  The PAMELA satellite-borne experiment is providing first direct measurements
of Solar Energetic Particles (SEPs) with energies from $\sim$80 MeV to several
GeV in near-Earth space. Its unique observational capabilities include the
possibility of measuring the flux angular distribution and thus investigating
possible anisotropies related to SEP events. This paper focuses on the analysis
methods developed to estimate SEP energy spectra as a function of the particle
pitch angle with respect to the Interplanetary Magnetic Field (IMF). The
crucial ingredient is provided by an accurate simulation of the asymptotic
exposition of the PAMELA apparatus, based on a realistic reconstruction of
particle trajectories in the Earth's magnetosphere. As case study, the results
of the calculation for the May 17, 2012 event are reported.
