1 2 SOURCES, MEASUREMENTS AND EXPOSURES ................................................................................ 4 2 2.1 Physical characteristics of electromagnetic fields ................................................................... 4 3 2.1.1 Electromagnetic fields and radiation .............................................................................. 4 4 2.1.2 Quantities and units ........................................................................................................ 4 5 2.1.2.1 Frequency and wavelength ................................................................................................. 4 6 2.1.2.2 Electromagnetic spectrum ................................................................................................... 5 7 2.1.2.3 Polarisation ......................................................................................................................... 6 8 2.1.2.4 Wave impedance ................................................................................................................. 7 9 2.1.2.5 Power density ...................................................................................................................... 7 10 2.1.2.6 Summary of quantities and units ......................................................................................... 7 11 2.1.3 Waveforms ...................................................................................................................... 7 12 2.1.3.1 Modulation .......................................................................................................................... 8 13 2.1.3.2 Bandwidth ........................................................................................................................... 9 14 2.1.3.3 Orthogonal Frequency Division Multiplexing (OFDM) ..................................................... 9 15 2.1.3.4 Pulsing (pulse modulation) ............................................................................................... 10 16 2.1.3.5 Multiple access methods ................................................................................................... 10 17 2.1.4 Field regions around sources ......................................................................................... 11 18 2.1.4.1 Far-field conditions and the inverse square law ................................................................ 11 19 2.1.4.2 Reactive near-field ............................................................................................................ 11 20 2.1.4.3 Radiating near-field .......................................................................................................... 12 21 2.1.5 Signal fading and multipath propagation ...................................................................... 13 22 2.2 Sources of exposure .............................................................................................................. 14 23 2.2.1 Natural sources .............................................................................................................. 15 24 2.2.1.1 Extraterrestrial sources...................................................................................................... 16 25 2.2.1.1 Terrestrial sources ............................................................................................................. 16 26 2.2.2 Environmental radio transmitters ................................................................................. 17 27 2.2.2.1 Radio and television broadcasting .................................................................................... 17 28 2.2.2.1.1 Long, medium and short-wave bands ............................................................................ 19 29 2.2.2.1.2 VHF and UHF Bands ..................................................................................................... 20 30 2.2.2.2 Cellular radio networks ..................................................................................................... 22 31 2.2.2.2.1 Technology generations ................................................................................................. 23 32 2.2.2.2.2 Mobile phone base stations ............................................................................................ 24 33 2.2.3 Domestic and indoor transmitters ................................................................................ 30 34 2.2.3.1 Wireless networks ............................................................................................................. 30 35 2.2.3.2 Smart meters ..................................................................................................................... 31 36 2.2.3.3 Microwave ovens .............................................................................................................. 32 37 2.2.4 Personal transmitters .................................................................................................... 32 38 2.2.4.1 Mobile phone handsets ..................................................................................................... 32 39 2.2.4.1.1 SAR values .................................................................................................................... 33 THIS IS A DRAFT DOCUMENT FOR PUBLIC CONSULTATION. PLEASE DO NOT QUOTE OR CITE. 1 40 2.2.4.1.2 Phones not making calls ................................................................................................. 35 41 2.2.4.1.3 Hands free kits and Bluetooth earpieces ........................................................................ 35 42 2.2.4.2 Terrestrial Trunked Radio (TETRA) ................................................................................ 36 43 2.2.4.3 Cordless phones ................................................................................................................ 36 44 2.2.4.4 Professional mobile radio ................................................................................................. 37 45 2.2.5 Industrial applications ................................................................................................... 37 46 2.2.5.1 Induction heating .............................................................................................................. 37 47 2.2.5.2 Dielectric heating .............................................................................................................. 38 48 2.2.6 Medical applications ...................................................................................................... 38 49 2.2.6.1 Magnetic resonance imaging ............................................................................................ 38 50 2.2.6.2 Diathermy ......................................................................................................................... 39 51 2.2.6.3 Surgical diathermy and RF ablation .................................................................................. 39 52 2.2.7 Security and article surveillance .................................................................................... 39 53 2.2.7.1 Electronic article surveillance ........................................................................................... 39 54 2.2.7.2 Body scanners ................................................................................................................... 39 55 2.2.7.3 Terahertz applications ....................................................................................................... 39 56 2.2.8 Radar and navigation ..................................................................................................... 39 57 2.2.8.1 Air traffic control radar ..................................................................................................... 40 58 2.2.8.2 Marine radar ...................................................................................................................... 40 59 2.2.8.3 Tracking radar ................................................................................................................... 40 60 2.2.8.4 Other radar systems .......................................................................................................... 40 61 2.2.8.5 Aircraft navigation (other than radar) ............................................................................... 40 62 2.3 Environmental personal exposure assessments ................................................................... 41 63 2.3.1 Measurement experience and approaches ................................................................... 41 64 2.3.1.1 Sensitivity aspects ............................................................................................................. 41 65 2.3.1.2 Population measurements ................................................................................................. 41 66 2.3.1.3 Micro-environmental measurements ................................................................................. 41 67 2.4 Exposure assessment ............................................................................................................ 42 68 2.4.1 Instrumentation............................................................................................................. 42 69 2.4.2 Protocols and standards ................................................................................................ 43 70 2.5 Exposure systems for laboratory studies .............................................................................