GB/T 17626 consists of the following parts, under the general title Electromagnetic Compatibility — Testing and Measurement Techniques:
— GB/T 17626.1-2006 Electromagnetic Compatibility — Testing And Measurement Techniques — Overview of Immunity Tests;
— GB/T 17626.2-2018 Electromagnetic Compatibility — Testing And Measurement Techniques — Electrostatic Discharge Immunity Test;
— GB/T 17626.3-2016 Electromagnetic Compatibility — Testing And Measurement Techniques — Radiated, Radio-frequency, Electromagnetic Field Immunity Test;
— GB/T 17626.4-2018 Electromagnetic Compatibility — Testing And Measurement Techniques — Electrical Fast Transient/Burst Immunity Test;
— GB/T 17626.5-2008 Electromagnetic Compatibility — Testing And Measurement Techniques — Surge (Impact) Immunity Test;
— GB/T 17626.6-2017 Electromagnetic Compatibility — Testing And Measurement Techniques — Immunity To Conducted Disturbances, Induced by Radio-frequency Fields;
— GB/T 17626.7-2008 Electromagnetic Compatibility — Testing And Measurement Techniques — General Guide on Harmonics and Interharmonics Measurements And Instrumentation For Power Supply Systems And Equipment Connected Thereto;
— GB/T 17626.8-2006 Electromagnetic Compatibility — Testing And Measurement Techniques — Power Frequency Magnetic Field Immunity Test;
— GB/T 17626.9-2011 Electromagnetic Compatibility — Testing And Measurement Techniques — Pulse Magnetic Field Immunity Test;
— GB/T 17626.10-2017 Electromagnetic Compatibility — Testing And Measurement Techniques — Damped Oscillatory Magnetic Field Immunity Test;
— GB/T 17626.11-2008 Electromagnetic Compatibility — Testing And Measurement Techniques — Voltage Dips, Short Interruptions And Voltage Variations Immunity Tests;
— GB/T 17626.12-2013 Electromagnetic Compatibility — Testing And Measurement Techniques — Oscillatory Waves Immunity Test;
— GB/T 17626.13-2006 Electromagnetic Compatibility — Testing And Measurement Techniques — Harmonics and Interharmonics Including Mains Signalling At A.C. Power Port, Low Frequency Immunity Test;
— GB/T 17626.14-2005 Electromagnetic Compatibility — Testing And Measurement Techniques — Voltage Fluctuation Immunity Test;
— GB/T 17626.15-2011 Electromagnetic Compatibility — Testing And Measurement Techniques — Flickermeter — Functional And Design of Specifications;
— GB/T 17626.16-2007 Electromagnetic Compatibility — Testing And Measurement Techniques — Test For Immunity To Conducted, Common Mode Disturbances In The Frequency Range 0 Hz To 150 kHz;
— GB/T 17626.17-2005 Electromagnetic Compatibility — Testing And Measurement Techniques — Ripple on D.C. Input Power Port Immunity Test;
— GB/T 17626.18-2016 Electromagnetic Compatibility — Testing And Measurement Techniques — Oscillatory Waves Immunity Test;
— GB/T 17626.20-2014 Electromagnetic Compatibility — Testing And Measurement Techniques — Emission And Immunity Testing In Transverse Electromagnetic (TEM) Waveguide;
— GB/T 17626.21-2014 Electromagnetic Compatibility — Testing And Measurement Techniques — Reverberation Chamber Test Methods;
— GB/T 17626.22-2017 Electromagnetic Compatibility — Testing And Measurement Techniques — Radiated Emissions and Immunity Measurements In Fully Anechoic Rooms (FARs);
— GB/T17626.24-2012 Electromagnetic Compatibility — Testing And Measurement Techniques — Test Methods For Protective Devices For HEMP Conducted Disturbance;
— GB/T 17626.27-2006 Electromagnetic Compatibility — Testing And Measurement Techniques — Unbalance Immunity Test;
— GB/T 17626.28-2006 Electromagnetic Compatibility — Testing And Measurement Techniques — Variation of Power Frequency Immunity Test;
— GB/T 17626.29-2006 Electromagnetic Compatibility — Testing And Measurement Techniques — Voltage Dips, Short Interruptions And Voltage Variations On D.C. Input Power Port Immunity Tests;
— GB/T 17626.30-2012 Electromagnetic Compatibility — Testing And Measurement Techniques — Power Quality Measurement Methods;
— GB/T 17626.34-2012 Electromagnetic Compatibility — Testing And Measurement Techniques — Voltage Dips, Short Interruptions And Voltage Variations Immunity Tests For Equipment with Mains Current More Than 16 A Per Phase;
This part is Part 3 of GB/T 17626.
