Programmable Asic / Dsp-based High-precision Spectrum Analysis

With the rapid development of railway construction,especially, after implementing speed-raising five times in railway transportation, the traffic management of modern intellectual railway becomes a subject to be solved urgently. The traditional artificial signal lamps already can't meet the demand of the train speed-raising, therefore we need to control the trains in the way of setting up different signal frequency in different sectors.In order to make sure the control toward the locomotives, the trains in the work constantly identify signal frequency to obtain relevant control information. The trains deal with real-time information which is obtained from identifying signal frequency, its own position, railroad condition and so on, command the locomotive to go normally, prevent the traffic accident from happening. For this, the article has done some primary research on the aspect this question — the information recognition technology in the traffic administration of railway and made a certain achievement.This article introduces a high-accuracy spectral analytical method based on programmable ASIC/DSP and does some research from 3 parts as follows: First, research on the method of FFT is done deeply,and we put forward a concrete method based on DSP and a FFT operation point which can meet the need of the frequency identified accuracy.That is,the rate of spectral distinguishability can be improved to meet the demand of 0.1hz through 4096-point-FFT; Second, The developing platform of hardware electric circuit, included programmable ASIC chip developing circuit,was designed to accomplish high accuracy frequency detecting.The circuit provides various logic control,MCU provides an assistance function and DSP completes the FFT operation; Third, application program analyzed by FFT frequency spectrum, was complied with assemble language in ccs developing system, and the resule of simulation has reached the high accuracy request of each frequency whicn can be identified accurately.The research achivement has accomplished the design of recognition system of information in the traffic management of railway. It has higher applied value in the development , application and further research of information processing technology in the control system of the railway.