GPR surveying over burial mounds: correcting for topography and the tilt of the GPR antenna
D. Goodman, H. Hongo, N. Higashi, H. Inaoka and Y. Nishimura
Issue: Vol 5, No 6, December 2007 pp. 383 - 388
Special Topic: Archaeogeophysics
Info: Article, PDF ( 7.62Mb )
A new method for static corrections of radargrams, which accounts for the tilt that the GPR antenna encounters on sites with topography, has been developed. The method uses the average electromagnetic wave velocity and assumed antenna tilt according to the first derivative of the topography profile, in order to adjust the normal ray projecting from the GPR antenna into its correct subsurface location. Static tilt corrections for radargrams with under sampled scan locations can be effectively adjusted using scan sweeping across small angles. Radargrams that are corrected for topography and antenna tilt show that changes in the imaged locations of subsurface structures can be significant, resulting in improved focusing and more accurate positioning of reflections.