Interleaved Parasitic Arrays Antenna (IPAA) for Active VSWR Mitigation in Large Phased Array Antennas With Wide-Angle Scanning Capacities

International audienceThis paper explores a new concept for the design of high scanning-range phased array antennas: the Interleaved Parasitic Arrays Antenna or IPAA. In this concept, we use periodic parasitic elements and the generator impedance to control the Active Voltage Standing Wave Ratio (AVSWR) over a wide scanning range. This new array architecture comes with a design methodology enabling a smooth stepby-step design process aiming at reducing the need for full-wave calculations. First, a numerical dualpolarization design is presented in detail to illustrate the methodology and to give the design keys to the reader. Then, a prototype working in the 5G C-band between 3.4 and 3.8 GHz (11% bandwidth) was designed using this methodology and measured for a 36-element array. It is meant to demonstrate and validate the mutual coupling management done by the interleaved parasitic arrays and the design process accuracy. Good correspondence between measurements and simulation was found and the proposed unit cell with its corresponding tile can be integrated in a larger phased array with active modules to perform beam steering over an important scanning range without deteriorating the AVSWR. The proposed unit cell is designed for a high-scanning range going from θ = 0 • to θ = 70 • for every ϕ-directions and shows an active reflection coefficient for an infinite array below −13.6dB. INDEX TERMS 5G, active antenna arrays, active voltage standing wave ratio (AVSWR), antenna arrays, beam steering, C-band, impedance matching, mutual couplings, parasitic elements, periodic structures, superstrate