Investigation of the mutual coupling between antennas located in the near field of each other



This research project is carried out in corporation with NOKIA in a ph.d. study by Jesper Thaysen supervised by Kaj B. Jakobsen, Hans Erik Gram and Jens Troelsen, the two latter being from NOKIA

  • Jesper Thaysen (Ph.d. student)
  • Kaj B. Jakobsen (Associate professor)
  • Hans Erik Gram (Antenna engineer, NOKIA)
  • Jens Troelsen (Antenna engineer, NOKIA)


Nokia Denmark A/S funds the Ph.D. study


Theoretical, numerical and experimental investigations of the near field of an antenna having an object, e.g., another antenna, located in the near field. Especially, the correlation, the coupling between and the current distribution on the metallic surface of the antennas will be investigated. The main goal of the project is in particular to investigate the near field coupling between two or more antennas, having the same or different resonant frequency.

Commercial available electromagnetic simulation program based on the methods of moment program as well as program based on finite difference time domain principle will be used. Also analytically expressions implemented in computer software will be used. 

The presented antenna configuration consists of two different PIFA's with a similar long and thin shape. They are located on a 40 ´ 100 mm2 ground plane. PIFA 1 is 36 mm long, 1.2 mm wide and 7.5 mm high. The feed point is located 3.3 mm from the edge where a 90-degree bend forms the short to the ground plane. PIFA 2 is oriented parallel to PIFA 1 and is 35 mm long, 0.9 mm wide, and the feed point is located 1 mm from the shorting pin. The separation between the PIFA's is 2.5 mm.

The measured field distribution shown in Figure 1 contains the electrical field amplitude at 2.5 mm above the radiating element. In all four sub-figures the highest field intensity is attributed to the region where the PIFA elements are located, i.e. in the lower part of the figures. A roll-off in the intensity towards the edges of the figures are observed.


  • Thaysen, J., Jakobsen, K. B., MIMO channel capacity versus mutual coupling in multi element antenna system, Accepted for AMTA 2004. Thaysen, J., Jakobsen, K. B., Small inductor Loaded mobile phone Antenna, Accepted for JINA 2004 Thaysen, J., Jakobsen, K. B., Capacitive loaded mobile phone Antenna, Accepted for JINA 2004
  • Thaysen, J., Jakobsen, K. B., Coupling reduction by lumped components, Accepted for JINA 2004
  • Thaysen, J., Jakobsen, K. B., Stub Loaded Low profile loop patch Antenna on a Finite Ground Plane, Proceedings of 2004 URSI International Symposium on Electromagnetic Theory, Pisa, Italy, 2004.
  • Thaysen, J., Jakobsen, K. B., Near field Distribution from a Planar Inverted-F Antenna, Proceedings of Twelfth International Conference on Antennas & Propagation, Univ. of Exeter, UK, pp 4, 2003.
  • Thaysen, J., Mutual Coupling Between Two Identical Planar Inverted-F Antennas, Proceedings of IEEE Antennas and Propagation Society International Symposium, pp 504-507, 2002 Digest, Volume 4, 2002.
  • Thaysen, J., Jakobsen, K. B., Miller, E., Modeling of a Frequency Independent Antenna, Proceedings of USNC/URSI National Radio Science Meeting, pp 1, 2002.


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