Research On Physical Layer Coding And Security

Due to the openness and broadcast nature of wireless mediums,on the one hand,packets are easy to be lost during wireless communication;on the other hand,wireless communication is vulnerable to potential security threats.In order to improve the quality of wireless transmission,channel coding can be used.In recent years,a new research hotspot is fountain code.In order to improve security,a lot of the physical layer security technology has been proposed in the literature,such as using artificial noise,beamforming and so on.Combining these two points together,this paper studies the physical layer security technologies based on fountain codes.In this paper,the main work is as follows:1.Study the optimization of fountain codes.In the point-to-point transmission system,this paper proposes a design of LT code with feedback,which can reduce the decoding overhead,and improve the decoding performance.In multipoint transmission system,this paper proposes a collaborative LT code design,which can improve the average decoding performance.2.Study a secure storage technology based on the fountain codes.Based on the characteristics of fountain codes,this paper proposes anew coding storage technology.After encoding with fountain codes,data are stored in multiple independent storage.On the one hand,anti-destroying ability can be improved due to more storage;on the other hand,due to solvability conditions of fountain codes,resistance of eavesdropping can be improved.3.Study a secret key negotiation scheme based on the physical layer coding.Using the packet loss difference of wireless channels,a secret key negotiation scheme is proposed,which can negotiate a secret key between Alice and Bob with high success rate,and at the same time make the secret key eavesdropped by Eve with low enough probability.4.Study the secure transmission technology based on the physical layer coding.Using the random linear feature of fountain codes and packet loss difference of wireless physical channels,this paper proposes a secure transmission technology,which can guarantee to realize reliable transmission between Alice and Bob,and at the same time make cracking rate of eavesdropping very low.