Homodyne optical coherent systems based on polarization modulation

The first homodyne receiver for polarization modulated optical signals is proposed and analyzed. It is based on the detection at the receiver of the four quadratures that completely characterize the received optical field and on the estimation of the Stokes parameters starting from them. This allows homodyne detection to be carried out without phase locking the local oscillator to the received signal. An accurate performance evaluation is carried out both at the quantum limit and in the presence of phase noise for a binary system based on an antipodal decision in the Stokes space. The system structure is described. The quantum limit performance is evaluated, and the phase-noise induced penalty is evaluated using an accurate analytical model