Synchronization of a $40\mathrm{GHz}$ quantum-dash mode-locked (ML) Fabry–Perot laser diode with optically injected pulse streams is experimentally studied. Injected signals consist of nonmodulated and modulated trains of $1.6\mathrm{ps}$ pulses at various repetition rates, ranging from 10 to $160\mathrm{GHz}$ and 10 to $160\mathrm{Gbps}$ , respectively. Subharmonic, fundamental, and harmonic synchronization of the ML laser allows retrieval of stable $40\mathrm{GHz}$ clock pulses featuring a width of $1.8\mathrm{ps}$ . Frequency components at 10 and $20\mathrm{GHz}$ do not create any amplitude modulation on the recovered $40\mathrm{GHz}$ clock pulses when injecting signals at 10 and $20\mathrm{GHz}/\mathrm{Gbps}$ . In addition, external synchronization of the laser with pulse streams at 80 and $160\mathrm{GHz}/\mathrm{Gbps}$ is sustained despite the absence of significant components at or below $40\mathrm{GHz}$ .