Modulation depth of static four-phase-divided wind imaging interferometer

The static four-phase-divided imaging interferometry is a new technology of passive detection for the upper atmospheric wind field. It is featured with real-time detection, no moving parts, stability, and so on. In this paper, its basic theory is discussed, and its characteristics are briefly introduced. Furthermore, its key technical parameter, modulation depth, is analyzed. The relationships of modulation depth with the incident angle and temperature of the working environment are derived by using computer simulation. It is shown that the modulation depth decreases with the increase of the temperature and incident angle. The study provides a theoretical basis to increase the modulation depth of the interferometer, and it is of significance for the development of the upper atmosphere detection technique and theory.