Fig. 1. Basic principle of greenhouse gas detection using array F-P interferometer

Fig. 2. Schematic diagram of working principle of array F-P interferometer

Fig. 3. Schematic diagram of atmospheric transmission path

Fig. 4. Relationship between the amplitude of Fourier expansion term coefficient and reflectivity of interference cavity

Fig. 5. Interference signals collected by array F-P interferometer

Fig. 6. Upward radiation absorption characteristics of the atmosphere under different greenhouse gas volume fractions. (a)(c) CO2 and its detailed figure; (b)(d) CH4 and its detailed figure

Fig. 7. Relationship between interference signal and greenhouse gas volume fraction. (a) CO₂; (b) CH₄

Fig. 8. Relationship between detection sensitivity and optical path difference. (a) CO2 signal; (b) CH4 signal

Fig. 9. Relationship between integral sensitivity and optical path difference. (a) CO2 signal; (b) CH4 signal

Fig. 10. Relationship between detection sensitivity and reflectivity of interference cavity. (a) CO2 signal; (b) CH4 signal

Fig. 11. Relationship between signal-to-noise ratio and reflectivity of interference cavity. (a) CO2 signal; (b) CH4 signal

Fig. 12. Relationship between normalized sensitivity and reflectivity of interference cavity

Fig. 13. Relationship between spectral resolution and reflectivity of interference cavity

Fig. 14. Relationship between optical sampling range difference and integral sensitivity and F-P number

Fig. 15. Relationships between detection sensitivity of carbon dioxide system and sampling interval of adjacent F-P optical path difference. (a) Δ=λ_centre; (b) Δ=λ_centre/4; (c) Δ=λ_centre/6

Fig. 16. Relationships between detection sensitivity of methane system and sampling interval of adjacent F-P optical path difference. (a) Δ=λ_centre; (b) Δ=λ_centre/4; (c) Δ=λ_centre/6

Fig. 17. Relationship between sampling range of optical path difference and integral sensitivity and sampling interval （λ_center/a） of adjacent F-P optical path difference