTITUTION:Character data sent from a transmission reception section 1 are compressed and sent to a communication line 3, the data sent from the line 3 are decoded and sent to other transmission reception section 1. When characters in total 24 bytes being 3X8 bytes are sent, a comparison retrieval section 22 makes comparison and retrieval, the data are segmented into three by each of 8-bits and whether or not the data are already registered is retrieved from a code table 25. The character data not registered are registered in the table 25 together with new code data and the character data are sent to a receiver side coded unit 2 via the line. 3. An identifier is provided to the code data to identify that the data are data in a code table. Thus, number of bytes is saved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data communication method for compressing data for communication.

[0002]

2. Description of the Related Art Communication capacity and communication speed are important items for data communication. In recent years, satellite communication has been actively used, and devising the line usage fee and communication speed has become an important issue. In particular, mobile communication using satellites is also frequently used. In this case, when transmitting from the mobile side, the communication speed (baud rate) may be extremely limited. In many cases, how to reduce (compress) the amount of communication data is a future issue. On the other hand, many of the conventional techniques are intended for the present terrestrial line, and there are few that are particularly suitable for the mobile communication. For example, there is a method (example: RADIX50) of reducing the communication data amount by using a dedicated code instead of a code such as JIS or ASCII. Further, there is a method in which a code corresponding to a communication code and a communication content is created in advance, communication itself is performed only by the code, and communication is performed while conversion / restoration is performed on the transmission side / reception side. For example, as shown in FIG. 4, the information transmitted from the transmission / reception unit A11 is converted into a code by the fixed table in the fixed encoding unit A203,
It is sent to the communication line. Next, the code sent from the communication line 3 is restored to the original information by the fixed table of the fixed coding unit B204, and sent to the transmitting / receiving unit B12.

[0003]

[Problems to be Solved by the Invention] The conventional method has the following problems. <B> When the dedicated code is used, both the transmitting and receiving sides need to be able to identify the dedicated code, which poses a problem that the systems that communicate with each other are limited. <B> In a system in which both the transmitting and receiving sides have a fixed code table, there is a problem that information not in this code table cannot be transmitted. <C> In a system having a fixed code table, if a third party obtains this code table, the information can be acquired, and the information is easily leaked to the third party.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a data communication method for compressing data for efficient communication.

[0005]

SUMMARY OF THE INVENTION The present invention is a data communication method for sending data from a transmitter to a receiver via a transmitter coding unit, a communication line, and a receiver coding unit. The character data input to the credit encoding unit is divided into predetermined bytes, and the separated character data is compared with the character data stored in the table inside the transmission encoding unit, and matches on the table. If there is no character data to be stored, the delimited character data is stored as new character data on the table by adding new code data, and the delimited character data is sent to the communication line. If there is a matching character data in the table, the corresponding code data is sent to the communication line instead of the character data, and the receiving coded unit is sent from the communication line. When the printer receives the data, the received character data is stored as a new character data on the table inside the receiving encoding unit with the new code data added, and the character data is output to the receiving unit and received. The coded data is replaced with the corresponding character data on the table inside the receiving coding unit and is output to the receiving section, or the table inside the sending coding unit and the receiving data is used. A data communication method characterized by giving usage frequency information to a table inside the encoding unit, or between character data stored in a table inside the transmitting encoding unit and a table inside the receiving encoding unit. A data communication method characterized by having information on connection relation to
In the data communication method, the connection relation information includes presence / absence of a connection relation between character data, connected character data, and code data corresponding to the connected character data.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. <B> Outline of Example: Communication method for data communication of character (alphanumeric, kanji, etc.) information over telephone line, leased line, satellite line, etc., related to communication capacity, communication speed, communication charge, etc. It improves the problem of and enables more efficient communication. This communication method is a method of automatically coding communication contents while comparing / learning communication information patterns on the transmitting side and the receiving side to compress the communication data amount. Therefore, by installing a unit for comparative learning on both sides of communication, any system can be supported. That is, in FIG. 1 to FIG. 3, both the transmitting side and the receiving side encoding units 2, 201, 202 monitor and learn the character blocks to be transmitted and received, and automatically encode and group them by a predetermined method. Is in the way to restore and restore them.

<B> Coding Unit The coding unit 2 is inserted between the transmitting / receiving unit 1 and the communication line 3. Interface 2 inside the code unit
Reference numerals 1 and 23 are for exchanging information with an external system or a communication line, and use RS-232C or the like. The comparison / retrieval unit 22 executes a comparison retrieval process.
When the processing procedure is configured by a microprocessor or the like, the processing procedure is programmed in advance. The character data sent from the transmission / reception unit 1 is compressed and sent to the communication line 3, and the data sent from the communication line 3 is decompressed and sent to another transmission / reception unit 1. When transmitting and receiving the character data of 8 bytes x 3 pieces of "Patent Construction Co., Ltd. technical development" for a total of 24 bytes from the transmission / reception unit A to the transmission / reception unit B, the comparison / retrieval unit 22 performs comparison via the interface 21. , The search is done. First, the character data to be sent is divided into a predetermined number of bytes, for example, every 8 bytes. That is, "patent construction", "corporation", "technology development"
It is divided into three and is searched for whether it is already registered in the code table 25. Although “patent construction” has already been registered in the code table 25, “corporation” and “technical development” are not registered. In that case, the already registered character data is converted into the code data described in the code table. That is, "patent construction" is [0
1]. The unregistered character data “corporation” and “technical development” are newly registered in this table together with the code data [02] and [03], and the character data itself is encoded by the receiving side via the communication line 3. Sent to unit B. That is, "corporation", "technology development"
Will be sent as character data. The code table identifier [FF] is added to these code data in order to identify that they are data in the code table. Therefore, the receiver coding unit B202
The data sent to is “FF01”, “Co., Ltd.” and “Technology development”. 2 bytes of [FF01] and 16 bytes of “Corporation” and “Technology development” total, 18 bytes of data. Will be transferred. On the other hand, when "Technology Development Co., Ltd." is directly transferred as character data, this data has a total of 24 bytes in 8 bytes x 3. Therefore, 24 bytes-18 bytes,
That is, the transfer amount of 6 bytes is saved.

