Design And Implementation Of HF Frequency Selection Communication System Software

What this thesis researches is derived from the laboratory's research project,Intelligent HF Communication System,which aims at designing and implementing a type of HF communication System with the functions of frequency selection,link establishment and data transmission,the design and development of which are presented.The main work of this thesis are summarized as following:1.The system architecture and the hardware components are analysed,and the work principle of the data link layer protocol is researched,and the overall framework of system software is designed.There are five main modules in HF communication system: frequency selection module,link establishment module,data transmission module,frequency updating module and data management module.2.The function of frequency selection module is based on historic data to predict the optimum working frequency.A frequency quality prediction model which is based on support vector machines is established,in order to improve the classification performance of which,an orthogonal genetic algorithm based on gene collection is proposed.At the same time,in order to improve the prediction accuracy,a quadratic prediction method is designed.The simulation results show that the model has a high accuracy and a strong generalization ability.3.The entire system software is designed and implemented.in short,the link establishment module includes Blind Linking,Quick Blind Linking,Blind LQA,LQA,and Calling;The data transmission module includes single frequency data transmission,dual frequency data transmission,adaptive transmission,and breakpoint resume;frequency updating module includes detecting frequency updating,predicting frequency updating,and LQA frequency updating.The frequency selection module acts as a stand-alone module that is called by other modules.In order to improve the efficiency of link establishment,a function called Quick Blind Linking is designed in the link establishment module,and the frequency of the establishing link is given by the frequency selection module.In order to improve the efficiency of the frequency updating,the frequency of detection in the detection frequency updating and predictive frequency updating are provided by frequency selection module.In the data transmission module,in order to improve the throughput of data transmission under the premise of ensuring reliability,the functions of adaptive rate mechanism,dual frequency data transmission,and breakpoint resume are designed.The dual frequency data transmission adopts the idea of frequency diversity.In addition,in order to automate data management,data management and analysis module is designed to sort and organize data,generate reports automatically,and provide data visualization interfaces to facilitate users' intuitive understanding of current channel conditions.4.The system software was tested and verified on the indoor test platform and in the actual outdoor circuit test.The results of test show that the system software is stable and reliable,which can complete the functions of frequency selection,link establishment and data transmission,and the test also verifies the validity of the frequency selection module.The laboratory's scientific research project has completed several user-specified circuit tests,reaching the user's requirements,and the final delivery of the project is ongoing.