  Propagation graphs (PGs) serve as a frequency-selective, spatially consistent
channel model suitable for fast channel simulations in a scattering
environment. So far, however, the parametrization of the model, and its
consequences, have received little attention. In this contribution, we propose
a new parametrization for PGs that adheres to the doubly exponentially decaying
cluster structure of the Saleh-Valenzuela (SV) model. We show how to compute
the newly proposed internal model parameters based on an approximation of the
$K$-factor and the two decay rates from the SV model. Furthermore, via the
singular values of multiple-input multiple-output (MIMO) channels, we compare
the degrees of freedom (DoF) between our new and another frequently used
parametrization. Specifically, we compare the DoF loss when the distance
between antennas within the transmitter and receiver arrays or the average
distance between scatterers decreases. Based on this comparison, it is shown
that, in contrast to the typical parametrization, our newly proposed
parametrization loses DoF in both scenarios, as one would expect from a
spatially consistent channel model.
