EMF Protection Products
Accurate RF dosimetry measurements in simulated humans are difficult to perform, yet they are essential in establishing the compliance of the phone with the relevant compliance standards. The new harmonized SAR test method adopted by CENELEC and IEEE will ensure that the measurement regimes used to test compliance with either the ICNIRP or IEEE exposure standards are largely the same. The following provides only an outline of the complicated process used in measuring the SAR values.
Essentially the SAR measurement system comprises a phantom human head, specially developed liquids, a robot fitted with a measurement probe, and a mobile phone powered up to its maximum certified power level.
In order to achieve a measure of SAR that will include all types of people, a phantom has been produced that is based upon the dimensions of a large adult male head (it has been shown that a larger head is exposed to a higher SAR) as measured on US Army personnel. This phantom has been constructed with compressed thin ears to simulate users with small ears. In addition – right and left model heads are used to ensure that the different exposure areas caused by the asymmetric location of the antenna in many phones are being measured. Cell Tower Protection
The phantom is filled with a liquid that correlates with the dielectric properties of human head tissue.The dielectric properties of ‘head tissue’ have been calculated taking into account the properties of human brain tissue and the matching effects of the outer tissue layers of the head (e.g., skin and skull) to provide a conservative overestimate of the values. Different ‘recipes’ are used for tests on different frequencies.