Transmit-Receive Extremely Low Frequency to Very Low Frequency Directional Antenna System

To address the DARPA need for a small low electromagnetic frequency directional antenna, Physical Optics Corporation (POC) proposes to develop a new Transmit-Receive extremely low frequency– very low frequency (ELF-VLF) Directional Antenna (TREDA). This proposed device is based on a compact resonant two-way antenna and an atmospheric plasma waveguide. The use of a highly directional waveguide will enable the TREDA system to provide directionality of over 50 dBi with single-frequency operation at frequencies from 1 Hz - 100 kHz resulting in a narrow beamwidth of 0.1 m on the ground at 100 m standoff. The system’s resonant antenna provide transmit and receive capability in the ELF-VLF bands in a compact (~0.5 m in any direction) device. As a result, the TREDA system directly meets DARPA needs for a low-frequency antenna system for detection (and also generation) of telluric currents to detect potential threats concealed in underground tunnels and facilities from airborne platforms. In Phase I, POC will demonstrate the feasibility of TREDA by assembling and testing a proof-of-concept prototype of the TREDA system. In Phase II, POC plans to develop a fully functional prototype and test plan, and will demonstrate functionality of the TREDA system to DARPA personnel.