Quantum-Dash Laser-Based Tunable 50/75 GHz mmW Transport System for Future L-Band Networks

Tunable 50/75 GHz millimeter wave (mmW) transmission system has been demonstrated employing self-injection locked quantum-dash laser diode comb source (SIL QDCS) in the challenging 1610 nm region. The generated 50/75 GHz mmW beat-tones exhibited low phase noise of −64 dB/Hz at 1 kHz offset and narrow radio-frequency (RF) linewidths of ~1 kHz at the transmitter end. A 4 GBd (8 Gb/s) quadrature phase-shift keying (QPSK) data stream is successfully transmitted over both mmW carriers and across various channels viz. 2 m wireless (WL) link, 11.6 km single-mode-fiber (SMF) – 2 m WL link, and 11.6 km SMF – 6 m free-space-optics (FSO) – 2 m WL link, thus affirming the potential of quantum-dash laser diode (QDLD) in high-frequency mmW applications. This work is a potential step towards realizing next-generation high-frequency tunable mmW optical-RF convergent hybrid networks operation in L-band, and one such possible proposal with a single QDCS is presented.