Source Calibration Using Variable Projection Method in Frequency-domain Full-waveform Inversion

We applied a source calibration scheme based on variable projection for frequency-domain full-waveform inversion. This scheme directly links the simulated data with the measured data without requiring additional unknowns in the inversion. The source waveform is updated automatically in each iteration based on a least-squares minimization. By using this scheme we can develop a robust source-independent full waveform inversion algorithm. This calibration method can straightforwardly be applied for other applications such as electromagnetics.