. Author manuscript; available in PMC: 2014 Mar 28.

Published in final edited form as: IEEE Trans Ultrason Ferroelectr Freq Control. 2010 Dec;57(12):2637–2653. doi: 10.1109/TUFFC.2010.1738

TABLE II.

Correlation Lengths Through Both Skulls (mm).

	300 kHz	500 kHz	600 kHz	700 kHz	800 kHz	900 kHz	1000 kHz
Human skull	47.5	27.4	—	18.2	—	10.6	—
Primate skull	—	—	34.3	27.8	20.3	17.9	13.4

Correlation lengths were estimated based on simulated data in the parietal bone. The correlation length decreases with frequency as the spatial variation of the skull thickness variation appears larger relatively to the wavelength; this is a sign of increased aberrations occurring with higher frequencies.