Method and device for encoding satellite short message based on binary coded decimal (BCD) code

Abstract

The invention relates to a method and a device for encoding a satellite short message based on a binary coded decimal (BCD) code. A new character is encoded and output according to a new code (NC) encoding format by comparing whether the BCD code of a character at the current position is the same as the BCD codes of all previous characters; and repeated characters are encoded and output according to a reference code (RC) encoding format. By the encoding method and the encoding device, the problem of negative compression of the conventional compression method for compressing the BCD code short message can be solved; and a relatively high compression ratio can be obtained under most conditions.

Description

technical field [0001] The invention relates to the field of satellite communication, in particular to a method and device for encoding satellite short messages based on BCD codes. Background technique [0002] Some existing satellites in our country have short message communication capability, and this communication capability has two modes: one is short message communication between satellite communication terminals and terminals, and the other is between satellite communication terminals and short message central stations Communication. [0003] The BCD code effectively utilizes the bandwidth resources of the satellite. As a compact Chinese character code, it is often used in satellite communications. Every 14 bits represent a Chinese character code, which is 2 bits less than the GBK coded Chinese characters currently used by Windows. , It is also more suitable for satellite transmission than the variable-length Chinese character encoding UTF-8 used by Linux by default. ...

AI Technical Summary

Problems solved by technology

However, due to the very limited amount of data in a single short message, it is usually limited to a few hundred Chinese characters to a maximum of one thousand Chinese characters, and the existing compression coding methods are difficult to adapt to such short data and compact coding format , usually negative compression occurs, that is, the compressed short message is larger than the pre-compressed data volume, which restricts the GEO-based short message data communication capability

[0004] Therefore, using traditional compression coding methods to compress and decompress satellite short messages not only fails to save bandwidth, but wastes more bandwidth resources

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