IEEE Draft Recommended Practice for Determining the Peak Spatial-Average Specific Absorption Rate (SAR) in the Human Head from Wireless Communications Devices: Measurement Techniques

IEEE Std 1528-200X specifies protocols and test procedures for the measurement ofthe peak spatial-average SAR induced inside a simplified model of the head of users of certainhandheld radio transceivers. These transceivers are intended to be used for personal wirelesscommunications services, operate in the 300 MHz to 6 GHz frequency range, and are intended tobe operated while held against the ear. The results obtained by following the protocols specifiedin this recommended practice represent a conservative estimate of the peak spatial-average SARinduced in the head of a significant majority of persons, subject to measurement and otheruncertainties that are defined in this standard. The results are representative of those expectedduring conditions of intended use of a handheld wireless device. It is not the intent of thisrecommended practice to provide a result representative of the absolute maximum SAR valuepossible under every conceivable combination of head size, head shape, handset orientation, andspacing relative to the head. The measurement of SAR induced in the external tissues of thehead, e.g., the external ear (pinna), is not addressed in this standard. This standard also does notaddress the body SAR measurements typically required for wireless handsets. The followingitems are described in detail: measurement concepts, measurement techniques, instruments,calibration techniques, simulated-tissue (phantom) models, including homogeneous anatomically-equivalent models of the human head and simple phantoms for validation of the SARmeasurement system, and the limitations of these systems when used for measuring the spatialpeakmass-averaged SAR. Procedures for calibrating electric field (E-field) probes used for SARmeasurements and assessing the SAR measurement and system uncertainties are provided inthe annexes. This recommended practice is intended primarily for use by engineers and otherspecialists who are familiar with electromagnetic (EM) theory and SAR measurement techniques.This standard does not recommend specific SAR limit values since these are found in otherdocuments. The benefits to the users include standardized and accepted protocols, validationtechniques, and means for estimating the overall measurement uncertainty in order to producevalid and repeatable data.