This Part is drafted in accordance with the rules given in GB/T 1.1-2009.
This part replaces GB/T 17626.3-2006 Electromagnetic Compatibility — Testing and Measurement Techniques — Radiated, Radio-frequency, Electromagnetic Field Immunity Test in whole.
The following technical deviations have been made with respect to GB/T 17626.3-2006:
— The original terms 4.11 “stripline” and 4.15 “spurious radiation” are deleted from Clause 4 “Terminology and Definitions”;
— The original Tables 1 and 2 in Clause 5 are merged into Table 1 “Test levels related to general purpose, digital radio telephones and other RF emitting devices”;
— In 5. 2, the high frequency range for test levels related to the protection against RF emissions from digital radio telephones and other RF emitting devices is extend form 2 GHz to 6 GHz;
— In Clause 6, the requirements for power amplifiers are modified;
— In 6.2 “Calibration of field”, the requirements for uniform field area for application of full illumination, partial illumination and independent windows method are added;
— In 6.2.1 “Constant field strength calibration method”, step j) is added to confirm the test system;
— In 6.2.2 “Constant power calibration method”, step m) is added to confirm the test system;
— In Annex B “Field Generating Antennas”, circularly polarized antenna is deleted;
— The original Annex D “Other Test Methods — TEM Cells and Striplines” is deleted;
— The original Annex I is changed to Annex G, and Table G.3 is added;
— The original Annex H is changed to Annex F;
— The original Annex J is changed to Annex H;
— The original Annex K is changed to Annex J;
— The original Annex F and Annex G are merged into Annex E;
— Annex I “Calibration Method for E-field Probes” is added;
— Annex J “Measurement Uncertainty due to Test Instrumentation” is added.
This part is identical with International Standard IEC 61000-4-3:2010 Electromagnetic Compatibility (EMC) — Part 4-3: Testing And Measurement Techniques — Radiated, Radio-frequency, Electromagnetic Field Immunity Test.
The Chinese documents identical to the normative international documents given in this part are as follows:
— GB/T 4365-2003 Electrotechnical Terminology — Electromagnetic Compatibility [IEC 60050 (161):1990, IDT]
— GB/T 17626. 6-2008 Electromagnetic Compatibility — Testing and Measurement Techniques — Immunity To Conducted Disturbances, Induced By Radio-frequency Fields (IEC 61000-4-6:2006, IDT).
This part was proposed by and is under the jurisdiction of the National Technical Committee on Electromagnetic Compatibility of Standardization Administration of China (SAC/TC 246).
Drafting organizations of this part: Shanghai Electrical Apparatus Research Institute, Shanghai Institute of Measurement and Testing Technology, Shanghai Institute of Process Automation & Instrumentation, Beijing Institute of Medical Device Testing, Dongshuo Testing Technology (Suzhou) Co., Ltd. and Shanghai Sanki Electronic Industries Co., Ltd.
Chief drafters of this part: Zheng Junqi, Liu Yuan, Gong Cheng, Wang Ying, Meng Zhiping, Xiao Xiao, Yuan Mingcong, Ye Qiongyu, Shou Jianxia and Qian Feng.
The previous editions of this part are as follows:
— GB/T 17626.3-1992, GB/T 17626. 3-1998, GB/T 17626. 3-2006.
Electromagnetic Compatibility — Testing And Measurement Techniques — Radiated, Radio-frequency, Electromagnetic Field Immunity Test
1 Scope
This part of GB/T 17626 is applicable to the immunity requirements of electrical and electronic equipment to radiated electromagnetic energy. It establishes test levels and the required test procedures.
The object of this part is to establish a common reference for evaluating the immunity of electrical and electronic equipment when subjected to radiated, radio-frequency electromagnetic fields. The test method documented in this part describes a consistent method to assess the immunity of an equipment or system against a defined phenomenon.
