Energy Efficient HF Transmit Antennas

In this N12A-T015 Phase I effort, the team of Pharad and UCLA (University of California, Los Angeles) propose to develop a highly efficient High Frequency (HF) transmit antenna based on utilizing existing structures that are available in the surrounding environment, as radiation mechanisms. We propose to create antennas on existing structures or other parts of the platform using either of two strategies: (i) by developing efficient antenna"exciters"that can efficiently couple power to existing metallic structures (such as fences, roofs, posts and drain-pipes or even vehicles, hull plates and armor); and (ii) by incorporating conductive paints that can be applied to walls and other non-metallic structures. By utilizing these techniques we believe we can resolve the fundamental issue of developing an efficient HF antenna that is not unwieldy and can be readily transported. We also plan to investigate how to interconnect these potential HF radiators using sparse array concepts to further enhance the overall efficiency. Throughout Phase I we will undertake experimental investigations when appropriate. The Phase I design activities will lay the foundations for the proposed Phase II effort, the focus of which will be to develop a proof-of-concept version of our proposed efficient HF transmit antenna system.