Innovative Radar System Concepts and Architectures

The goal of this SBIR project is the development of a fiber-coupled diagnostic system for the comprehensive Tx/Rx-mode calibration and performance-monitoring of large-scale phased antenna arrays. In the proposed calibration system, innovative electro-optic (EO) field sensors will monitor near-field amplitude and phase emanating from the array under observation during Tx-mode calibration, while compact, optically-activated RF emitters will provide reference incident fields to the array for the receive-mode calibration. Both EO sensor and RF emitter will be completely fiber-coupled and do not require any electrical connection. The pure optical signal from the EO sensors/RF emitters will be immune from electromagnetic interference, and the EO sensors/RF emitters can be very flexibly arranged and safely positioned within close proximity to the aperture of the antenna elements. The exceptional flexibility of the optical fiber, onto whose ends the very small EO sensors/RF emitters are attached, makes the proposed calibration approach a viable solution for the characterization of collapsible/deployable arrays, as well as other conventional arrays. The fiber-coupled array calibration system will open a new paradigm of array operation and maintenance, from accurate on-site calibration and real-time detection of malfunctioning cells, to the evaluation of the overall array operating condition.