Finite velocity planar random motions driven by inhomogeneous fractional   Poisson distributions
  In this paper we study finite velocity planar random motions with an infinite number of possible directions, where the number of changes of direction is randomized by means of an inhomogeneous fractional Poisson distribution. We first discuss the properties of the distributions of the generalized fractional inhomogeneous Poisson process. Then we show that the explicit probability law of the planar random motions where the number of changes of direction is governed by this fractional distribution can be obtained in terms of Mittag-Leffler functions. We also consider planar random motions with random velocities obtained from the projection of random flights with Dirichlet displacements onto the plane, randomizing the number of changes of direction with a suitable adaptation of the fractional Poisson distribution. 
R. Garra, E. Orsingher
math.PR