Application of Frequency-Scanned Bull's-Eye Leaky-Wave for Conical Direction Finding

We demonstrate the application of a 2-D Bull's-Eye (BE) leaky-wave antenna (LWA) for conical direction finding using the frequency scanning mechanism. In contrast to other 2-D LWAs of uniform or quasi-uniform nature, such as Fabry-Perot Antennas (FPAs), the BE-LWA has a periodic nature and therefore its radiation mechanism is based on a higher-order space harmonic. As a result, both the backward-scanning and forward-scanning bands can be used to increase the direction finding performance. This is demonstrated with theoretical results using a printed-circuit BE LWA operating in the frequency band from 14 GHz to 32 GHz.