High Power Compact Mechanically-Phased Helix Array

Diversified Technologies, Inc. proposes to develop a novel high power, high gain, mechanically-phased array antenna comprised of helical elements. This antenna array is designed to operate over the X-band frequency range (8-12 GHz), at Gigawatt peak power levels for High Power Microwave (HPM) weapon systems. The array combines the fast slewing ability of a conformal phased array with the mechanically-phased high power handling capability of a waveguide-fed antenna providing a high performance and compact solution for an HPM antenna. The helical antenna elements feature a wide bandwidth, high gain and circular polarization, which couples well to a wide variety of targets. In this type of antenna, the outputs from the elements add together to form a beam, with the direction of the beam being determined by the phasing of the elements relative to each other. Phasing is accomplished by rotating the circularly polarized elements via a simple and robust drive system that can provide 360 degrees of continuous phase adjustment. This provides sufficient phase adjustment to allow the beam to be steered +/- 20 degrees or more in both azimuth and elevation from boresight. The phased array architecture of this antenna provides a flexible form factor that can be adapted to a wide variety of spaces allowing for easy integration into many platforms.  In the Phase I effort, DTI will design the full mechanically-phased array antenna, design fabricate and test an 8 x 1 element linear array to verify the mechanical phasing, antenna power feed characteristics, and characterize the antenna beam including advanced beamforming (multibeam, multi-targeting) modes. DTI will perform electromagnetic simulations to verify the RF performance of the antenna elements to achieve 30 dBi of gain with low side lobes. Multiple sidelobe reduction techniques such as helical element optimization, amplitude tapering across the elements, element position dithering, and a quarter-wavelength choke around the array perimeter will be utilized.