Design Of User Terminal Software Of HF Frequency Selection And Link Establishment System

As a radio communication with the longest history, HF communication has advantages of simple equipment, flexible networking and low cost, and since its media is ionosphere, it is easily to avoid artificial interruption. So HF communication has an irreplaceable position in the field of communication, especially the military communication.The research of this paper is derived from the project named as “The Research of HF Frequency Selection and Link Establishment Technology”. The project is to design and implement a new HF communication system with the fast and reliable adaptive frequency selection and automatic link establishment. The system mainly includes three parts: user terminal, communication controller and channel machine. The system software which is applied in the user terminal is designed and implemented in this paper, named as user terminal software. It includes frequency selection module and human-computer interaction. The major contributions of this paper are outlined as follows:(1) The system of HF frequency selection and link establishment is briefly analyzed. Firstly, the hardware system is researched, including the main function of every component and the work procedure of the whole system. Then, the system’s software architecture is analyzed, and its functions in application layer, link layer and physical layer are given respectively.(2) In the system, the user terminal controls the communication controller by network interface to accomplish the corresponding communication business. Therefore, the interface between them is researched and a set of regulations of network interface is designed, which provides the form of frame according to which user terminal and communication controller send, receive and deal with the data, including data frame and interface command frame.(3) On the basis of the operational principle and functional requirement of the system, the user terminal software is designed and implemented. Firstly, the design scheme andworking procedure of every module of the system is analyzed, including the system’s initialization module, frequency selection module, link establishment module, data transmission module and the storage and analysis of data module, with the emphasis on the frequency selection module which includes point-to-cover frequency selection and point-to-point frequency selection. Then, based on the analysis and research, the user terminal software is designed and corresponding functions are accomplished. At last, the system’s human-computer interaction is designed and the idea of design is analyzed. The interface is integrated, visualized and easily to be operated.(4) In the system, the user terminal controls the communication controller to accomplish automatic link establishment. Therefore, the link establishment function of this system should be tested and verified. At the end of this paper, some test programs of user terminal are designed and completed by multithread technology, including the test scheme and test procedure of blind link service, LQA service, link establishment service.