A new grounded precious experimental method is proposed for identifying signal-induced noise (SIN) originated in the photoelectric detector, as well as establishing a fine structure SIN model for its deduction from raw Lidar signals. The method of data process of a dual-wavelength Rayleigh scattering lidar with multi-channels enrolled in the meridian project is improved. Temperature profiles obtained by calibrated data show the coincident distribution with the TIMED satellite over the altitudes of 35 km to 85 km, temperature bias between them is less than 5 K from 30 km to 55 km, less than 10 K from 55km to 75 km.