Photonics-based receiver for decoupled velocity and range measurement

Photonics-based receiver for decoupled velocity and range measurement is proposed and demonstrated. A dual-chirp LFM signal is used. At the receiver, the reference signal and the received echoes are modulated to the optical carrier, respectively. By introducing the microwave photonic image reject mixing, the frequency components corresponding to the target range and velocity can be obtained simultaneously. No complex simulation source in electrical digital domain is needed, and no special requirement with the dual-chirp LFM signals is required. A proof-of-concept experiment is taken. A dual-chirp LFM signal centered at 10 GHz with a 4-GHz bandwidth is used. The target range and the Doppler-frequency shift are successfully obtained.