Technique for Reduction of Coherence Function Bias Error
W.T. King · IEEE Transactions on Nuclear Science · 1985
The bias error in the coherence function is found to arise from the calculation of the square magnitude of the cross-power spectral density when the real and imaginary components are not converged. Therefore, the bias error of the coherence function can be decreased significantly without averaging more data blocks if the variance of the real and imaginary components are reduced by fitting the spectra of these separate components to an appropriate model.