The Simulation Measurement Experiment And Calibration For Solar Total Irradiance Monitor On Board

STIM (Solar Total Irradiance Monitor) can be used on sun-synchronous polar orbit weather satellites to measure the total solar irradiance. It contains three independent and identical wide view absolute radiometers. They are mounted on the satellite in an angle which ensure the sun scan over the field of view of the absolute radiometers. This measurement method doesn't need the instrument tracking the sun but the sun scan over the field of view of the absolute radiometers in each orbit cycle. The paper presents the measurement method of simulation for solar irradiance measurement and calibration by mounting the instrument on a two-axis rotation table. By controlling the rotation angle velocity of the instrument in the meridian direction being the same as that of the weather satellite's on orbit, we can measure the solar irradiance when the sun scan over the field of view of the absolute radiometers to simulate the onboard state. And we have operated the measurement with the prototype of STIM. The SIAR-1 is traceable to WRR and serves as a transfer standard. So simultaneous comparison measurements between SIAR-1 and each of the three wide view absolute radiometers are measured to provide calibration corrections to the instrument. And we have a further study at the influence of stray light to the measurement results. This paper presents the method of simulation experiment and calibration for solar irradiance measurement with Solar Total Irradiance Monitor on board.