Towards Software-Defined Optical Sensing

Abstract

Modern optical sensors are increasingly limited by hardware-defined architectures that constrain flexibility and demand escalating complexity to achieve robustness, stability, and precision. My research explores Digital Interferometry, a software-encoding method to multiplex interferometry with the aim of transferring hardware complexity to reconfigurable digital signal processing. We are effectively making it the “software defined radio” of interferometry. Digital Interferometry was first developed for the LISA gravitational wave mission, with the original paper by Shaddock published in 2007. The method works by encoding optical fields with unique ‘digital’ signatures. These can be uniquely identified, allowing multiple interferometric measurements to be isolated, synthesised, and parallelised from a single detector. In the years since initial publication, the technique has been incubated at the Australian National University, developing methods for wavelength, polarisation, temporal and spatial multiplexing. In this talk, I will introduce Digital Interferometry as a toolkit for realising software defined optical sensing and highlight some of the group's recent work across several domains including signal isolation, molecular dispersion spectroscopy, optical gyroscopes and optical phased arrays. The presentation will conclude with a discussion of ongoing projects and longer-term prospects for multi-modal sensing combining radio-frequency and optical domain measurement, and research towards non-hierarchical sensor networks and control.