Design of a TEM-Cell with Increased Usable Test Area

Kresimir MALARIC; Juraj BARTOLIC

Article Details

Design of a TEM-Cell with Increased Usable Test Area

Authors:

Kresimir MALARIC | Juraj BARTOLIC

Publisher:

TUBITAK

Journal:

Turkish Journal of Electrical Engineering and Computer Science 2003 Vol.11 Issue 2, pp.143-154

Document Type:

Article

Publication Date:

1/2003

Document Language:

Turkish

Document ID (Org No.):

2000744288

Frequency:

Bimonthly

eISSN:

1303-6203

pISSN:

1300-0632

Abstract:

 

Transversal electromagnetic mode cells (TEM-cells) are used  for electromagnetic compatibility measurements (emission and  immunity), and for biomedical applications.  Over the years, higher  and higher frequencies are being used, which demands smaller  transmission structures in order to obtain the homogeneous field  distribution due to resonance.  Such resonance destroys the TEM field,  introducing higher order modes.  The goal was to design the TEM-cell  for GSM frequencies that will have a larger area with a homogeneous  field used for testing, while still obtaining the characteristic  impedance.  Commercial TEM-cells used for frequencies of 900 MHz have  only 2 cm in height available for testing, while the proposed TEM-cell  has 5 cm in vertical dimension suitable for EMC testing.  The problems  regarding characteristic impedance, resonance, higher order modes,  dimensions and usable test area are discussed.  Numerical modeling  with the Quickfield", which uses finite element method (FEM), and  MAFIA", which uses finite integration technique (FIT) gave the  electromagnetic field distribution and calculation of the higher order  modes.  The measurements of VSWR and insertion loss showed good  correlation with the model.  At 935 MHz, the VSWR is 1.1 which makes  the cell applicable for GSM frequencies.  The higher order modes  appear at 490 MHz and 740 MHz, but another frequency area is usable.   The TEM-cell has a characteristic impedance of 75 W and an  increased usable test area.  It can be utilized for EMC measurements  and biomedical applications from DC to 1 GHz.

 

Transversal electromagnetic mode cells (TEM-cells) are used  for electromagnetic compatibility measurements (emission and  immunity), and for biomedical applications.  Over the years, higher  and higher frequencies are being used, which demands smaller  transmission structures in order to obtain the homogeneous field  distribution due to resonance.  Such resonance destroys the TEM field,  introducing higher order modes.  The goal was to design the TEM-cell  for GSM frequencies that will have a larger area with a homogeneous  field used for testing, while still obtaining the characteristic  impedance.  Commercial TEM-cells used for frequencies of 900 MHz have  only 2 cm in height available for testing, while the proposed TEM-cell  has 5 cm in vertical dimension suitable for EMC testing.  The problems  regarding characteristic impedance, resonance, higher order modes,  dimensions and usable test area are discussed.  Numerical modeling  with the Quickfield", which uses finite element method (FEM), and  MAFIA", which uses finite integration technique (FIT) gave the  electromagnetic field distribution and calculation of the higher order  modes.  The measurements of VSWR and insertion loss showed good  correlation with the model.  At 935 MHz, the VSWR is 1.1 which makes  the cell applicable for GSM frequencies.  The higher order modes  appear at 490 MHz and 740 MHz, but another frequency area is usable.   The TEM-cell has a characteristic impedance of 75 W and an  increased usable test area.  It can be utilized for EMC measurements  and biomedical applications from DC to 1 GHz.

Article Details

Design of a TEM-Cell with Increased Usable Test Area

Authors: Kresimir MALARIC | Juraj BARTOLIC

Publisher: TUBITAK

Journal: Turkish Journal of Electrical Engineering and Computer Science 2003 Vol.11 Issue 2, pp.143-154

Document Type: Article

Publication Date: 1/2003

Document Language: Turkish

Document ID (Org No.): 2000744288

Frequency: Bimonthly

eISSN: 1303-6203

pISSN: 1300-0632

Issues

Authors:

Kresimir MALARIC | Juraj BARTOLIC

Publisher:

TUBITAK

Journal:

Turkish Journal of Electrical Engineering and Computer Science 2003 Vol.11 Issue 2, pp.143-154

Document Type:

Article

Publication Date:

1/2003

Document Language:

Turkish

Document ID (Org No.):

2000744288

Frequency:

Bimonthly

eISSN:

1303-6203

pISSN:

1300-0632