Note 1: As described in GB/Z 18509, this is a basic EMC publication for use by product committees. As also stated in GB/Z 18509, the product committees are responsible for determining whether this immunity test standard should be applied or not, and if applied, they are responsible for determining the appropriate test levels and performance criteria. National Technical Committee on Electromagnetic Compatibility of Standardization Administration of China (SAC/TC 246) and its sub-committees are prepared to co-operate with product committees in the evaluation of the value of particular immunity tests for their products.
This part deals with immunity tests related to the protection against RF electromagnetic fields from any source.
Particular considerations are devoted to the protection against radio-frequency emissions from digital radiotelephones and other RF emitting devices.
Note 2: Test methods are defined in this part for evaluating the effect that electromagnetic radiation has on the equipment concerned. The simulation and measurement of electromagnetic radiation is not adequately exact for quantitative determination of effects. The test methods defined are structured for the primary objective of establishing adequate repeatability of results at various test facilities for qualitative analysis of effects.
This part is an independent test method. Other test methods may not be used as substitutes for claiming compliance with this part.
2 Normative References
The following referenced documents are indispensable for the application 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.
IEC 60050(161) International Electrotechnical Vocabulary (IEV) — Chapter 161: Electromagnetic Compatibility
IEC 61000-4-6 Electromagnetic Compatibility (EMC) — Part 4-6: Testing And Measurement Techniques — Immunity To Conducted Disturbances, Induced By Radio-frequency Fields
3 Terms and Definitions
For the purposes of this document, the following terms and definitions apply.
3.1
amplitude modulation
process by which the amplitude of a carrier wave is varied following a specified law
3.2
anechoic chamber
shielded enclosure which is lined with radio-frequency absorbers to reduce reflections from the internal surfaces
3.2.1
fully anechoic chamber
shielded enclosure whose internal surfaces are totally lined with anechoic material
3.2.2
semi-anechoic chamber
shielded enclosure where all internal surfaces are covered with anechoic material with the exception of the floor, which shall be reflective (ground plane)
3.2.3
modified semi-anechoic chamber
semi-anechoic chamber which has additional absorbers installed on the ground plane
3.3
antenna
transducer which either emits radio-frequency power into space from a signal source or intercepts an arriving electromagnetic field, converting it into an electrical signal
3.4
balun
device for transforming an unbalanced voltage to a balanced voltage or vice versa
[IEV 60050(161)]
3.5
continuous waves (CW)
electromagnetic waves, the successive oscillations of which are identical under steady-state conditions, which can be interrupted or modulated to convey information
3.6
electromagnetic (EM) wave
radiant energy produced by the oscillation of an electric charge characterized by oscillation of the electric and magnetic fields
?
3.7
far field
region where the power flux density from an antenna approximately obeys an inverse square law of the distance.
For a dipole this corresponds to distances greater than λ/2π, where λ is the wavelength of the radiation
3.8
field strength
Field strength (namely electric field strength) is the ratio of the electrostatic force to the electric charge at a point in the electric field, which is used to indicate the strength and direction of the electric field.
The term "field strength" is applied only to measurements made in the far field. The measurement may be of either the electric or the magnetic component of the field and may be expressed as V/m, A/m or W/m2; any one of these may be converted into the others.
For measurements made in the near field, the term "electric field strength" or "magnetic field strength" is used according to whether the resultant electric or magnetic field, respectively, is measured. In this field region, the relationship between the electric and magnetic field strength and distance is complex and difficult to predict, being dependent on the specific configuration involved. Inasmuch as it is not generally feasible to determine the time and space phase relationship of the various components of the complex field, the power flux density of the field is similarly indeterminate.
3.9
frequency band
continuous range of frequencies extending between two limits
3.10
Ec
field strength applied for calibration
3.11
Et
carrier field strength applied for testing
3.12
full illumination
test method in which the EUT face being tested fits completely within the UFA (Uniform Field Area, see the test methods covered in 3.27).
This test method may be applied for all test frequencies
3.13
human body-mounted equipment
equipment which is intended for use when attached to or held in close proximity to the human body.
This term includes hand-held devices which are carried by people while in operation (e.g. pocket devices) as well as electronic aid devices and implants
3.14
independent windows method
test method (using 0.5 m × 0.5 m UFA) in which the EUT face being tested does not fit completely within the UFA.
