Distributed Antenna for Counter UAS

We consider the technical feasibility of a wirelessly distributed antenna array for C-UAS using directional microwave frequency energy. Importantly, the large possible size of the distributed antenna permits engagement of UASs and UAS swarms within the near-field region, enabling highly localized effects, ~5 m at a range of 1 km when operating at 1 GHz. In addition to near-field operation, combining N coherent emitters gives an N2 enhancement of irradiance over that of a single emitter, enabling extension of system range by a factor N or a reduction in total system power requirement of N−1 to achieve an equivalent effect. Systems operating at 1 GHz require precise synchronization of the order of 100 picoseconds to ensure a high degree (>90%) of coherence at target and therefore would require semiconductor power amplifiers rather than vacuum electron devices which are typically used as high-power microwave sources. The authors develop a mathematical model implemented in software to explore the potential performance of a wirelessly distributed antenna for C-UAS and suggest some approaches for realization of such a technology.