Antenna diagnostics for power flow in extreme near-field of a standard gain horn

Paula Irina Popa, Olav Breinbjerg

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review


The plane wave spectrum of an aperture antenna can be calculated from a complex measurement of the radiated near- or far-field and it facilitates antenna diagnostics for the extreme near-field of the antenna. While antenna diagnostics often concerns the magnitude of the co-polar field, the plane wave spectrum actually allows for determination of both magnitude and phase of all three components of the electric as well as the magnetic field - and thus also the Poynting vector. In this work we focus on the Poynting vector and thus the power flow in the extreme near-field; as an example we employ a 60 GHz standard gain horn. Measurements obtained with a planar near-field antenna measurement set-up reveal that the power flow has not only a normal component - but also tangential components - in the aperture and, furthermore, that these components possess oscillations along the E-plane. We show that these oscillations are not merely a “Gibbs-like” phenomenon due to the availability of only the visible region of the plane wave spectrum and they are not caused by multiple reflections between the horn and the near-field probe - but resulted from the interference between the direct field and the edge-diffracted fields in the horn aperture. An analytical model based on the Geometrical Theory of Diffraction is established, and it is demonstrated that this model qualitatively as well as quantitatively predicts the measurement results for the power flow. A full-wave analysis is carried out and the simulation results show qualitatively the intricate physical mechanism of the power flow distribution.
Original languageEnglish
Title of host publication2016 10th European Conference on Antennas and Propagation (EuCAP)
Number of pages5
Publication date2016
Pages5 pp.
ISBN (Print)978-8-8907-0186-3
Publication statusPublished - 2016
Event10th European Conference on Antennas and Propagation - Davos, Switzerland
Duration: 10 Apr 201615 Apr 2016
Conference number: 10


Conference10th European Conference on Antennas and Propagation


  • Apertures
  • Antenna measurements
  • Analytical models
  • Load flow
  • Magnetic field measurement
  • Interference
  • Magnetic fields
  • millimeter wave measurements
  • antenna diagnostics
  • Single antennas
  • Electromagnetic wave propagation
  • Other radio links and systems
  • aperture antennas
  • electric fields
  • geometrical theory of diffraction
  • load flow
  • magnetic fields
  • near-field communication
  • power flow
  • standard gain horn
  • plane wave spectrum
  • aperture antenna
  • electric field
  • magnetic field
  • Poynting vector
  • planar near-field antenna measurement
  • direct field
  • edge-diffracted fields
  • horn aperture

Cite this

Popa, P. I., & Breinbjerg, O. (2016). Antenna diagnostics for power flow in extreme near-field of a standard gain horn. In 2016 10th European Conference on Antennas and Propagation (EuCAP) (pp. 5 pp.). IEEE.