This test method may be applied for test frequencies greater than 1 GHz
3.15
induction field
predominant electric and/or magnetic field existing at a distance d < λ/2π, where λ is the wavelength, and the physical dimensions of the source are much smaller than distance d
3.16
intentional RF emitting device
device which radiates (transmits) an electromagnetic field intentionally. Examples include digital mobile telephones and other radio devices
3.17
isotropic
having properties of equal values in all directions
3.18
maximum RMS value
highest short-term RMS value of a modulated RF signal during an observation time of one modulation period.
The short-term RMS is evaluated over a single carrier cycle. For example, in Figure 1 b), the maximum RMS voltage is:
(1)
3.19
non-constant envelope modulation
RF modulation schemes in which the amplitude of the carrier wave varies slowly in time compared with the period of the carrier itself. Examples include conventional amplitude modulation and TDMA
3.20
Pc
forward power needed to establish the calibration field strength
3.21
partial illumination
test method (using a minimum sized UFA of 1.5 × 1.5 m) in which the EUT face being tested does not fit completely within the UFA.
This test method may be applied for all test frequencies.
3.22
polarization
orientation of the electric field vector of a radiated field
3.23
shielded enclosure
screened or solid metal housing designed expressly for the purpose of isolating the internal from the external electromagnetic environment. The purpose is to prevent outside ambient electromagnetic fields from causing performance degradation and to prevent emission from causing interference to outside activities
3.24
sweep
continuous or incremental traverse over a range of frequencies
3.25
TDMA (time division multiple access)
time multiplexing modulation scheme which places several communication channels on the same carrier wave at an allocated frequency. Each channel is assigned a time slot during which, if the channel is active, the information is transmitted as a pulse of RF power. If the channel is not active no pulse is transmitted, thus the carrier envelope is not constant. During the pulse, the amplitude is constant and the RF carrier is frequency- or phase-modulated
3.26
transceiver
combination of radio transmitting and receiving equipment in a common housing
3.27
uniform field area (UFA)
hypothetical vertical plane of the field calibration in which variations are acceptably small.
The purpose of field calibration is to ensure the validity of the test result. See 6.2
4 General
Most electronic equipment is, in some manner, affected by electromagnetic radiation. This radiation is frequently generated by such general purpose sources as the small hand-held radio transceivers that are used by operating, maintenance and security personnel, fixed-station radio and television transmitters, vehicle radio transmitters, and various industrial electromagnetic sources.
In recent years there has been a significant increase in the use of radio telephones and other RF emitting devices operating at frequencies between 0.8 GHz and 6 GHz. Many of these services use modulation techniques with a non-constant envelope (e.g. TDMA). See 5.2.
In addition to electromagnetic energy deliberately generated, there is also radiation caused by devices such as welders, thyristors, fluorescent lights, switches operating inductive loads, etc. For the most part, this interference manifests itself as conducted electrical interference and, as such, is dealt with in other parts of the IEC 61000-4 standard series. Methods employed to prevent effects from electromagnetic fields will normally also reduce the effects from these sources.
The electromagnetic environment is determined by the strength of the electromagnetic field. The field strength is not easily measured without sophisticated instrumentation nor is it easily calculated by classical equations and formulas because of the effect of surrounding structures or the proximity of other equipment that will distort and/or reflect the electromagnetic waves.
5 Test Levels
The test levels are given in Table 1.
Table 1 Test Levels Related to General Purpose, Digital Radio Telephones and Other RF Emitting Devices
Level Test field strength (V/m)
1 1
2 3
3 10
4 30
X Special
X is an open test level and the associated field strength may be any value. This level may be given in the product standard.
This part does not suggest that a single test level is applicable over the entire frequency range. Product committees shall select the appropriate test level for each frequency range needing to be tested as well as the frequency ranges. See Annex E for a guidance for product committees on the selection of test levels.
The test field strength column gives values of the unmodulated carrier signal. For testing of equipment, this carrier signal is 80% amplitude modulated with a 1 kHz sine wave to simulate actual threats (see Figure 1). Details of how the test is performed are given in Clause 8.
5.1 Test Levels Related to General Purposes
The tests are normally performed without gaps in the frequency range 80 MHz to 1000 MHz.
Note 1: Product committees may decide to choose a lower or higher transition frequency than 80 MHz between IEC 61000-4-3 and IEC 61000-4-6 (see Annex G).
Note 2: Product committees may select alternative modulation schemes for equipment under test.
