Full-duplex bidirectional data transmission link using twisted lights multiplexing over 1.1-km orbital angular momentum fiber

Abstract

We present a full-duplex bidirectional data transmission link using twisted lights multiplexing over 1.1-km orbital angular momentum (OAM) fiber. OAM+1 and OAM-1 modes carrying 20-Gbit/s quadrature phase-shift keying (QPSK) signals are employed in the downlink and uplink transmission experiments. The observed mode crosstalks are less than-15.2 dB, and the full-duplex crosstalks are less than-12.7 dB. The measured full-duplex optical signal-to-noise ratio (OSNR) penalties at a bit-error rate (BER) of 2 × 10-3 are ∼2.4 dB in the downlink transmission and ∼2.3 dB in the uplink transmission. The obtained results show favorable full-duplex twisted lights multiplexing data transmission performance in a km-scale OAM fiber link.