Atc Vhf Signal Chebyshev Filter And Implementation

Nowadays, higher demand for the technical level of air traffic control has been put forward with the rapid development of civil aviation. Currently, the main means of communication between the pilot and the controller are VHF, HF and shortwave. On one hand, because of the rapid increase of air traffic flow in recent years, coupled with sharp increase in the number of radio stations, the electromagnetic environment has deteriorated to the air traffic management VHF communications environment a lot of negative factors; on the other hand, due to the rapid increase of air traffic flow, the controllers have been more and more dependent on the devices than ever before. Under the pressure of high flow rate in the current, the failure of communication is unacceptable. The ATC VHF signal will be affected by the noise during the long transmission path. It becomes the hot topic of the VHF communications equipment manufacturers and maintainer to reduce the noise effect and improve the VHF communications voice quality.The signal analysis and digital signal processing theories has been intrduced in the paper through the discuss of the application and transmission of VHF signal in the air traffic management. And also the frequency spectrum has been analyzed in the paper. Some filter has been chosen to be compared with. According to the signal analysis and filter comparison, Chebyshev filter for VHF sigal based on the MATLAB programming has been selected as the filter of VHF sigal and has been realized. At the same time, the filtered signal has been discussed in the paper. MATLAB has been chosen as the tool to realize the filter. Considering that the MATLAB has some disadvantages such as low speed, poor real-time character, unable to run independently. As a matter of fact, C/C++ has many advantages like high speed and able to run independently. According to the analysis of MATLAB and C/C++, the article introduced the MATLAB and C/C++ mixed programming method by which the powerful mathematical tool of MATLAB and the efficient procedures speed of C/C++ has been combined. The MATLAB and C/C++ mixed programming method has solved the problem of low running efficiency of MATLAB. At the end, the essay has discussed and analyzied the results of signal filtering which illustrates the rationality and feasibility of selecting the Chebyshev filter to process the VHF signal based on MATLAB and C/C++ programming. The method of signal processing and programming introduced in the paper provided an idea and laid a foundation for the further specific application.