1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T K.70 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 5 (04/2016) SERIES K: PROTECTION AGAINST INTERFERENCE Mitigation techniques to limit human exposure to EMFs in the vicinity of radiocommunication stations Amend
2、ment 5: Appendix I New version v.6.01 of the software EMF-estimator Recommendation ITU-T K.70 (2007) Amendment 5 Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) i Recommendation ITU-T K.70 Mitigation techniques to limit human exposure to EMFs in the vicinity of radiocommunication stations Amendment 5 Appendi
3、x I New version v.6.01 of the software EMF-estimator Summary Amendment 5 to Recommendation ITU-T K.70 consists of a new version (v.6.01) of the software EMF-estimator, which constitutes Appendix I of Recommendation ITU-T K.70 (2007). The software was developed in 2007 and since then it has been upda
4、ted four times (in 2009, 2011, 2013 and 2014) following the requirements expressed during ITU-T meetings and workshops. A new version v.6.01 of the EMF-estimator has been approved, which adds two new features: the possibility to make calculation on the vertical grid the inclusion of the cylindrical
5、model which allows for substantial reduction of the area excluded from calculations, however with the higher level of overestimation. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T K.70 2007-06-29 5 11.1002/1000/9140 1.1 ITU-T K.70 (2007) Amd.1 2009-05-29 5 11.1002/1000/100
6、36 1.2 ITU-T K.70 (2007) Amd.2 2011-05-05 5 11.1002/1000/11351 1.3 ITU-T K.70 (2007) Amd.3 2013-02-07 5 11.1002/1000/11906 1.4 ITU-T K.70 (2007) Amd.4 2014-12-19 5 11.1002/1000/12441 1.5 ITU-T K.70 (2007) Amd. 5 2016-04-27 5 11.1002/1000/12978 * To access the Recommendation, type the URL http:/handl
7、e.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the
8、field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standar
9、dizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is cove
10、red by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indic
11、ate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieve
12、d when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PR
13、OPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asser
14、ted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that
15、this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2016 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. I
16、TU-T K.70 (2007)/Amd.5 (04/2016) iii Table of Contents Page Appendix I Software EMF-estimator 1 I.1 Applicability of the EMF-estimator . 1 I.2 Typical situation . 3 I.3 Software description . 3 I.4 Compliance distances . 6 I.5 Coefficient concerning transmitter power 6 I.6 Library radiation patterns
17、 of the antenna systems . 7 I.7 Examples of calculations 7 I.8 Additional comments 7 I.9 System requirements 7 Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) 1 Recommendation ITU-T K.70 Mitigation techniques to limit human exposure to EMFs in the vicinity of radiocommunication stations Amendment 5 Appendix
18、I New version v.6.01 of the software EMF-estimator Appendix I Software EMF-estimator (This appendix does not form an integral part of this Recommendation.) The EMF-estimator software has been developed in order to support the application of the methods described in this Recommendation1. It may help
19、to make an estimation of the cumulative exposure in the vicinity of transmitting stations in the case of many different transmitting systems operating at different frequencies. The EMF-estimator is one of the available programs which may be used for that purpose. This software is not intended to be
20、used, and in fact cannot be used, for any certification procedure of the transmitting equipment. I.1 Applicability of the EMF-estimator The EMF-estimator software uses the point source model (described in clause 5.3) and exploits the radiation patterns contained in the attached library or introduced
21、 by the user. The radiation pattern may have a full, two-variable 3D form f(,) (a function of azimuth and elevation angles) or may be represented by the horizontal and vertical radiation patterns HRP() and VRP(). The credibility of the calculation is strongly affected by the model used and depends o
22、n the region under investigation and available data concerning a transmitting antenna and operating channels (carriers). Generally, the results of calculations are adequate in the far-field region and give acceptable results in most of the radiating near-field region. Depending on the direction, one
23、 may expect an overestimation or underestimation of the field in the radiating near-field region. The EMF-estimator should not be used for calculations in the reactive near-filed region because the models on which it is based are too simple to describe correctly the real conditions determining the E
24、MFs distribution, so for this region the results are not presented by the software. The calculations are more credible if a full radiation pattern f(,) is used. Sufficiently good estimations are also achieved if horizontal and vertical radiation patterns HRP() and VRP() are applied. The influence of
25、 the radiation pattern and, consequently, the importance of the exactness of its knowledge grows with increasing transmitting antenna gain. In version v6.0 of the software, the area in which results of calculations are adequate has substantially increased because the new limitations are based on the
26、 cylindrical model of the antennas. It is not required to input additional data. EMF-estimator calculates required parameters (cylindrical model) using antennas radiation pattern that is loaded by the user. This new feature is valid for the antennas 1 The EMF-estimator software is included as an ele
27、ctronic attachment to this amendment. 2 Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) represented by the horizontal and vertical radiation patterns HRP() and VRP(). In the expanded area of the software validity the level of overestimation can be higher. In the EMF-estimator package, the library is included
28、, containing examples of the radiation pattern for many typical radiocommunication and broadcast services. One should note, however, that if the radiation patterns are used for antennas which are only similar to those in operation, the results of the calculations should be regarded as an estimation
