Design Of Laser Ranging Data Transmission System Based On Hybrid Encryption

Laser ranging is widely used in military surveying and geographic mapping due to its high accuracy,high resolution,and good anti-interference characteristics.With the improvement of measurement requirements in the above fields,the amount of data generated by laser ranging is huger,and the accuracy requirements are also higher,resulting in higher requirements for transmission efficiency and accuracy.At the same time,in order to protect the information carried by ranging data in the above fields,improving data security is also an aspect that cannot be ignored.Therefore,this thesis uses the FPGA device integrated with ARM architecture to design and implement a data transmission system based on TCP/IP protocol that can encode and encrypt data with variable length by using a software hardware collaborative design approach.Firstly,this thesis introduces the relevant theories of data transmission system,software and hardware design schemes.Based on this,according to the characteristics of laser ranging output data,using FPGA hardware logic design and implement a twostage pipeline structure Varint encoding algorithm and decoding module.At the same time,a storage optimization scheme for variable byte length is proposed.In order to protect the security of data and key,a hybrid encryption and decryption method is adopted,and the AES circuit is optimized as a semi-internal and external pipeline structure to improve the data throughput.For the keys that only need to be encrypted once,RSA algorithm is implemented using ME-LR modular exponentiation and shiftadd-subtract-based modular multiplication to save logical resources.Secondly,the thesis uses the ARM processor to configure hardware logic related registers,and relies on the Lw IP stack to design and implement a self-defined Ethernet sending function to realize ciphertext data transmission at the application layer.In addition,it also uses a serial port and a PC terminal to achieve key data interaction.Finally,this thesis builds a test environment and designs experiments to perform functional verification and performance analysis on various modules of the transmission system.The results prove that the transmission system functions are normal and can realize lossless compression,encryption and transmission of data.The Ethernet transmission rate used is up to 311 Mbps.The maximum throughput of the AES algorithm at 200 MHz can reach 1.34 Gbps.In conclusion,the data transmission system designed this time fulfills the intended function.