Simple scheme for PDM-QPSK payload generation in an optical label switching network

We propose and experimentally demonstrate a novel and simple scheme for dual-polarization vector pay-load generation in an optical label switching network. The 8 Gbaud quadrature-phase-shift-keying (QPSK) payload, generated by one intensity modulator with signal precoding and optical carrier suppression, is first polarization-multiplexed by a polarization multiplexer, then combined with a 2.5 Gb/s label before being transmitted over 20 km single-mode fiber, and finally separated from the label and recovered by the receiver with less than 2 dB power penalty. The proposed scheme can facilitate label insertion and is suitable for an optical label switching network with a simple architecture.