Standard No.:	GB/T 42741-2023
English Name:	Measuring method for electromagnetic parameters of solid materials using air-freespace
Chinese Name:	固体材料使用自由空间法的电磁参数测量方法
Chinese Classification:	K04    Basic standards and general methods
Professional Classification:	GB    National Standard
Source Content Issued by:	SAMR; SAC
Issued on:	2023-05-23
Implemented on:	2023-12-1
Status:	valid
Target Language:	English
File Format:	PDF
Word Count:	7500 words
Translation Price(USD):	225.0
Delivery:	via email in 1 business day

GB/T 42741-2023 Measuring method for electromagnetic parameters of solid materials using air-freespace 1 Scope This document describes the general requirements and measuring methods for electromagnetic parameters of solid materials using the air-freespace method in the frequency range from 2 GHz to 110 GHz. This document is applicable to the measurement of complex relative permittivity, complex relative magnetic permeability and other parameters of homogeneous and isotropic solid materials using the air-freespace method. 2 Normative references The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 2900.74-2008 Electrotechnical terminology - Circuit theory GB/T 4365 Electrotechnical terminology - Electromagnetic compatibility GB/T 35679-2017 Measuring method for electromagnetic parameters of solid materials at microwave frequencies using waveguide 3 Terms and definitions For the purpose of this document, the terms and definitions given in GB/T 2900.74-2008, GB/T 4365 and GB/T 35679-2017 and the following apply. 3.1 complex relative permittivity εr Calculated by using formula (1): (1) where, j—— Imaginary number symbol; εr—— Complex relative permittivity; ε′r—— Real part of complex relative permittivity; ε″r—— Imaginary part of complex relative permittivity; ε0—— Vacuum permittivity, approximately equal to 8.85×10-¹² F/m; —— Electrical displacement vector, C/m²; —— Electric field intensity vector, V/m. Note 1: The complex relative permittivity of solid materials is determined by molecular polarization characteristics, charge movement characteristics and others. The solid material that this method applies is an isotropic solid material. Therefore, the complex relative permittivity at each frequency point is a single complex number. For anisotropic media, the complex relative permittivity is a three-dimensional spatial tensor. Note 2: Isotropy refers to the isotropy of electromagnetic characteristics. [Source: GB/T 35679- 2017, 3.3, modified] 3.2 complex relative magnetic permeability μr Calculated by using formula (2):

Contents Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Abbreviations 5 General 6 Method of measurement 7 Test report Annex A (Informative) Data recording form for the air-freespace method (sample)