  We study the squeezing as well as the statistical properties of the output
radiation from a degenerate parametric oscillator coupled to a squeezed vacuum
reservoir employing the stochastic differential equations associated with the
normal ordering. It is found that the degree of squeezing of the output
radiation is less than the corresponding cavity radiation. However, for output
radiation the correlation of the quadrature operators evaluated at different
times also exhibits squeezing, which is the reason for quenching of the overall
noise in one of the quadrature components of the squeezing spectrum even when
the oscillator is coupled to a vacuum reservoir. Moreover, coupling the
oscillator to the squeezed vacuum reservoir enhances the squeezing
exponentially and it also increases the mean photon number.
