Abstract
We report on the generation and transmission of 30 GHz millimeter-wave (MMW) beat-tone signals employing external- (EIL) and self-injection-locked (SIL) InAs/InP quantum-dash based dual-wavelength laser (QD-DWL) sources emitting in mid L-band. Later, successful transmission of 2 Gbps quadrature phase-shift-keying (QPSK) signal over clear weather conditions on 2 m wireless (WL), and hybrid channels consisting of 20 km single-mode fiber (SMF) and 2 m WL, and 20 km single-mode fiber (SMF), 5 m free-space-optics (FSO) and 2 m WL, are demonstrated employing both MMW sources, with a slight similar to 1.4 dBm extra received optical power requirement from SIL QD-DWL. Lastly, examining the effect of dusty weather conditions on the MMW transmission over 20 km SMF, 0.9 m FSO and 1 m WL hybrid channel, considering both EIL and SIL sources, showed maximum visibility range (V) of 12 +/- 2 m and 16 +/- 2 m for successful transmission, respectively. These investigations reinforce the simple, cost-effective, and energy-efficient SIL QD-DWL as a candidate L-band millimeter-wave (MMW) source compared to the EIL counterpart in 5G and next-generation radio-over-fiber wavelength-division multiplexing networks.