The Design,Optimization And Implemention Of RFID Antenna In Train Control System

With the rapid development of Chinese high-speed railway technology,our country has made remarkable achievements,and high-speed train has been at the leading level in the world.With the improvement of the standard limiting of train speed,the requirements and standards of the signal communication and control system are also more stringent.As the equipment of near-field sensing communication with balise,the performance of the BTM signal antenna has a direct impact on the circuit of balise and demodulation and decoding in BTM.This paper,starting from the principle of RFID near-field sensing,will apply the method to the design of the BTM FSK signal antenna.Through the combined method of theoretical calculation,electromagnetic simulation,and debugging of impedance matching,this paper provides a complete set of design process.At the same time,considering the practical application environment of the antenna,this paper also provides and analyses the simulation of different environment effects on transmission characteristics of antenna in balise and tansmition module in train.Therefore,this paper,rooting in the laboratory project,has completed the following work:1.Starting from the RFID technology,this paper introduced the principle and components of the RFID module,studied and analyzed the specific application of the system-train balise system.2.This paper carried out theoretical analysis of the antenna field,and studied near-field-sensing area which is specifically applied in paper.After that the paper constructed electromagnetic emulation model of balise antenna and combined the theoretical calculation with the simulation of HFSS electromagnetic properties,which obtain the distribution of magnetic field intensity.Based on this,the paper carried on the detailed analysis and the simulation of the BTM antenna and got the size parameters and electromagnetic simulation model which reached the optimal condition of performance.3.From the perspective of practical application environment of train-controlled transponder system,the paper found out changes of transmission characteristics of the antenna in several common cases,including lossy material such as snow and water,as well as metal material.4.The paper analyzed and compared the characteristics of common impedance matching circuits.Combining with the antenna characteristics and application requirements in this design,the paper completed its theoretical design through the derivation and theoretical calculation.5.With the use of Cadence circuit design tools,the paper complete the PCB board design of receiving antenna for subsequent physical verification and testing.And impedance matching circuit was also added to the PCB design,as well as the experiment of impedance matching.By using a combination of methods of theoretical calculation,simulation analysis and PCB board test,this paper completed the design and implementation of the BTM antenna of 27MHz and 4MHz,which achieved the good performance of the state.This can effectively improve the accuracy of the demodulation and decoding circuit,which is of great practical significance.