Reconfigurable Radar Waveform Generation Based on an Optically Injected Semiconductor Laser

We propose and experimentally demonstrate an approach to generating reconfigurable radar waveforms based on an optically injected semiconductor laser. In the proposed system, the semiconductor laser is operated at period-one oscillation state, in which an optical output signal containing a microwave modulation on the intensity is generated. After photo detection, a frequency-tunable microwave signal is obtained with its instantaneous frequency determined by the optical injection strength and/or the detuning frequency between the master and slave lasers. Since the dynamical behavior of a semiconductor laser evolves at a subnanosecond time scale, by properly designing a control signal to manipulate the optical injection strength, reconfigurable microwave waveforms with desired parameters can be generated for radar and other applications. In particular, the generation of continuous-wave or pulsed, linearly chirped, and frequency-hopping microwave waveforms with reconfigurable parameters are experimentally demonstrated. In addition, a high-resolution distance measurement experiment is performed to verify the feasibility of applying the proposed microwave waveform generator to radar applications.