An active electronically scanned array antenna demonstrator with a novel RF feeding network concept

The objective of this work is the development of an Active Electronically Scanned Array (AESA) antenna demonstrator for civil maritime radar. AESA technology has been applied in a wide range of fields; however, it has been restricted to high-end and military markets, mostly because of its high overall costs. This research aims to fulfil regulatory requirements of civil maritime radar at reduced cost. An AESA antenna whose single active antenna element supports mixed signal operation (analogue and digital) allows to solve the additional challenges imposed by this regulation. Moreover, an innovative RF feeding network operation and a plain antenna aperture concept are proposed. The array can be produced with an inexpensive extrusion process, resembling existing navigation radar antennas. The RF feeding network lacks any isolation between its ports. The similarity between simulated beam-forming and the measured patterns show that ideal performance is almost achieved. In addition, the pattern sensitivity to interferences is analysed, and inexpensive protection solutions are proposed. In summary, this work shows how phased-array technology can be open to further fields of applications.