Note 3: IEC 61000-4-6 also defines test methods for establishing the immunity of electrical and electronic equipment against radiated electromagnetic energy. It covers frequencies below 80 MHz.
5.2 Test Levels Related to the Protection Against RF Emissions from Digital Radio Telephones and Other RF Emitting Devices
The tests are normally performed in the frequency ranges 800 MHz to 960 MHz and 1.4 GHz to 6 GHz.
The frequencies or frequency bands to be selected for the test are limited to those where mobile radio telephones and other intentional RF emitting devices actually operate. It is not intended that the test needs to be applied continuously over the entire frequency range from 1.4 GHz to 6 GHz. For those frequency bands used by mobile radio telephones and other intentional RF emitting devices, specific test levels may be applied in the corresponding frequency range of operation.
Also if the product is intended to conform only to the requirements of particular countries, the measurement range 1.4 GHz to 6 GHz may be reduced to cover just the specific frequency bands allocated to digital mobile telephones and other intentional RF emitting devices in those countries. In this situation, the decision to test over reduced frequency ranges shall be documented in the test report.
Note 1: Annex A contains an explanation regarding the decision to use sine wave modulation for tests related to protection against RF emissions from digital radio telephones and other intentional RF emitting devices.
Note 2: Annex E contains guidance with regard to selecting test levels.
Note 3: The measurement ranges for Table 2 are the frequency bands generally allocated to digital radio telephones (Annex G contains the list of frequencies known to be allocated to specific digital radio telephones at the time of publication).
Note 4: The primary threat above 800 MHz is from radio telephone systems and other intentional RF emitting devices with power levels similar to that of radio telephones. Other systems operating in this frequency range, e.g. radio LANs operating at 2.4 GHz or higher frequencies, are generally very low power (typically lower than 100 mW), so they are much less likely to present significant problems.
Foreword II
1 Scope
2 Normative References
3 Terms and Definitions
4 General
5 Test Levels
5.1 Test Levels Related to General Purposes
5.2 Test Levels Related to the Protection Against RF Emissions from Digital Radio Telephones and Other RF Emitting Devices
6 Test Equipment
6.1 Description of the Test Facility
6.2 Calibration of Field
7 Test Setup
7.1 Arrangement of Table-top Equipment
7.2 Arrangement of Floor-standing Equipment
7.3 Arrangement of Wiring
7.4 Arrangement of Human Body-mounted Equipment
8 Test Procedure
8.1 Laboratory Reference Conditions
8.2 Execution of the Test
9 Evaluation of Test Results
10 Test Report
Annex A (Informative) Rationale for the Choice of Modulation for Tests Related to the Protection against RF Emissions from Digital Radio Telephones
