基于嵌入式系统的ZFFT移频轨道检测算法

ZFFT Detection Algorithm of FSK Track Based on Embedded System

国产18信息轨道电路和UM-71系列无绝缘轨道电路是我国铁路的主流制式,其调制方式均为FSK(移频键控)。而准确快速测量调制频率是列车安全调度的首要条件。为提高信号频率检测的实时性和精度,检测算法设计中将欠采样技术应用到常规ZFFT算法中,实现软件程序的优化,提高检测速度。在基于DSP TMS320VC5402构建的检测平台上实现此算法。实验表明:此优化的ZFFT算法抗干扰性强,检测精度高,实时性满足实际要求。

18-information track circuits and UM-71 series jointless track circuits have become the dominant techniques for Chinese railway,featuring Frequency Shift Keying modulating pattern.The frequency of signal modulation is an important parameter for train security scheduling.To improve real-time capability and frequency detection accuracy,the under-sampling technology is applied in the traditional ZFFT algorithm,thus realizing the optimization of the software program and improving the detection speed of the algorithm.This algorithm is implemented on detection platform based on DSP TMS320VC5402,and the practical application indicates that the optimized ZFFT algorithm is of strong anti-interference ability,and could both improve the frequency resolution and meet real-time requirement of the system.