Software Defined Optical Interferometry

The flexibility offered by software-defined hardware (SDH) platforms makes it possible to implement optoelectronic systems which can be readily configured to adapt to multiple high-speed optoelectronic engineering applications. Two software-defined, optical heterodyne interferometers (SDOI) were built using low-cost commercial software-defined radio (SDR) platforms. The first SDOI uses a digital television receiver USB dongle, to measure sub-nanometer periodic displacements in the MHz range. The other SDOI uses a SDR transceiver, to synthesize the optical excitation and to demodulate the heterodyne output signals. It is applied to study sub-microsecond pulsed optoacoustic signals in liquids.