High-sensitivity multi-channel single-interferometer DPSK receiver

A high-sensitivity method of demodulating wavelength-division-multiplexed optical DPSK channels using a single interferometer is described and demonstrated. We show that this technique can operate within existing standards and achieve near-quantum-limited receiver performance. The resulting hardware simplification has potential to reduce the cost of deploying and scaling future wide-band optical-communication networks employing WDM-DPSK.