This paper uses restriction of
Fourier transforms to construct explicit realizations of certain irreducible unitary
representations of SU(n,n). The realizations begin with generalizations of the
classical Szegö map. Boundary values of these Szegö maps naturally lead to certain
restrictions of Fourier transforms. The image of these restrictions provide concrete
constructions of unitary representations as L2 spaces on certain orbits. The SU(n,n)
invariance of the L2 spaces and inner products follows immediately from the
restriction maps and the natural pairing between certain degenerate principal
series.