The Logarithmically-non-uniform Helix Antenna Mounted Above a Finite Ground Plane


  • Ike Mowete University of Lagos, Akoka, Lagos, Nigeria
  • Ayotunde Ayorinde University of Lagos, Akoka, Lagos, Nigeria
  • Adeniyi Adehola Federal University, Otuoke, Bayelsa State, Nigeria



In this paper the influence of ground plane size on the performance characteristics of a thin-wire helical antenna characterized by a logarithmically varying turns spacing, and mounted above a circular ground plane of finite extent, is systematically investigated. The moment-method formulation utilized in the paper involves a wire-grid model for the ground plane as well as explicit expressions, deriving from a vector potential approach, for the radiation fields of this ‘loghelix’. Subsequent computational results obtained for a candidate 8-turn ‘loghelix’ axial-mode ˀantenna using various combinations of ‘logarithmic variation factor’ and ground plane size, very clearly reveal that limiting the size of the ground plane to finite dimensions significantly improves antenna performance. Maximum gain obtainable, for example, emerged as 16.45dBi when a finite ground plane is utilized, as against 13.55dBi for the corresponding antenna, backed by an infinite ground plane. The associated axial ratio performance is characterized by blobid1.jpg for the finite ground case, and blobid2.jpg , for the infinite ground plane case. A notable finding of the investigations is that the dip that typically features in the power gain profiles of antenna structures backed by finite ground planes will be eliminated, when ground plane size, relative to antenna size exceeds a certain minimum.

Author Biography

Ike Mowete, University of Lagos, Akoka, Lagos, Nigeria

Ike Mowete is a Professor of Engineering Elecromagnetics at the University of Lagos, where he has been teaching since 1984. His research interests include antennas and radiowave propagation, electromagnetic compstibility, and numerical methods for the solution of field problems




How to Cite

Mowete, I., Ayorinde, A., & Adehola, A. (2022). The Logarithmically-non-uniform Helix Antenna Mounted Above a Finite Ground Plane. ELEKTRIKA- Journal of Electrical Engineering, 21(1), 25–34.