On the receiving side, the coding unit B202
Then, the comparison / search unit 22 compares and searches the received data. Since the code table of the encoding unit B202 also has the same table as the encoding unit A, the received code data can be restored to the original character data. That is, for the data of [FF01], [F
The code table is identified from F], “patent construction” is determined from [01], and the character data is restored. Also,
Since "Technology Development Co., Ltd." was sent as is,
It is not necessary to convert, and finally, the entire character data of "Patent Construction Co., Ltd. Technical Development" is sent to the transmitting / receiving unit B12. Here, "corporation" and "technical development" are newly registered in the code table of the encoding unit B202 together with the code data [02] and [03]. Since this registration rule is the same as that registered on the transmitting side, learning is performed so that the contents of the code tables on the transmitting side and the receiving side are always the same. As a result, as shown in FIG.
The code data for each of "Co., Ltd." and "Technology Development" is
Same for both sender and receiver tables, [02],
It becomes [03].

<C> Code table and group table The code table 25 contains code data, character data,
It has columns of presence / absence of connection and frequency. For example,
In FIG. 2, when the code data is [01], the character data is “patent construction”, the connection column indicates whether or not there is a relation with other character data, and the frequency column is transferred four times. Is shown. Details of the connection relationship are shown in the group table 26, and this group table 26 has a column of code data and a column of backward connection relationship of character data. For example, 1 and 2 are described as the code data of [01] in the group table 26. That is, the connection relation between [01] and [02] in the code table, that is, the character string of “Patent Construction Co., Ltd.” is registered. Similarly, 2 and 3 are described in the code data of [02],
It indicates that the character string “Technical Development Co., Ltd.” is registered. In this way, if coded in groups, a large number of characters can be transferred at once by simply transferring the group code. An identifier [FE] of the code table is given to identify the code data of the group table. For example, once you transfer "Technical Development of Patent Construction Co., Ltd.", the data of Fig. 2 is created in the code table and group table of the sending side and the receiving side. Group table identifier and code,
And the code table identifier and code, that is, [FE0
1] and [FF03] need only be sent. As a result, the character data requires a transfer amount of 24 bytes, but the code data has 4 bytes of [FE01] and [FF03], and the transfer amount of 20 bytes can be saved. In the frequency column,
It is used for organizing the table memory 24 when searching from the most frequent ones to improve the search efficiency, or when the memory capacity of the coding unit is limited.
As a result of the above functions working, information is accumulated in the table as the communication progresses, and the code table specific to the system,
Group table is created automatically. Here, the table code identifier [FF] and the group code identifier [FE] are 1 byte, but these may be arbitrarily determined in accordance with the communication information.

[0010]

The present invention has the following effects. <B> Since the character information to be communicated can be shortened, the transmission time can be shortened, the communication fee can be reduced, and the line with a slow communication speed can be effectively used. <B> Code table and group table can be created automatically. <C> If it is a system that communicates character information, this device can be used immediately by connecting it to a communication line. <D> Since the coded information can be decrypted only at two locations, the transmitting side and the receiving side, it also functions as confidential protection of data.

[Brief description of drawings]

FIG. 1 is a block diagram of a coding unit of the present invention.

FIG. 2 is a block diagram of the table of the present invention.

FIG. 3 is a connection diagram between transmission / reception systems of the present invention.

FIG. 4 is a connection diagram between conventional transmission / reception systems.

Claims (4)

[Claims] 1. A data communication method for transmitting data from a transmitter to a receiver through a transmitter coding unit, a communication line, and a receiver coding unit, wherein a character input from the transmitter to the transmitter coding unit. The data is divided into predetermined bytes, and the delimited character data is compared with the character data stored in the table inside the transmission encoding unit. If there is no matching character data in the table, The coded character data is stored as new character data on the table by adding new code data, the coded character data is sent to the communication line, and there is matching character data on the table. In this case, if the corresponding code data is sent to the communication line instead of the character data and the receiving coding unit receives the data from the communication line. The received character data is stored as a new character data on the table inside the receiving encoding unit with the new code data added, and the character data is output to the receiving unit, and the received code data is the receiving code. A data communication method characterized in that it is replaced with corresponding character data on a table inside the digitizing unit and is output to the receiving unit. 2. The data communication method according to claim 1, wherein use frequency information is added to a table inside the transmission coding unit and a table inside the reception coding unit. , Data communication method. 3. The data communication method according to claim 1, wherein the character data stored in the table inside the transmission coding unit and the character data stored in the table inside the reception coding unit are connected to each other. A data communication method characterized by having information of. 4. The data communication method according to claim 3, wherein the connection relationship information includes the presence or absence of a connection relationship between character data, character data to be connected, and the character to be connected. A data communication method, which is code data corresponding to data.