Millimeter-Wave Array Antenna Architectures Employing Joint Power Combining and Beam Steering for Next-Generation Backhaul Applications

We investigate the capabilities and limitations of joint power-combining and beam-steering techniques for millimeter-wave antenna applications. In this analysis, both functionalities are realized simultaneously through a power-combining and beamforming (PC-BF) network interconnecting an input array of active channels with an array of antenna elements. The first part of the paper provides a review of state-of-the-art hardware architectures of such PC-BF networks and examines their suitability for millimeter-wave applications. The architectures are grouped into two classes depending on the array embedded element patterns properties. Next, a unified PC-BF network is proposed where both functionalities are implemented in a single millimeter-wave waveguiding block. A full-wave model of such a network with 6 inputs and 7 outputs is investigated, with its application demonstrated for a W-band focal-plane array feeding a backhaul reflector antenna.