Optically Based Instantaneous microWAve iMagery – OBIWAM

OBIWAM is a collaborative research-enterprise (PRCE) project composed by three industrial partners and two academic ones, which is voluntarily focused on applications.
It aims to design and experimentally demonstrate a real-time-high-resolution microwave imagery system for security applications (body scanners, vision through walls, target detection in opaque environments, non-destructive testing of luggage) using microwave frequencies and photonic and optoelectronic devices. The proposed system relies on a new technique that consists in measuring a single signal by performing an analog coding of the signals received by an antenna network on a single output channel guaranteeing a simplified architecture requiring only a single Analog-to-Digital Converter. The signals collected at each antenna will be optically processed (delays management) and then concentrated to the single output channel by means of a microwave photonics summation. The electro-optical conversion will be carried out using Silicon Photonic modulators, a technology that has a bright future and will ensure the compactness and the low cost of the system. Thanks to a judicious choice of optical delays, the waveforms received by each antenna will be reconstructed in post-processing by applying SIMO or MIMO imaging algorithms. So, for OBIWAM there is a need to include innovative components such as silicon modulators and microwave photonics summation devices, one of the key elements of the system, and new digital signal processing.
The aim of the partners is to provide at the end of the project an innovative microwave photonics realtime demonstrator with single-shot/single-channel acquisition and for the detection of targets. It will aim to show the potential offered by an innovative approach and to extrapolate the studies, through simulation, to a system with better image resolution. The development of a system simulation platform that includes both component models and signal processing is thus another challenge of OBIWAM.