Covariance functions of GRFs

• For a stationary, isotropic GRF we have that $Corr(h) = \frac{C(h)}{\sigma^2}$
• In practice, the correlation function $Corr(h)$ is defined (positive definite function) and the covariance function is derived as $C(h) = Corr(h) \cdot \sigma^2$