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Impact of Power Line Telecommunication Systems on Radiocommunication Systems Operating in the LF, MF, HF and VHF Bands Below 80 Mhz

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Impact of Power Line Telecommunication Systems on Radiocommunication Systems Operating in the LF, MF, HF and VHF Bands Below 80 Mhz Report ITU-R SM.2158 (09/2009) Impact of power line telecommunication systems on radiocommunication systems operating in the LF, MF, HF and VHF bands below 80 MHz SM Series Spectrum management ii Rep. ITU-R SM.2158 Foreword The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the radio-frequency spectrum by all radiocommunication services, including satellite services, and carry out studies without limit of frequency range on the basis of which Recommendations are adopted. The regulatory and policy functions of the Radiocommunication Sector are performed by World and Regional Radiocommunication Conferences and Radiocommunication Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common Patent Policy for ITU-T/ITU-R/ISO/IEC referenced in Annex 1 of Resolution ITU-R 1. Forms to be used for the submission of patent statements and licensing declarations by patent holders are available from http://www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Patent Policy for ITU-T/ITU-R/ISO/IEC and the ITU-R patent information database can also be found. Series of ITU-R Reports (Also available online at http://www.itu.int/publ/R-REP/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broadcasting service (sound) BT Broadcasting service (television) F Fixed service M Mobile, radiodetermination, amateur and related satellite services P Radiowave propagation RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing and coordination between fixed-satellite and fixed service systems SM Spectrum management Note: This ITU-R Report was approved in English by the Study Group under the procedure detailed in Resolution ITU-R 1. Electronic Publication Geneva, 2010 © ITU 2010 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without written permission of ITU. Rep. ITU-R SM.2158 1 REPORT ITU-R SM.2158 Impact of power line telecommunication systems on radiocommunication systems operating in the LF, MF, HF and VHF bands below 80 MHz*, **, *** (Question ITU-R 221/1) (2009) TABLE OF CONTENTS Page 1 Introduction .................................................................................................................... 9 1.1 Data communication over electrical power lines................................................ 9 2 Characteristics of radio frequency emission from PLT Systems ................................... 10 2.1 Radiation sources in a PLT system..................................................................... 10 2.1.1 Differential-mode and common-mode currents................................... 10 2.1.2 Generation of the common-mode PLT current .................................... 11 2.1.3 Common-mode current launched at the PLT modem output port ....... 11 2.1.3.1 Electrical characteristics of in-house power lines as seen from an outlet..................................................................... 13 2.1.3.2 Impedances of in-house power lines measured at an outlet .................................................................................. 13 2.1.3.3 Imbalance of in-house power lines measured at an outlet. 14 2.1.4 Converted common-mode current ....................................................... 15 2.1.4.1 Converted common-mode current generated at the remote unbalanced element4 .............................................. 15 2.1.4.2 Folded-dipole antenna effect of the switch branch............ 17 2.1.4.3 Mode conversion at the switch branch .............................. 18 2.1.5 Leakage from the in-house power line to the service wires outside the house...................................................... 20 2.1.5.1 Optimistic data................................................................... 20 2.1.5.2 Pessimistic data.................................................................. 21 2.1.6 Shielding effectiveness of the exterior walls of a house...................... 22 * The Administration of Japan reserves its position on this Report, pending further contributions on specific issues to be submitted at the next meeting(s) of Working Party 1A. ** The Administration of Syrian Arab Republic reserves its position on this Report. *** See also Report ITU-R SM.2157. 2 Rep. ITU-R SM.2158 Page 3 Radio system characteristics, protection criteria, and impact of PLT systems on radiocommunication systems ......................................................................................... 22 3.1 Broadcasting ....................................................................................................... 22 3.1.1 General characteristics of analogue LF, MF and HF broadcasting...... 22 3.1.1.1 Bandwidth.......................................................................... 22 3.1.1.2 Receiver noise.................................................................... 22 3.1.1.3 Minimum usable field strength.......................................... 23 3.1.1.4 Protection ratios................................................................. 23 3.1.2 General characteristics of DRM digital LF, MF and HF broadcasting 24 3.1.2.1 DRM robustness modes..................................................... 24 3.1.2.2 Spectrum occupancy types ................................................ 24 3.1.2.3 Modulation and protection levels ...................................... 25 3.1.2.4 Receiver noise.................................................................... 25 3.1.2.5 Minimum usable field strength.......................................... 25 3.1.2.6 Required signal-to-noise ratios for DRM reception .......... 26 3.1.3 LF, MF, HF and VHF radio broadcasting frequency ranges ............... 27 3.1.4 Protection criteria and acceptable interference .................................... 27 3.1.4.1 Recommendation ITU-R BS.1786 and ITU-R BT.1786 – Criterion to assess the impact of interference to the terrestrial broadcasting service .......................................... 28 3.1.4.2 Recommendation ITU-R BS.560-4 – Radio-frequency protection ratios in LF, MF, and HF broadcasting ............ 28 3.1.4.3 Recommendation ITU-R BS.703 – Characteristics of AM sound broadcasting reference receivers for planning purposes............................................................................. 28 3.1.4.4 Report ITU-R BS.1058 – Minimum AF and RF signal- to-noise ratio required for broadcasting in band 7 (HF).... 28 3.1.4.5 Annex 2 to Recommendation ITU-R BS.1615 – Planning parameters for digital sound broadcasting at frequencies below 30 MHz – RF protection ratios for DSB (DRM system) at frequencies below 30 MHz .......... 28 3.1.4.6 Derivation of acceptable range of field strength incident from the wired telecommunication systems ...................... 29 3.1.4.7 Receiver noise level and acceptable interference level ..... 29 3.1.4.8 Equivalent field strength of receiver noise ........................ 30 3.1.4.9 External noise.................................................................... 31 3.1.4.10 Permissible interference field strength .............................. 31 3.1.4.11 Protection criteria for the broadcast service ...................... 32 Rep. ITU-R SM.2158 3 Page 3.2 Amateur and amateur satellite ............................................................................ 34 3.2.1 General characteristics......................................................................... 34 3.2.1.1 Operational characteristics................................................ 34 3.2.2 Amateur frequency allocations ............................................................ 35 3.2.3 The protection requirements of the HF amateur radio service............. 35 3.2.3.1 Fade margin and the 0.5 dB protection criterion of HF amateur radio ..................................................................... 35 3.2.3.2 The noise floor in amateur radio bands ............................. 36 3.2.3.3 Acceptable noise floor levels............................................. 36 3.3 Aeronautical mobile and Radionavigation ......................................................... 37 3.4 General protection criteria considerations HF fixed and land mobile................ 39 3.4.1 Protection criteria and protection requirement..................................... 39 3.4.1.1 Protection criteria.............................................................. 39 3.4.1.2 Protection requirement ...................................................... 40 3.4.2 A possible protection criteria ............................................................... 40 3.4.3 Automatic link establishment systems................................................. 40 3.5 Maritime mobile................................................................................................. 40 3.5.1 Background .......................................................................................... 40 3.5.2 Frequencies allocated for maritime communications .......................... 41 3.5.3 Receiver parameters for the maritime mobile service in MF and HF bands .................................................................................................... 43 3.6 Radiolocation...................................................................................................... 44 3.7 Fixed ..................................................................................................................
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