Angle estimation with a multi-arm spiral antenna

This paper presents an analysis of angle estimation using a single aperture multi-mode spiral. Simple, closed-form expressions for the modal outputs of the multi-mode spiral are derived and used in the angle estimation analysis. It is demonstrated that in addition to the classical phase comparison method, modern super resolution techniques such as MUSIC and MLM can be applied to multi-mode antenna technology for angle estimation. It is further demonstrated that MUSIC and MLM algorithms can be adapted to work in the presence of jamming. Simulated results show that these new approaches give lower bias and variance and also extend coverage toward boresight compared to the traditional comparison method