Development Of Multi-channel VHF Remote Control Communication System

Very High Frequency (VHF) radio communication is the most important air-ground communication in the modern civil aviation. With the rapid development of China’s civil aviation VHF communications become increasingly busy.For the rational use of frequency resources, and for minimizing the number of radio erection, air traffic control departments utilize Voice Switching and Control System to make VHF radio resources efficiently shared.Voice Switching and Control System is complex and expensive, which causes much financialstress to the air traffic control departments of some small and medium-sized airport. This paper explains the design and development of a "multi-channel VHF remote communication system". This system has the main function of the voice switching and control system, and it is safe, reliable, and low cost. It provides an economical and practical solution forthe air traffic control departments.This article discusses the various stages of the research in accordance with the project developing process.First, the author conducts a system requirements analysis after an industry analysis, and auser research.Based on the analysis,the author clarifies its market position as a backup system or emergency system for Voice Switching and Control System, proposes potential innovative features, such as reminder function, upstream VHF equipment monitoring function, and etc., and suggests the technical developing directions for circuit-switched technology and embedded development.Secondly, followed by the analysis of the relevant technology, the author designs the overall project in both hardware and software. The system’s hardware development includes the central control unit and user terminals.In the central control unit, the C8051F120MCU is used to control CD22M3494matrix switch dedicated chip to make voice crossing functional; uses C8501F120single chip for sampling, uses CP2200as ethernet interface, convert R&S private protocol to UDP.The user terminal uses the hardware of embedded system based on ARM11。As to system software, the author establishes overall system model, and establishes the system’s operating environment and software development environment.Finally,in the form of illustrations to describe the concrete realization of the system monitoring software and user terminal software. The MVC model is used for software development, separate view from model, obtain the maximum code reuse. In software program, make full use of the signals and slots mechanism in Qt, can overcome the difficulties that other development kit use callback mechanism bring type safety shortcomings and strong coupling. In the development of terminal software, the use of the cross-compiling technology to improve the efficiency of programming.From prototype testing and trial,the various indicators of the system are in line with the Civil Aviation related standards, and the various functions meet the design goals. This system has strong security and stability, and has promising practical application prospects.