Non-linear stacking of signals

Stacking repeated records can improve the SNR of seismic, geo-radar, or NMR signals. Three methods of non-linear stacking are implemented.

Stacking repeated records can improve the signal-to-noise ratio (SNR) of seismic, geo-radar, or nuclear magnetic resonance measurements. Stacking usually employs a simple summation of amplitudes, but some procedures are also available based on non-linear stacking. Three methods of non-linear stacking are implemented as MATLAB functions:

1. The PWS (Phase-Weighted Stacks) method. It is based on the similarity of instantaneous phases on the corresponding complex signals.

2. The GAS (Generalized Average of Signals) method. It averages complex spectra in the frequency domain, employing the Generalized Average of Complex Numbers (GACN).

3. The CSA (Complex Signal Average) method. This method is based on complex averaging signals using GACN.

Non-linear stacking can improve the SNR by up to the first tens of dB. The advantages of time-domain methods PWs and CSA are their lower computational complexity and the fact that they do not depend on the choice of the computation window length compared to GAS.

Demo_script can be used with demo_data - downloade here.