Advanced Multi-Band Electronic Surveillance Measure (ESM) Antenna

The objective of the Phase 1 and 2 SBIR Program, Topic N04-263, "Advanced Multi-Band Electronic Surveillance Measure (ESM) Antenna," is to develop a multi-band, lightweight ESM antenna, includes communications intelligence (COMINT), electronic intelligence (ELINT) and communications systems and data links, and is capable of being installed on multiple, unmanned air vehicle (UAV) platforms. The antenna may be installed at multiple locations on the air vehicle, such that they can be coherently processed to create an interferometer to measure angle of arrival of emitters. Revolutionary antenna technologies are sought that will be lightweight, provide a wide area RF coverage, and be capable of interfacing with existing and planned UAV ECM/Electronic Intelligence (ELINT) systems. The real challenge is to preserve the gain and coverage characteristics of multiple antennas in a single integrated package. It has been suggested that the full frequency coverage desired is 100 MHz to 18 GHz with an objective of 20 MHz to 40 GHz. Further it would be desirable to be able to transmit over the 20 MHz to 2 GHz frequency range. The system should have a higher gain as the angle of reception approaches the horizon, a 1/R² space loss function. The antenna shall be circularly polarized, thus being able to operate with vertically and horizontally polarized signals also. A single connector shall be used for the full frequency coverage. The VSWR shall not exceed 2:1 over the required frequency band. The primary requirements driven by use on UAV's are: form factor, (shape, size, depth), weight, aerodynamic drag, cost, structural capabilities, and RF performance.