29、only. In many practical cases in which radiation levels are far under the limits, such estimation can be sufficient. The input data for the EMF-estimator contains the operating frequency and the size of each transmitting antenna. Based on this data, the area around an object is split into regions of
30、 the field. For the area too close to the transmitting antennas, appropriate information appears on the screen. In practice, only the area in very close proximity to the transmitting antenna (usually with no access for people) cannot be analysed with the use of the EMF-estimator. The EMF-estimator e
31、valuates: electric field strength; magnetic field strength; the equivalent plane-wave power flux-density; near- and far-field region distances; compliance distances (for general public and occupational exposure); cumulative exposure coefficients Wt and We; reference levels along a line defined by th
32、e user and with presented contribution of each component (each source); the total exposure at a height above the ground level defined by the user in a form of the planar chart (horizontal grid); there is a possibility to place this chart against the Google map; the total exposure on the azimuth defi
33、ned by the user in a form of the planar chart (vertical grid); reference levels related to the ICNIRP or user defined limits. The program uses a library of the radiation patterns for typical antenna systems but there is an opportunity to introduce user-prepared data concerning the transmitting anten
34、na radiation pattern. The accuracy of the results of calculations is strongly affected by the accuracy of the input data concerning the transmitting equipment (mainly transmitting antennas). The problem is that, in many cases, the data, especially concerning the radiation patterns, are not available
35、 or known with limited accuracy. Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) 3 I.2 Typical situation Figure I.1 explains some terms used in the EMF-estimator. Figure I.1 Explanation of some terms used in the EMF-estimator I.3 Software description Figure I.2 shows the main screen of the EMF-estimator with
36、 opened project “Figure_8_1“. It consists of three tabs. In tab “Radiation sources“ there are names and input data concerning each operating frequency. On this page, one can choose the antenna system radiation pattern. If the blank field is chosen, then the HRP and VRP for each observation point hav
37、e to be introduced manually. If there is no information available concerning the transmitting radiation pattern, the “isotropic“ radiation pattern may be used, but this will lead to an overestimation of the field, growing with the antenna gain. It is also possible to choose the 3D radiation pattern.
38、 4 Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) Figure I.2 Main screen of the EMF-estimator with “Radiating sources“ tab opened Tab “Source XXX“ (Figure I.4) contains results of calculations for the XXX source of radiation (operating frequency). There is also a button on this screen, allowing for the visu
39、alization of the distribution of the equivalent plane-wave power density, produced at a chosen operating frequency, as a function of the distance along an observation line defined by the user. The “Antenna orientation and calculations“ Tab (Figure I.3) is designed to input the location of each trans
40、mitting antenna and the parameters of the user-defined observation points line. The data has to be written down in respective blank spaces. In the main toolbar, there are inputs to options such as: open/save project, import new radiation pattern, add/remove sources, print, chart with the ICNIRP refe
41、rence limits and cumulative exposure, which makes possible the calculation of the cumulative exposure for all the sources introduced in the project (see in main toolbar). Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) 5 Figure I.3 Screen of the EMF-estimator with “Antenna orientation and calculations“ tab o
42、pened Figure I.4 Screen of the EMF-estimator with “Source XXX“ tab opened 6 Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) Figure I.5 Screen of the EMF-estimator the results of the cumulative exposure calculations It should be noted that the results of calculations are strongly affected by the exactness of
43、the input data and all the limitations of the model. Since the radiation patterns are given on the one degree lattice then, for very high gain antennas, the curves may not be smooth because, for quickly varying functions, one degree step can be too big. I.4 Compliance distances Tab “Source XXX“ also
44、 presents the results of the calculation of the compliance distances. If the distance is greater than 0.6*D2/ then the results are shown. If it is smaller, then the overestimating value is shown, i.e., the lower value of the two: at the distances 0.6*D2/ and at distance at which the radiation limit
45、is achieved under the assumption of isotropic radiation pattern (f(,) = 1). It should be noted that, in some cases, such an overestimation may be quite big. I.5 Coefficient concerning transmitter power An additional explanation is needed for the parameter “Type of service coefficient nominal/mean tr
46、ansmitter power“. This parameter is required because in many cases the nominal (rated) transmitter power (known for the user) is different from the mean transmitter power (required in the formula for the rms electric field strength calculation). After choosing the type of service, the nominal transm
47、itter power will be automatically multiplied by a suitable coefficient. Table B.1 contains the coefficients for the most commonly used types of radiocommunication services. Rec. ITU-T K.70 (2007)/Amd.5 (04/2016) 7 I.6 Library radiation patterns of the antenna systems In the folder “Library“, the fil
48、es containing radiation patterns for some typical antenna systems used in radiocommunication and broadcasting are collected. There are patterns for FM, TV VHF, TV UHF, GSM 900, GSM 1800, AM and radio relay link antennas. Of course, this library contains only the samples of possible configurations of
49、 antennas and antenna systems that are in use worldwide. It should be noted that each broadcasting antenna is individually designed and there are no two identical systems. However, the antennas included in the library represent typical solutions realized in many telecommunication systems. There is also a subfolder “User input templates“ containing “User_2D_Import_Radiation _Pattern.csv“ and “User_3D_Import _Radiation _Pattern.csv“ files, in a format which enables importing user data for any additional ante
