Nearfield / Farfield Calculator
Perhaps the first thing to know, is the location of the absorber with respect to the antenna or emitter. Is it in the near field or far field? The definition for this is well documented in the literature; but it basically deals with whether the emanating wave front is sufficiently far from the source to be flat enough to conform with the planar math equations.

ARC have included a calculator in the tool box to assist in this determination. The information that you will need is the frequency of interest and the principle dimension of the antenna.

 

 

 

 

 

 

 

 

 

Input:

 

Input:

 

Output:

 

Output:

 

Frequency (GHz)

 

D Max (In.)

 

Far Field (In.)

 

Far Field (Ft.)

 

 

 

 

 

 

 

 

 

 

=

 

 
Automatic Recalculation         




Wavelength/Frequency Calculator

A second vital bit of information is the wavelength at the frequency of interest. This is easy enough to calculate for air (free space), but is reduced in higher dielectric matter. Both of these numbers can be obtained from another calculator in the toolbox. The information that you need is the frequency and the dielectric of the medium or material.

We hope that these tools are helpful in guiding you in the selection of the correct absorber for your application.
Calculating Quarter Wave Thickness in a Dielectric
Frequency of Interest: GHz
Dielectric Constant:
Wavelength in Air: inches
Wavelength in Dielectric: inches
Dielectric Quarter Wave Thickness: inches
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19-21 Finch Drive
Braintree, Essex.
CM7 2SF, UK.
Tel: +44 (0)1376 348115
Fax: +44 (0)1376 345885

 

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