Calibration and Emitters Selection Method of Interferometer Based on Single or Double Emitters

Abstract

The traditional method of joint calibration of fixed baseline interferometer with multiple errors requires more than three calibration emitters to achieve real-time calibration of the interferometer in orbit, but the performance of the traditional method will be reduced or even failed when the number of calibration emitters is insufficient. For the situation that the number of calibration emitters is insufficient, a single or double emitters calibration method for fixed baseline interferometer is proposed. Under the condition of relative motion between the interferometer and the calibration emitters, a set of phase differences of calibration signals is obtained firstly by multiple measurements, and a set of equations about the systematic errors of the interferometer is listed by using the obtained phase differences, finally the systematic errors are solved by the Penrose inverse matrix assisted iterative least squares method. The simulation results verify the feasibility of the proposed method. On this basis, the influence of the emitter selection on the positioning performance of the interferometer after calibration is analyzed qualitatively by means of numerical simulation, decomposing the parameters of the emitter selection. The analysis results show that the calibration emitter located near the sub-star in the single emitter case or two calibration emitters located far apart both can make the interferometer obtain better positioning performance after calibration.

Keywords

• |interferometer|calibration|systematic error|single emitter|double emitters