THE USE OF FFT TECHNIQUES IN PHYSICAL GEODESY

The fast Fourier transform (FFT) technique is a very powerful tool for the efficient evaluation of gravity field convolution integrals. It can handle heterogeneous and noisy data, and thus presents a very attractive alternative to the classical, time consuming approaches, provided gridded data are available. This paper reviews the mathematics of the FFT methods as well as their practical problems, and presents examples from physical geodesy where the application of these methods is especially advantageous. The spectral evaluation of Stokes’, Vening Meinesz' and Molodensky's integrals, least‐squares collocation in the frequency domain, integrals for terrain reductions and for airborne gravity gradiometry, and the computation of covariance and power spectral density functions are treated in detail. Numerical examples illustrate the efficiency and accuracy of the FFT methods. Copyright © 1990, Wiley Blackwell. All rights reserved