System and method for recovering a signal of interest from a phase modulated signal using quadrature sampling

A digital receiver system is used to recover a signal of interest, such as a measurand signal, from a phase modulated signal detected from a system utilizing quadrature carriers, such as a fiber optic interferometer sensor system. The digital receiver system includes a quadrature sampling demodulator that samples the phase modulated signal by using quadrature sampling periods to recover the odd and even components of the signal of interest. The digital receiver system can be used with an interferometer sensor system having an array of sensors that multiplex the measurand signals, e.g., using time or wavelength division multiplexing. Sampling with quadrature time samples provides a spacing in time between the samples that allows additional sensors to be multiplexed.