Conformal, Ultra-Light Interlaced Active Electronically Steerable Antenna (UL-AESA) for Unmanned Aerial Vehicle (UAV) Radar and COMINT(2007026)

Hittite proposes to develop a small, light-weight, interlaced AESA to provide ground surveillance radar and COMINT capability from a small UAV. The development will focus initially on the Ka-band radar antenna. This thin (e.g., 85 mil), 256-element (8 x 32) 35 GHz radar array will conform to and be structurally integrated with a 1.35” x 5.4” x 0.06” section of the bottom of the fuselage. The array itself will weigh about 0.17 # and consume 36 W. Including power conditioning increases the weight to 0.4# and the power consumption to 43 W. The array will radiate 9 W average power and provide a sensitivity of 21 dB. Beams will scan at least +- 60o will sufficient agility to compensate for UAV maneuvers. The L-/S-band COMINT antenna will span 1 – 4 GHz, although only a small portion of the band will be observed at any one time. The notional 64-element array will measure 7.4” x 20.7” x 0.06” and consume less than 40 W. Its 4:1 frequency range requires evolving, wideband radiator techniques to minimize its weight. If the technology proposed for the Ka-band antenna applies to the L-/S-band antenna, then it will weigh about 4#. The active T/R circuitry will be realized in MHEMT technology for low noise figure and high PA efficiency and low power dissipation. Digital beam former circuits will be built in SiGe BiCMOS technology at IBM through DoD’s ITAR-compliant, Trusted Foundry (TF) agreement. Digital Sub-Arrays (DSAs) realized with wafer-scale antenna (WSA) technology will contain all the site-specific electronics for 64 radiating elements plus data conversion and digital beam forming. True-time delay beam forming will minimize squint. The Phase I effort will focus on a Ka-band AESA. The feasibility of realizing the AESA within the size, weight, and power (SWaP) constraints of a small UAV will be assessed. Critical circuitry will be developed during Phase II prior to fielding a complete antenna in Phase III. Interleaving the L-/S-band antenna will be considered separately.