Wavelets (Jun can comment on this)

• wavelet transform coherency test (Garrison 2011) used to compare different receivers
• wavelet transforms from different satellites seem to be too different / varying to isolate signatures (see next slide)

After they do wavelet analysis, they apply bandpass filter to TEC and perform cross correlations

I just did this for different bands

G04

G26

G27

G31

G04 and G26 is our best bet for seeing cross-correlation features

disturbance distance based on 150 m/s propagation ground speed

G04 TEC segment (orange)

segment correlation with G06 TEC after applying different bandpass filters

CONCLUSION:

it's hard to fit in one slide, but looking really closely, there aren't any isolated signatures from during the earthquake period