Research On Signal Data Acquisition Of Fourier Transform Spectrometer

Fourier transform spectrometer (abbreviated FTS) is a powerful spectralinstrument. With such advantages as multiplex channels, great energy throughputand high resolution, it plays a significant role in the field of near infrared and visiblewaves. This paper focuses on the data acquisition system which is one of the keytechnologies of the Fourier Transform Spectrometer.Firstly, the history of Fourier Transform Spectrometer and the current situationand development trend in the near-infrared and visible waves are researched in thispaper. Then signal-to-noise ratio of Fourier transform spectrometer based on how itworks is analyzed.This paper also introduces the theoretic analysis of the equal optical pathdifference distance sampling compared with the equal time distance sampling. Basedon the analysis of the dynamic range of interferogram, the minimum resolution of anADC is estimated. As the laser interferometer signal frequency is smaller thansampling pulse frequency needed, a digital frequency multiplier is designed.This paper presents multi-channel interferogram synchronous acquiringsystem’s implementation process in detail, including the data acquiring controlmodule based on FPGA,4-channel analog-digital conversion module, the datatransferred to PC hardware circuits, and corresponding software system.Testing methods and process of the multi-channel interferogram synchronousdata acquiring system, part of the test results and the result analysis are given in thispaper.The result in this paper shows that the project of multi-channel interferogramsynchronous acquiring system in this subject is feasible. The research results havegreat reference value to in-depth study of the interferogram acquiring technique inthe near-infrared and visible waves.