Design And Implementation Of A Link Layer Protocol For A HF Link Establishment And Data Transmission System

With the continuous development of social science and technology,although various wireless communication methods emerge in an endless stream,HF communication still occupies an important position in the field of wireless communication with its own unique advantages.At present,various countries in the world are conducting more in-depth research on HF communication.In order to make HF communication adapt to more application scenarios,this paper designs and implements the remote control function and adaptive variable frequency data transmission protocol based on the HF chain construction data transmission bare metal system project,based on the HF chain construction data transmission ReWorks operating system project,completed The overall architecture design of the data link layer software and the simulation of the packet scanning protocol are presented.The main work done in this paper is as follows:1.Provides an overview of the overall design of the bare metal system.The hardware composition and overall software architecture of the bare metal system are given.2.In order to meet the needs of users for the remote control function,the remote control function is realized.The porting of the Lw IP protocol stack is completed.A remote control data security protocol is designed to ensure the security of data transmission in the network.According to the user data interface format between the host computer and the communication controller,the receiving and sending protocol of remote control service data is designed.3.In order to unify the data format in the data transmission process,a file preprocessing mechanism is designed.By designing the block cache mechanism,the transmission of large files is realized on the communication controller with limited memory resources.In order to improve the efficiency of data transmission,the adaptive speed change function is realized.On this basis,the adaptive frequency conversion function is designed,which can provide two adaptive frequency conversion methods according to the user’s needs.Improve the success rate of data transmission.4.The overall software architecture of the data link layer is redesigned on the ReWorks embedded real-time operating system.The software design of the peripherals required by the data link layer program on the ReWorks operating system is completed.The simulation of data link layer packet scanning protocol is implemented based on ReWorks operating system on X86 virtual machine.5.Set up an indoor test environment and an outdoor test environment,and test the remote control function of the bare metal system and the adaptive variable frequency variable frequency data transmission protocol.Through the analysis of the test results,the validity of the remote control function and the adaptive variable frequency variable frequency data transmission protocol is verified.A virtual test environment is built for the ReWorks operating system,and the packet scanning protocol is simulated on the X86 virtual machine,which verifies the correctness of the overall software architecture design of the data link layer on the ReWorks operating system.