Design Of DME Receiver Module Of Responder Based On FPGA

With the development of China's aviation industry,multi-mode navigation system is becoming increasingly widespread.How to realize the miniaturization and intellectuali-zation of the land-based radio navigation equipment has become an important research direction in the field of radio navigation.DME is an important land-based radio navigation system can provide the slant distance for aircraft to the air station.DME is composed of ground station and airborne equipment.Receiver module of responder is the core device for the ground station,its main functions are to complete the receiving and processing the signal from aircraft.At present,receiver module of responder in most active service ground stations are designed by the separation components circuit,they are complex and difficult to control,high cost of improvement and maintenance.In view of these problems,the receiver module of responder is designed by using the programmable logic device to complete its main functions in this thesis.In this thesis,firstly,analysing functional requirements and performance indicators of receiver module,that is according to the requirements of the People's Republic of China Civil Aviation Industry Standard.Then,an overall design scheme of the receiver module is proposed and finish the selection of the main components.In this thesis,circuit design is based on FPGA,which includes AD converter circuit,level converter circuit,interface circuit and power circuit,and finish PCB design of them.According to the characteristics of DME signal,coding and decoding mode of the signal,working principle of the ground station,the program design is mainly to finish the signal half amplitude point detection module,sensitivity control module,echo suppression module,decoding and coding module,ground station identification code generation module,random pulse filling module and signal priority module.At last,the whole module is debugged and tested.The test results show the design of the receiver module in this thesis can meet the design requirements under the indoor test environment.In this thesis,the design of the receiver module of responder has a good flexibility in the application,which lay a good foundation for the following function expansion and the miniaturization,and improve the signal processing speed and reliability.