Detail of GB/T 6113.106-2024

Introduction of GB/T 6113.106-2024

Specification for radio disturbance and immunity measuring apparatus and methods - Part 1-6 : Radio disturbance and immunity measuring apparatus - EMC antenna calibration 1 Scope This standard provides procedures and supporting information for the calibration of antennas for determining antenna factors (AF) that are applicable to antennas intended for use in radiated disturbance measurements. CISPR 16-1-6 has the status of a basic EMC Standard in accordance with IEC Guide 107. The AF of an antenna is influenced by nearby surroundings and by its position in space relative to the radiating source. This standard focuses on antenna calibrations that provide the AF in a free-space environment in the direction of the boresight of the antenna. The frequency range addressed is 9 kHz to 18 GHz. The relevant antenna types covered in this standard are monopole, loop, dipole, biconical, log-periodic dipole-array (LPDA), hybrid and horn antennas. Guidance is also provided on measurement uncertainties associated with each calibration method and configuration, and the test instrumentation used. 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 6113.104-2021 Specification for radio disturbance and immunity measuring apparatus and methods - Part 1-4 : Radio disturbance and immunity measuring apparatus - Antennas and test sites for radiated disturbance measurements (CISPR 16-1-4 :2019, IDT) GB/T 6113.105-2018 Specification for radio disturbance and immunity measuring apparatus and methods - Part 1-5 : Radio disturbance and immunity measuring apparatus - Antenna calibration sites and reference test sites for 5 MHz to 18 GHz (CISPR 16-1-5:2014, IDT) IEC 60050-161 International Electrotechnical Vocabulary (IEV) - Chapter 161: Electromagnetic compatibility Note: GB/T 4365-2003 Electrotechnical terminology - Electromagnetic compatibility [IEC 60050(161):1990, IDT] CISPR 16-1-2 Specification for radio disturbance and immunity measuring apparatus and methods - Part 1-2: Radio disturbance and immunity measuring apparatus- Coupling devices for conducted disturbance measurements) Note: GB/T 6113.102-2018 Specification for radio disturbance and immunity measuring apparatus and methods - Part 1-2 : Radio disturbance and immunity measuring apparatus - Coupling devices for conducted disturbance measurements (CISPR 16-1-2:2014, IDT) ISO/IEC Guide 98-3:2008 [Uncertainty of measurement-Part 3 : Guide to the expression of uncertainty in measurement (GUM:1995)] Note: GB/T 27418-2017 Guide to the evaluation and expression of uncertainty in measurement (ISO/IEC Guide 98-3:2008, MOD) 3 Terms, definitions and abbreviations 3.1 Terms and definitions For the purposes of this document, the following terms and definitions, as well as those given in IEC 60050-161, apply. Note: Full terms for abbreviations not already given in 3.1 are listed in 3.2. 3.1.1 Antenna terms 3.1.1.1 antenna transducer that converts the guided electromagnetic energy of the feed line into a radiated wave in space and vice versa Note: In the context of this standard, for antennas for which a balun is intrinsic to the functioning of the antenna, the term “antenna” includes the balun. 3.1.1.2 biconical antenna symmetric antenna formed by two conical radiating elements having a common axis, and adjacent vertices at which they are fed Note 1: For use in the VHF band, biconical antennas are usually made of two conical-shaped wire cages. Often each cage has a cross-bar connecting the centre conductor and one of the peripheral wires to remove a narrowband resonance. Such shorting cross-bars can affect the characteristics of the antenna above 215 MHz. For more details, see also A.4.3. Note 2: For the purpose of this standard, a biconical antenna for which the tip-to-tip length is between 1.3 m and 1.4 m (based on the MIL-STD-461 design with tip-to-tip length of 1.37 m [45]), is referred to as a classical biconical antenna, to distinguish from small biconicals whose upper frequency is above 300 MHz. 3.1.1.3 broadband antenna antenna having acceptable characteristics over a wide range of radio frequencies 3.1.1.4 calculable antenna dipole-like antenna of which the antenna factor of a single antenna, and the site insertion loss between a pair of antennas, may be calculated using either analytical or numerical (method of moments) techniques based on the dimensions, load impedance and geometrical parameters, and that can be verified by measurement Note: The calculable dipole antenna is a special case of calculable antenna; the good agreement between the analytical and numerical formulations confirms the very low uncertainties achievable with the linear dipole. A calculable dipole antenna is described in GB/T 6113.105-2018. 