In this STTR phase I, HYPRES and University of California Riverside will demonstrate the feasibility of a three-dimensional electromagnetic (EM) sensor for accurate vector sensing and geo-location of complex RF emitters exploiting the novel quantum electrodynamic properties stemming from innovations in superconducting nanoelectronics specifically in utilizing direct-write, high temperature superconducting (HTS) nano-Josephson junction (nano-JJ) SQUID sensors configured using our patented anti-gradiometer technique. The SQUID technology is based on direct-write technique using helium focused helium ion beam (FHB). We will develop analytical solutions for a three-dimensional EM sensor that exhibit quantum properties. We will incorporate these properties into direction finding (DF) and geo location energy vector formulations for an enhanced representation of an RF signal with respect to time accuracy. We will design a three-dimensional quantum-based EM sensor with accompanying complex EM vector signal formulations using our patent-pending Anti-gradiometer DF approach.We will develop and apply a powerful 3D program to simulate DF circuits based on nano-JJ technology enabled by HTS SQUIDs made with FHD process. Designs will be simulated, designed and evaluated. The project will lead to the development of high-sensitivity instrumentation with superior performance, small cost, weight, size and power with high commercial potential.