We experimentally demonstrate a monitoring technique for determining misalignment between the in-phase/ quadrature (I/Q) data streams and between the data and pulse carving in an 80 Gb/s serial-type return-to-zero differential quadrature phase-shift-keying (RZ-DQPSK) transmitter. By measuring optical clock tone power and the radio frequency (RF) clock tone power, a monitoring-power-dynamic-range (MPDR) of 8 dB is obtained for I/Q data misalignment and 6 dB for data/pulse carving misalignment.
Citation: IEEE Photonics Technology Letters
Pub Type: Journals
fiber optics communications, return-to-zero differential quadrature phase-shift-keying (RZ-DQPSK), synchronization monitoring