A 40nm CMOS single-chip 50Gb/s DP-QPSK/BPSK transceiver with electronic dispersion compensation for coherent optical channels

Optical communication technology in long-haul and metropolitan links is experiencing a transition to coherent techniques and high spectral efficiency modulation formats such as dual-polarization (DP) QPSK, DP-QAM and OFDM. The combination of coherent demodulation and DSP allows costly optical signal-processing hardware used to compensate fiber optic impairments such as chromatic dispersion (CD) and polarization-mode dispersion (PMD) to be replaced by DSP-based techniques [1]. Economic large-scale deployment of coherent systems requires the integration of the optical transceiver functions in CMOS technology.