3.1.1.5 horn antenna antenna consisting of a waveguide section in which the cross-sectional area increases towards an open end, which is known as the aperture Note: Rectangular-waveguide pyramidal horn antennas are popular in the microwave frequency range above about 1 GHz. Double-ridged-waveguide horn antennas (DRH; sometimes also referred to as DRG horn, for double-ridged-guide) cover a very wide frequency range. The mainlobe of some DRH antennas splits into several beams at higher frequencies; for other details see the note in 9.5.1.3. 3.1.1.6 hybrid antenna antenna consisting of a wire-element log-periodic dipole array section and a broadband dipole section Note 1: The longest element of the LPDA (see 3.1.1.7) section is typically resonant at approximately 200 MHz, and the boom is lengthened at the open-circuit (rear) end to feed the connected broadband dipole (e.g. biconical or bowtie) section. Over the range 30 MHz to 200 MHz, the broadband dipole exhibits a performance similar to a biconical antenna, notably in the variation of Fa (h, p). Note 2: A common-mode choke is typically used at the open-circuit end (i.e. rear) of the boom, to minimize parasitic (unintended) RF currents on the outer conductor of the coaxial cable flowing into the measuring receiver. 3.1.1.7 log-periodic dipole array antenna LPDA antenna antenna comprising an array of linear dipole elements whose lengths and spacings increase logarithmically with frequency from the tip to the larger end of the antenna 3.1.1.8 monopole antenna linear vertical antenna that is normally placed on a large horizontal conducting ground plane, which then has characteristics like a vertically polarized dipole antenna Note 1: The monopole antenna is a combination of a vertical rod and matching unit at its base. Provided that the combined height is less than λ/8 (λ is wavelength, in m), the ECSM is a valid method for measuring the AF. Note 2: The term “rod” describes the metal rod that is detachable from the matching unit at the point where it is replaced by the dummy antenna in the ESCM. 3.1.1.9 resonant dipole antenna tuned dipole antenna antenna consisting of two straight collinear conductors of equal length, placed end to end, separated by a small gap constituting a balanced feed, with each conductor approximately a quarter-wavelength long such that at the specified frequency the input impedance of the antenna measured across the gap has zero reactance when the dipole is located in free space Note: A resonant dipole antenna is also a calculable antenna (see 3.1.1.4). In this standard the term “linear dipole” implies “two straight collinear conductors,” in contrast to the biconical dipole, or array of dipoles as in the LPDA antenna. 3.1.1.10 standard antenna STA antenna for which the AF is calculated or measured precisely Note 1: An STA may be a calculable antenna (see 3.1.1.4) such as specified in 4.3 of GB/T 6113.105-2018; alternatively an STA can be an antenna of a type similar to the AUC that has been calibrated to lower uncertainties than is required for the AUC. The three antenna method (TAM) is an example of methods for precise measurement of the AF of an STA. Note 2: An STA is used for measurements by the standard antenna method (SAM) (see 4.3.5, etc.). An STA is mechanically robust such that reproducibility of AF to better than ± 0.2 dB is maintained with continuous use of the STA. Balance and cross-polar criteria applicable to the STA are found in 6.3.2 and 6.3.3. 3.1.1.11 antenna under calibration AUC antenna being calibrated, and as distinguished from the paired antenna(s) that are used in calibration measurements of the antenna under calibration Note : See 3.1.1.12 for the definition of paired antenna. 3.1.1.12 paired antenna antenna used in antenna calibration that covers the frequency range of the AUC and has similar directivity as the AUC Note 1: Example antenna pairs for the TAM include biconical-biconical, biconical-dipole, biconical-hybrid, LPDA-hybrid, LPDA-LPDA, LPDA-horn. Note 2: The distinction in the function of a paired antenna in the TAM and the SAM is given in 6.2.1. Note 3: See 8.3.3 for description of similarity of antennas. 3.1.1.13 balun device for transforming an unbalanced transmission line to a balanced transmission line and vice-versa Note 1: A balun is used, for example, to couple balanced antenna elements to an unbalanced feed line, such as a coaxial cable. A balun may exhibit inherent impedance transformation differing from unity. Note 2: In this standard the word balun is also used to refer to the handle of biconical or hybrid antennas, usually in the form of a metal tube or pole. 3.1.1.14 antenna directivity ratio of the radiation intensity of an antenna in its boresight direction to the average radiation intensity Note 1: See 3.1.1.18 for boresight direction, and 3.1.1.1 5 for radiation pattern. Note 2: The default definition of directivity is relative to the isotropic radiation condition (i.e. for the average radiation intensity, as in this definition), with the unit symbol dBi. When the reference is a half-wave dipole, which has a directivity of 1.64, the unit symbol is dBd [y (dBd) = x (dBi) – 2.15 dB).

Contents of GB/T 6113.106-2024