基于单片机的车载应答器设计
毕业论文关键词： 应答器；应答器传输模块；单片机；射频；车载天线
The design of vehicle transponder based on SCMAbstract: With the development of science and technology and fast step of life, the train speedhas also been improved, in order to solve the problem of insufficient continuous information,the vast majority of developed countries ATP railway system on the 160km / h or more lines invarying degrees, use the point transponder device. In the railway, the balise system includesground transponder, trackside electronic unit (LEU) and vehicle-mounted Balise TransmissionModule (BTM), the study of this issue is mainly vehicle balise, including a balise transmissionmodule BTM and car antenna design, based on car balise transmission mode, the use ofrelevant knowledge to design a microcontroller-based automotive balise which can achievehigh frequency electromagnetic energy sent to the ground floor to activate the baliser andreceiving information from the ground and variable information and other basic functionsterrestrial balise sent. The design focuses on the balise transmission module BTM circuit, Selecting the AT89C51 as MCU control circuits,choosing MC2833 and MC13055 to receiveor sent FSK signal respectively.To design a high performance antenna, the car antenna isoptimized by comparing the antenna material, size and shape.
Keywords：balise； BTM；MCU；RFID；vehicle antenna
目录
1 引言1
1.1 本课题的目的和意义· 1
1.2 发展趋势·1
2 车载应答器构成及原理·2
2.1 车载天线·2
2.2 应答器传输模块BTM3
3 国内外应答器系统的比较与分析 4
3.1 欧洲应答器的应用·4
3.1.1 欧洲应答器系统构成· 5
3.1.2 欧洲应答器技术指标· 5
3.2 国内应答器系统简介· 6
3.2.1 国内应答器系统构成· 6
3.2.2 报文编码·6
3.3 国内外应答器系统的比较与分析· 8
4 车载应答器系统的设计 9
4.1 车载天线·· 10
4.1.1 天线材质的选取·· 12
4.1.2 天线导体半径·· 12
4.1.3 天线的形状及尺寸··13
4.2 串行I/O口的设计 14
4.2.1 基于 MAX232 的电平转换·14
4.2.2 扩展串行接口··15
4.3 射频模块··16
4.3.1 MCU 控制电路 17
（1）中央处理器 17
（2）引脚排列及功能 17
4.3.2 射频收发部分··19
（1）射频发射模块 19
（2）射频接收及解调模块 20
4.4 信号的滤波··21
4.5 信号的译码··22