Design and Simulation Results Analysis of a Spaceborne Fabry–Perot Interferometer for the Near-Space Atmospheric Wind Field

Currently, there are relatively few spaceborne methods for detecting near-space atmospheric wind fields, and the Fabry–Perot Interferometer (FPI) is one of the more important and widely used detection techniques. To address the gap in China’s space-based FPI wind sensing capabilities, the National Space Science Center developed a spaceborne FPI wind interferometer. This paper mainly introduces this instrument’s optical design, structural design, thermal control design, optical simulation, and result analysis. First, the optical design is discussed based on the wideband detection requirements, and the imaging system’s image quality is evaluated. Then, based on optical simulation data, wind speed inversion and accuracy analysis of the spaceborne FPI instrument are conducted. The wind speed errors at the 557.7 nm and 762.0 nm bands are –1.722 m·s^–1 and –2.3672 m·s^–1, respectively, indicating that the spaceborne instrument design meets the wind measurement requirements. Then, the key points of the instrument's structural design and the thermal control solution for the imaging part are presented, along with a translational filter switching device driven by a trapezoidal lead screw and a micro gear stepping motor or micro linear motor. The paper also explores the relationship between the temperature control accuracy of the instrument’s core components (the etalon) and wind measurement errors. A combined active and passive design is adopted to minimize the impact of temperature fluctuations on the results, which is verified with simulation results.