Annex B (Informative) Field Generating Antennas
Annex C (Informative) Use of Anechoic Chambers
Annex D (Informative) Amplifier Non-linearity and Example for the Calibration Procedure According to
Annex E (Informative) Guidance for Product Committees on the Selection of Test Levels
Annex F (Informative) Selection of Test Methods
Annex G (Informative) Description of the Environment
Annex H (Normative) Alternative Illumination Method for Frequencies Above 1 GHz (“Independent Windows Method”)
Annex I (Informative) Calibration Method for E-field Probes
Annex J (Informative) Measurement Uncertainty due to Test Instrumentation
電磁兼容試驗和測量技術
射頻電磁場輻射抗擾度試驗
1范圍
GB/T 17626的本部分適用于電氣、電子設備的電磁場輻射抗擾度要求,規定了試驗等級和必要的 試驗程序。
本部分的目的是建立電氣、電子設備受到射頻電磁場輻射時的抗擾度評定依據。在本部分中給出 的試驗方法描述了評估設備或系統抵抗一定環境的抗擾度的符合性方法。
注1：如GB/Z 18509所述.本部分是供冇關專業標準化技術委員會使用的基礎EMC出版物。同時在GB/Z 18509 中規定,有美專業標準化技術委員會負責確定此抗擾度測試標準是否適用.如適用，他們右責任確定適合的試 驗等級及性能判據。全國電磁兼容標準化技術委員會(S/\C/TC 246＞及其分會與右美專業標準化技術委員會 合作.以評估對其產品的特定抗擾度試驗的試驗等級及性能判據。
本部分適用丁 ?防止所有發射源的射頻電磁場的抗擾度試羚。
特別關注對防止數字無線電話和其他射頻發射裝置的射頻輻射。
注2：本部分規定了 if EUT在電磁輻射狀況卜受影響程度的試驗方法。電磁輻射的模擬和測政對定拭確定這種 影響程度是不夠準確的。所定義試繾方法的宗旨是為定性分析建立一個對各種EUT均可獲得度好重復性洲I 員結果的方法。
本部分是一個獨立的試驗方法。不可使用其他試驗方法替代來聲稱符合本部分。
2規范性引用文件
下列文件對于本文件的應用是必不町少的。凡是注日期的引用文件，僅注日期的版本適用于本文 件。凡是不注日期的引用文件，其最新版本(包括所有的修改單)適用于本文件。
IEC 60050(161) 國際電工詞匯(IEV) 第 161 章：電磁兼容 International Electrotechnical Vo?cabulary (IEV)—Chapter 161: Electromagnetic compatibility]
IEC 61000-4-6電磁兼容 第4-6部分 試驗與測最技術-射頻場感應的傳導干擾抗擾度[Elec?tromagnetic compatibilitity ( EM(')一Part 4-6 : Testing and measurement techniques—Immunity to conducted di st ur bances. induced by radio frequency fields]
3術語和定義
下列術語和定義適用于本文件。
3. 1
調幅 amplitude modulation
載波幅度按給定規律變化的過程。
3.2
電波暗室 anechoic chamber
安裝吸波材料用以降低內表面電波反射的屏蔽室。
3.2. 1
全電波暗室 fully anechoic chamber
內表而全部安裝吸波材料的屏蔽室。
3.2.2
半電波暗室 scnii-ancchoic chamber
除地面安裝反射接地平板外.其余內表面均安裝吸波材料的屏蔽室。
3.2.3
可調式半電波暗室 modified semi-anechoic chamber
在地面反射接地平板上附加吸波材料的半電波暗室。
3.3
天線 antenna
-?種將信號源射頻功率發射到空間或截獲空間電磁場轉變為電信號的轉換器。
3.4
平衡?不平衡轉換器balun
用來將不平衡電壓與平衡電壓相互轉換的裝置。
| IEC 60050(161)]
3.5
連續波(CW) continuous waves (CW)
在穩態條件下，完全相同的連續振蕩的電磁波，可以通過中斷或調制來傳遞信息?
3.6
電磁波 electromagnetic (EM) wave
由電荷振蕩所產生的輻射能員.其特征是電磁場的振蕩。
3.7
遠場 far field
由天線發射的功率通量密度近似地與距離的平方呈反比關系的場域。
對于偶極子天線來說，相當丁大于"臨的距離的場域，A為輻射波長。
3.8
場強 field strength
場強即電場強度.是放入電場中某點的電荷所受靜電力與它的電荷量的比值.用來表示電場的強弱 和方向的物理量。
??場強I”一詞僅適用于遠場測雖。測雖的可以是電場分星或磁場分墾,可用V/m.A/m或W/m2表 示.單位間可相互換算。
近場測址時?術語“電場強度”或“磁場強度"的使用取決于是否分別測量電場或磁場的分量。近場 中.電場強度和磁場強度與距離的關系是復雜的.并旦很難預測.它涉及場中特定的布置。因此.一般不 可能確定復合場的分雖在時間和空間相位上的變化，功率通雖密度同樣也是不確定的。
3.9
頻帶 frequency band
兩個限定的頻率點之間頻率延伸的連續區間。
3. 10
校準用場強。
3. 11
&
測試用的載波場強。
3. 12
完全照射 full illumination
EUT的被測試面完全被UFA（均勻場域.見3. 27所覆蓋的試驗方法）。
該試驗方法町適用于所冇試驗頻率。
3. 13
人身攜帶設備 human hody-mounted equipment
用于人身附屬或近距離攜帶的設備。
包括人們攜帶的正在運行中的手持式設備（例如袖珍設備）和電子輔助裝置以及植入式裝置。
3. 14
獨立窗口法 independent windows method
當EUT的被測試面不能完全被UFA所覆蓋時所采用的試驗方法（使用0. 5 mXO. 5 m的UFA）。 該試驗方法可適用于1 GHz以上的試驗頻率。
3. 15
感應場 induced field
電場和/或磁場的主要能量存在于距離J
