On the Study of the Near-Fields of Electric and Magnetic Small Antennas in Lossy Media

In this communication, the near-field radiation characteristics of electric and magnetic antennas when surrounded by a lossy dielectric medium are described. This study is relevant for cases such as implanted antennas, submarine or underground communications where the antenna's near field consists of lossy dielectric media such as human tissues, minerals or saline water. Theoretical results for both types of small antennas are presented and expressions to show the differences in stored energy and radiated power in the radian sphere around the antenna are formulated. It is found that magnetic antennas give much better performance when surrounded by a lossy dielectric..

[1]  H.A. Wheeler,et al.  Fundamental Limitations of Small Antennas , 1947, Proceedings of the IRE.

[2]  L. J. Chu Physical Limitations of Omni‐Directional Antennas , 1948 .

[3]  James R. Wait,et al.  The Magnetic Dipole Antenna Immersed in a Conducting Medium , 1952, Proceedings of the IRE.

[4]  H. Wheeler,et al.  Fundamental limitaions of a small VLF antenna for submarines , 1958 .

[5]  Roger F. Harrington,et al.  Effect of antenna size on gain, bandwidth, and efficiency , 1960 .

[6]  R. Collin,et al.  Evaluation of antenna Q , 1964 .

[7]  L. Ball,et al.  Radio Transmission to and from Underground Coal Mines - Theory and Measurement , 1973, IEEE Transactions on Communications.

[8]  김기채 Small Antennas , 1992, Antenna and EM Modeling with MATLAB® Antenna Toolbox.

[9]  Thomas G. Zimmerman,et al.  : Near-field , 2022 .

[10]  C. Gabriel Compilation of the Dielectric Properties of Body Tissues at RF and Microwave Frequencies. , 1996 .

[11]  J. Mclean A re-examination of the fundamental limits on the radiation Q of electrically small antennas , 1996 .

[12]  A. Karlsson,et al.  Physical limitations of antennas in a lossy medium , 2004, IEEE Transactions on Antennas and Propagation.

[13]  Y. Rahmat-Samii,et al.  Implanted antennas inside a human body: simulations, designs, and characterizations , 2004, IEEE Transactions on Microwave Theory and Techniques.

[14]  P. S. Hall,et al.  Antennas and propagation for body centric communications , 2006, 2006 First European Conference on Antennas and Propagation.

[15]  S. A Re-Examination of the Fundamental Limits on the Radiation Q of Electrically Small Antennas , 2008 .

[16]  Jianming Jin Theory and Computation of Electromagnetic Fields , 2010 .

[17]  W. Stutzman,et al.  Fundamental limits on antenna size: a new limit , 2011 .

[18]  K. Sarabandi,et al.  Low Profile, Miniaturized, Inductively Coupled Capacitively Loaded Monopole Antenna , 2012, IEEE Transactions on Antennas and Propagation.

[19]  Safieddin Safavi-Naeini,et al.  Maximum Gain of a Lossy Antenna , 2012, IEEE Transactions on Antennas and Propagation.

[20]  Majid Manteghi,et al.  Electrically coupled loop antenna as a dual for the planar inverted‐f antenna , 2013 .

[21]  M. Manteghi,et al.  Performance of an Implanted Electrically Coupled Loop Antenna inside Human Body , 2014 .