A 300 THz tabletop radar range system with sub-micron distance accuracy

We are presenting a compact radar range system with a scale factor of 10⁵. Replacing the radio frequency (RF) by optical wavelength (300 THz), the system easily fit on a tabletop. We used interferometric time-of-flight to reproduce radar ranging measurements. Sub-micron range accuracy was achieved with a 100 fs laser pulse, which correspond to 3 cm for a s-band (3 GHz) radar. We demonstrated the system potential on a simple target, and compared the results with radio frequency measurement using a vector network analyzer. We also present measurement with a more realistic model, a 3D printed reproduction of the USS Arizona battleship, for which a 3D model is extracted from the ranging data. Together with our previous demonstration of radar cross section measurement with a similar system, this report further validates our proposal to use optics to simulate radar properties of complex radio frequency systems.