Ground-Based Doppler Asymmetric Spatial Heterodyne Interferometer: Instrument Performance and Thermospheric Wind Observations

The thermosphere serves as a pivotal region for Sun–Earth interactions, and thermospheric winds are of great scientific importance for deepening insights into atmospheric dynamics, climate formation mechanisms, and space environment evolution. This study designed and developed a Ground-based Doppler Asymmetric Spatial Heterodyne Interferometer (GDASHI). Targeting the nightglow of the oxygen atomic red line (OI 630.0 nm), this instrument enables high-precision observation of thermospheric winds. The GDASHI was deployed at Gemini Astronomical Manor (26.7°N, 100.0°E), and has obtained one year of nighttime meridional and zonal wind data. To verify the reliability of GDASHI-derived winds, a collocated observation comparison was performed against the Dual-Channel Optical Interferometer stationed at Binchuan Station (25.6°N, 100.6°E), Yunnan. The winds of the two instruments are basically consistent in both their diurnal variation trends and amplitudes. Further Deming regression and correlation analysis were conducted for the two datasets, with the meridional and zonal winds yielding fitting slopes of 0.808 and 0.875 and correlation coefficients of 0.754 and 0.771, respectively. An uncertainty analysis of the inter-instrument comparison was also carried out, incorporating instrumental measurement uncertainties, instrumental parameter errors, and small-scale perturbations induced by observational site differences; the synthesized total uncertainties of zonal and meridional winds are determined to be 20.24 m/s and 20.77 m/s, respectively. This study not only verifies the feasibility and reliability of GDASHI for ground-based thermospheric wind detection but also provides critical observational support for analyzing the spatiotemporal variation characteristics of mid-low latitude thermospheric wind fields and exploring their underlying physical mechanisms.