Detection of nonclassical oscillations in phase space by cascaded optical homodyning

We discuss a recently proposed scheme for the reconstruction of the quantum state of a one-mode traveling light wave. In the cascaded homodyning schem e the balanced and unbalanced principles of homodyning are combined. We pre sent here a derivation of the universal sampling function by inverting the Radon transformation occurring in the second stage of the setup. The sampli ng function possesses a simple structure, which is independent of the locat ion of the phase-space point. This latter property makes it a promising too l for detecting nonclassical oscillations in quasiprobability functions.