A comprehensive study of monofilar helices for remote operations

The helical beam antenna, invented by John D. Kraus in 1946, possesses inherent properties, such as desirable radiation pattern, impedance and polarization characteristics, over a relatively wide frequency range. It is characterized by two modes, namely, normal-mode and axial-mode; the paper discusses the axial-mode at some length, due to its suitability in space applications. Array formation is also mentioned.