  We study the representations of the three-dimensional Euclidean Snyder-de
Sitter algebra. This algebra generates the symmetries of a model admitting two
fundamental scales (Planck mass and cosmological constant) and is invariant
under the Born reciprocity for exchange of positions and momenta. Its
representations can be obtained starting from those of the Snyder algebra, and
exploiting the geometrical properties of the phase space, that can be
identified with a Grassmannian manifold. Both the position and momentum
operators turn out to have a discrete spectrum.
