Technical References

The use of microwave modelling is increasing. Microwave sensing of the permittivity of materials is increasingly used for indirect assessments of a wide range of properties, moisture content being the foremost but mechanical strength, shelf life and other quality factors also being assessed.
There is a need for improved permittivity data of reference liquids and solid reference materials both in modelling and sensor evaluation. Our contributions to fulfilling this need is by developing new measurement applicators (such as the two shown to the left on the homepage), and by using these and other systems, in co-operation with SIK – The Swedish Institute for Food and Biotechnology, for accurate measurements.

It is intended to maintain and expand  "best data" on a number of suitable reference substances on this website.

As to the choice of reference liquids other than water, several criteria have to be observed. Equations for the forward and reverse Debye and Cole-Cole equations, a discussion of these criteria and a list is given
here (400 kB, updated 2006 June 02)

Three presentations were made at the
ISEMA (International Society for Electromagnetic Aquametry) conference May–June, 2005. Work has continued and  updated data are given in the file below (updated 2006–05–25).

DATA OF LIQUID WATER FROM –20°C TO +100 °C (140 kB, updated 2006 May 25)    


In June 2006 I decided to provide 2450 MHz permittivity data as function of enthalpy, for meat and bread, including the phase transition (thawing). Such data are indispensable for microwave modelling of actual processes with these foods. Please contact me if explanations are needed.

This page with subpages describes the basic microwave interaction mechanisms and properties of substances in English  

Denna sida och följdsidor beskriver de grundläggande verkansmekanismerna hos mikrovågor och materialegenskaper på svenska