New Reference Function for Post-Processing Uncertainty Evaluation in SAR Compliance Tests

A reference function for the post-processing uncertainty evaluation in specific absorption rate (SAR) compliance tests is proposed. The new reference function, derived from real SAR distributions measured during compliance sessions of handsets, is characterised by a double Gaussian distribution with asymmetrical standard deviation parameters, in each half space. Standard deviation parameters as well as SAR penetration are frequency dependent data. The proposed reference function also takes into account SAR distributions with two (or more) local maxima. The analysis for the derivation of the reference function parameters based on GSM900, DCS1800, UMTS and IEEE 802.11b measured SAR distributions is presented as well as details on uncertainty computations. A generalization of the method is presented too.