Detail of YD/T 1644.1-2007

Introduction of YD/T 1644.1-2007

1 Scope This part specifies the specific absorption rate (SAR) for transmitting device intended to be used with the radiating part of the device in close proximity to the ear. This applies to any electromagnetic field (EMF) transmitting device with frequency range from 300 MHz to 3 GHz, including mobile phones, cordless phones, etc. The objective of this standard is to specify the measurement method for demonstration of compliance with the specific absorption rate (SAR) limits for such devices. This part is just the standard about electromagnetic radiation measurement method, rather than the standard about safety limit. 2 Normative References The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding correction to), or revisions of, any of these publications do not apply. However, the parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards. For undated references, the latest edition of the normative document referred to applies ISO Guide-1995 Guide to the Expression of Uncertainty in Measurement ISO/IEC 17025-1999 General Requirements for the Competence of Testing and Calibration Laboratories 3 Terms and definitions For the purposes of this part, the following terms and definitions apply. 3.1 attenuation coeffcicent numerical factor intended to account for attenuation due to the human head or body tissue between the source and a specified point 3.2 average (temporal) absorbed power value of the time-averaged rate of energy transfer given by (3-1) Where P(—)avg——the average power in watts; t1——the start time of the exposure in seconds; t2——the stop time of the exposure in seconds; t2-t1——the exposure duration in seconds; P(t) ——the instantaneous absorbed power in watts; 3.3 axial isotropic the maximum deviation of the SAR when rotating around the major axis of the probe cover/case while the probe is exposed to a reference wave impinging from a direction along the probe major axis 3.4 basic restriction restrictions on human exposure to time-varying electric, magnetic, and electromagnetic fields that are based directly on established health effects NOTE Within the frequency range of this standard, the physical quantity used as a basic restriction is the specific absorption rate (SAR). 3.5 boundary effect (probe) a change in the sensitivity of an electric-field probe when the probe is located close to (less than one probe-tip diameter) media boundaries 3.6 complex permittivity the ratio of the electric flux density in a medium to the electric field strength at a point. The permittivity of biological tissues is frequency dependent.

Contents of YD/T 1644.1-2007

Foreword I 1 Scope 2 Normative References 3 Terms and definitions 4 Symbols and Abbreviated Terms 5 Measurement System Specifications 6 Protocol for SAR Assessment 7 Uncertainty Estimation 8 Measurement Report Annex A (Normative) Phantom Specifications Annex B (Normative) Calibration of the Measurement Instrumentation and Uncertainty Estimation Annex C (Normative) Post-processing Techniques and Uncertainty Estimation Annex D (Normative) SAR Measurement System Validation Annex E (Informative) Interlaboratory Comparisons Annex F (Informative) Definition of a Phantom Coordinate System and a Device Under Test Coordinate System Annex G (Informative) Validation Dipoles Annex H (Informative) Flat Phantom Annex I (Informative) Recommended Recipes for Phantom Head Tissue Equivalent Liquids Annex J (Informative) Measurement of the dielectric properties of liquids and uncertainty estimation Bibliography