Recent Advancements on Wideband Phased Array Antennas for High Power Microwave Applications

This paper presents a review of recent advancements in the design and development of wideband phased-array antennas for high-power microwave applications and discusses the challenges involved in accomplishing this important task. Achieving the simultaneous requirements of high-power handling capability, electronic beam scanning, and ultra-wide bandwidths is extremely challenging, if not outright impossible, with current active phased array antennas. Passive phased-array antenna architectures can be a viable solution for meeting these requirements, particularly for high-power microwave (HPM) applications requiring the radiation of pulsed waveforms with extremely high instantaneous power levels (e.g., hundreds of megawatts to gigawatts). We present a brief review of the state-of-the-art in active and passive phased-array antenna technologies. Subsequently, a review of the recent research and development conducted at University of Wisconsin-Madison in developing high-power-capable, ultra-wideband (UWB), electronically reconfigurable lens antennas operating based on the polarization-rotation phase shift concept is presented. The capabilities of this technology as well as challenges in using it to develop gigawatt-class phased-array antennas are presented and discussed. This technology holds great promise in reducing the cost and complexity of development of ultra-wideband HPM phased array antennas for potential use in radar, electronic warfare, directed energy, power beaming, and high-throughput microwave/mm-wave communications applications.