Electro-Optically Guided Radar Imaging

Millimeter-wave RADAR imaging holds significant promise for many applications from rotorcraft DVE mitigation to standoff security screening. A key challenge of this imaging modality, however, has been the implementation of an effective method for creating an image without relying on either mechanical scanning or expensive, high SWAP phased array techniques. Herein, we present a concept for creating a phased array RADAR system based on optical excitation and readout of conformal antenna arrays. This work builds heavily on an operational passive millimeter-wave imager designed for rotorcraft DVE mitigation that utilizes optical upconversion to sample a distributed antenna array and a demonstrated distributed transmit array that utilizes photonic techniques for the generation and phasing of millimeter-wave signals across the array. Under the proposed effort, PSI will adapt these technologies to create an all optically addressed conformal RADAR transceiver with capabilities for high speed electronically scanned image formation. Key aspects of this effort will include the development of optical sampling techniques for range binning information and phasing algorithms to maximize information gathering capabilities of the imaging RADAR.