Self-Coherent Multisymbol Detection of Optical Differential Phase-Shift Keying

This paper treats the recently emerging self-coherent multisymbol decision-feedback-aided detection techniques for optical differential phase-shift keyed (DPSK) transmission based on both an optical preprocessing approach and an electronic postprocessing approach. We present in detail i) the generation of a synthetic low phase-noise effective local oscillator out of the modulated optical data itself, and its estimation theory interpretation; ii) the role of polyphase (interleaved) DPSK in the optical preprocessing approach in easing the decision feedback realization requirements; iii) detection of M-ary DPSK modulation formats for general M, and differential quadrature phase-shift keying in particular; iv) three alternative integrated-optoelectronic receiver implementations for the optical preprocessing approach detailing the structures of the interferometric front-end and the high-speed electronic analog and digital building blocks; and v) the principle, and alternative implementations, of the digital postprocessing approach to self-coherent detection. We finally compare the capabilities of the emerging self-coherent detection and digital coherent detection techniques.