Information transmission method combining artificial scrambling and ldpc secure coding in satellite-earth link

Abstract

The invention relates to an information transmission method with combination of artificial scrambling and LDPC secure coding in a satellite-ground link, and belongs to the technical field of satellite communication. The method includes: step 1, calculating a state vector of a main channel; step 2, calculating a state information matrix of the main channel; step 3, performing LDPC coding on to-be-sent information; step 4, constructing artificial noise z orthogonal to the main channel; step 5, calculating a sending weight of the to-be-sent information, wherein the sending weight enables a private interruption probability to be minimum; step 6, continuously sending the coded to-be-sent information, and sending the artificial noise by employing a multi-antenna emission mode; and step 7, performing decoding by employing a BP decoding algorithm by a receiving end. According to the method, in an information transmission process, channel state information is introduced to LDPC coding so that the security and the reliability of communication are guaranteed; the coding method based on the channel state information is employed so that problems during the application of the conventional encryption algorithm in the satellite communication process is avoided; and the complexity of satellite secret communication is reduced.

Description

technical field [0001] The invention belongs to the technical field of satellite communication, and in particular relates to an information transmission method combining artificial scrambling and LDPC security coding in a satellite-ground link. Background technique [0002] Compared with terrestrial wireless communications, satellite communications with open orbits and large-scale broadcast characteristics are more vulnerable to security threats such as eavesdropping and interception. The existing countermeasures are mainly to encrypt the data and ensure security at the upper layer of the communication protocol stack. The main problems of the encryption processing are as follows: (1) The probability of cracking is high. Due to the limited processing capacity of satellites, it is difficult to handle complex encryption algorithms. With the rapid development of computers and the emergence of new concepts such as cloud computing and supercomputing, traditional encryption algorit...

AI Technical Summary

Problems solved by technology

Compared with terrestrial communication, satellite communication channels have a more complex communication environment. There are many problems in the application of existing terrestrial communication physical layer security strategies in satellite communication, including not fully considering the reciprocity and uniqueness of communication physical channels. and other characteristics, the long delay of the link, the complex composition of the satellite communication channel, etc., so it cannot be applied to the satellite security communication

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