EMF compliance assessment of radio base stations DAVIDE

EMF compliance assessment of radio base stations DAVIDE COLOMBI, ERICSSON RESEARCH

outline › Overview of EMF RBS requirements and standards › EMF compliance testing of RBS products › Research topics › Realistic exposure › Conclusions ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 2

EMF COMPLIANCE OF RBS International standards providing guidance and requirements on assessment of EMF compliance of RBS Place on the market › ITU-T (Adopted mainly developing countries) – ITU-T K. 52 – ITU-T K. 61 – ITU-T K. 70 › IEC 62232 – 1 st ed. published 2012, currently in maintenance phase - Product compliance - Laboratory-based Put into service › CENELEC (Europe) – EN 50383/50384/50385 for place on the market of RBS – EN 50400/50401 for put into service of RBS › Some countries have adopted their own regulation ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 3 - Put into operation - “Site” compliance

place on the market assessments › Why? Provide information about EMF exposure to the user of the product › How? Determine compliance boundary (CB), i. e. area outside of which the EMF exposure is below the limit › By means of? Calculations or measurements of SAR / field strengths Antenna Ambient sources and scatterers are not considered ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 4 RBS

macro rbs › Field-strength simulations are typically used to assess compliance with reference levels – Accurate and cost-effective – RBS antennas are relatively easy to model – Excellent agreement with measurements Antenna models are based on the design of real RBS antennas ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 5

compliance boundary for macro rbs Frequency: 2100 MHz Gain: 18 d. Bi Dimension: 1314 x 155 x 70 mm ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 6

pico and micro rbs › Compliance distance from 10 to 100 cm › SAR measurements used for small standalone equipment – Power < 1 W only localized SAR (EN 50383) – Power > 1 W localized SAR + spatially averaged field strength › Whole-body SAR measurements standardization is ongoing ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 7 Available power 1 -10 W

research topics › Fast whole-body SAR measurements method surface scan propagation algorithm › MIMO antennas › mm wave communications prototype, 60 GHz ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 8

maximum vs realistic exposure RMS Downlink Power › EMF compliance testing of RBS is conducted assuming constant transmission at the maximum power (normalized to maximum) Network data collected for more than 5000 RBS in Sweden › The actual transmitted power may be significantly below the maximum RBS compliance assessments are not representative of the realistic exposure conditions ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 9

Effects of using arbitrary emf limits 1 antenna, WCDMA 2100 MHz, 80 watt output power ICNIRP limits 61 V/m compliance distance 6 m Belgium limits 3 V/m compliance distance 100 m ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 10

Conclusions › EMF compliance testing of RBS products is conducted before placing on the market and putting into service › Place on the market testing of RBS includes determining the compliance boundary – 1 m to 6 m in the main beam direction for macro RBS antenna – 10 cm to 100 cm for small cell RBS products › RBS compliance assessment is not representative of the realistic exposure condition ITU Workshop on Human Exposure to Electromagnetic Fields ( EMFs), Turin, Italy, 9 May 2013 | © Ericsson AB 2013 | Page 11