See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/267479961 Communication Systems in Aircraft with IEEE 802.11ac UNIVERSITY OF ROSTOCK RESEARCH GROUP COMPUTER ARCHITECTURE BOOK · OCTOBER 2014 READS 102 8 AUTHORS, INCLUDING: Djamshid Tavangarian University of Rostock 198 PUBLICATIONS 455 CITATIONS SEE PROFILE Daniel Versick University of Rostock 20 PUBLICATIONS 28 CITATIONS SEE PROFILE Ursula van Rienen University of Rostock 227 PUBLICATIONS 889 CITATIONS SEE PROFILE Revathi Appali University of Rostock 10 PUBLICATIONS 48 CITATIONS SEE PROFILE Available from: Djamshid Tavangarian Retrieved on: 05 February 2016
Communication Systems in Aircraft with IEEE 802.11ac
EMF Effects of IEEE 802.11ac for In-‐Flight Communication Systems
Oktober 2014
UNIVERSITY OF ROSTOCK RESEARCH GROUP COMPUTER ARCHITECTURE
University of Rostock, Research Group Computer Architecture / Oktober 2014
Communication Systems in Aircraft with IEEE 802.11ac
EMF Effects of IEEE 802.11ac for In-‐Flight Communication Systems
Imprint
Editor:
Prof. Dr.-Ing. habil. Djamshid Tavangarian (University of Rostock) Authors:
University of Rostock, Research Group Computer Architecture
Prof. Dr.-Ing. habil. Djamshid Tavangarian Dr.-Ing. Daniel Versick Dipl.-Inf. Alexander Gladisch
brown-iposs GmbH
Dr. rer. nat. Bernd Schröder Dipl.-Ing. Markus Fischer, M.Sc. CE Karsten Schmeling, B.Sc. EE
University of Rostock, Chair of Theoretical Electrical Engineering
Prof. Dr. rer. nat. habil. Ursula van Rienen Dr.-Ing. Revathi Appali
Contact:
[email protected] University of Rostock Faculty of Computer Science and Electrical Engineering Institute of Computer Science Research Group Computer Architecture Joachim-Jungius-Straße 9 18059 Rostock Germany
University of Rostock, Research Group Computer Architecture / Oktober 2014
University of Rostock, Research Group Computer Architecture / Oktober 2014
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Table of Contents
1. Introduction ...................................................................................................... 8 1.1. Motivation of the Study ......................................................................... 8 1.2. Goals of the Study.................................................................................. 9
2. Comparison of Wi-Fi 802.11ac and its Predecessors..................................... 10 2.1. 802.11ac in the 802.11 Family............................................................. 10 2.2. Differences and Additions of Wi-Fi 802.11ac Compared to
802.11a/n ............................................................................................ 11 2.2.1. MIMO and MU-MIMO....................................................... 11 2.2.2. Beamforming....................................................................... 13 2.2.3. Mandatory 5 GHz Operation and Channel Bonding........... 14 2.2.4. Modulation and Coding Schemes (MCS) ........................... 15 2.2.5. Data Rates ........................................................................... 15
2.3. Future Development of 802.11ac and Wi-Fi Certification .................. 16 2.4. Operation Cases for 802.11ac .............................................................. 17 2.5. Summary .............................................................................................. 18
3. Limitations and Regulations related to 802.11ac and Consequences of new 802.11ac Features Regarding EMF ............................................................... 19
3.1. Radio Channels .................................................................................... 19 3.2. Transmission Power ............................................................................. 19 3.3. Exposure Limits ................................................................................... 21 3.4. Transmission Power of 802.11ac Devices in Damage Case ................ 22 3.5. 802.11ac MIMO Transmissions with more than 3 Spatial Streams..... 24 3.6. 802.11ac MU-MIMO ........................................................................... 24 3.7. Summary .............................................................................................. 25
4. Use Cases "Usage of 802.11ac in Aircraft" ................................................... 27 4.1. Use Cases "Notebook User" and "Personal Devices (PD)" ................. 27 4.2. Use Case "Mixed Devices (MD)" ........................................................ 28 4.3. Use Case "Mixed Devices, Apart Locations (MD-AL)"...................... 28 4.4. Use Case "2.4 GHz, Mixed Devices (MD-2.4GHz)"........................... 28
5. Test Set-up and Measurements ...................................................................... 29 5.1. Test Equipment .................................................................................... 29
5.1.1. Access Points and Clients ................................................... 29 5.1.2. Chipsets of the Used Access Points and Clients ................. 30 5.1.3. Restrictions.......................................................................... 31
5.3.1. Hard- and Software ............................................................. 32
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5.3.2. Restrictions.......................................................................... 33 5.4. Test Scenario Aircraft ("Real World")................................................. 33
5.4.1. Goal of Experiment ............................................................. 33 5.4.2. Site Survey (802.11ac Coverage Measurements)................ 33 5.4.3. Detection of Spectrum Utilization by Third Parties ............ 34 5.4.4. Testbed Configuration......................................................... 35 5.4.5. Test Cases............................................................................ 37 5.4.6. Measurement Results .......................................................... 39
5.5. Test Scenario Laboratory ("Controlled Environment") ....................... 42 5.5.1. Goal of the Experiments...................................................... 42 5.5.2. Testbed Description............................................................. 43 5.5.3. Test Cases............................................................................ 43 5.5.4. Results ................................................................................. 44
5.6. Application of measurements to extended scenarios ........................... 47 5.6.1. Coverage Prediction for other Aircraft Types..................... 47 5.6.2. Spatial EMF Distribution within Ad-hoc Networks............ 54
6. Human Health Effects of 802.11ac-related Electromagnetic Fields in Aircraft .................................................................................................................. 58
6.1. Analysis of Reports on EMF Regarding WLAN and Public Health.... 59 6.2. Analysis of Simulations Regarding EMF Produced by WLAN and
Public Health ...................................................................................... 62 6.3. Analysis of Measurement Results Regarding EMF and Exposure
Limits.................................................................................................. 64 6.4. Estimation of 802.11ac Related EMF Effects in Case of Failure
Operation ............................................................................................ 66 6.5. EMF Effects of Wi-Fi on the Human Body with Implanted
Medical Devices ................................................................................. 66 6.5.1. Passive Implanted Medical Devices.................................... 67 6.5.2. Active Implanted Medical Devices (AIMD)....................... 67
6.6. Summary and Closing Remarks........................................................... 71
7. Summary and Future Work ............................................................................ 73 7.1. Summary .............................................................................................. 73 7.2. Outlook and Future Work .................................................................... 74
9. List of Figures, Tables, and Abbreviations .................................................... 79 9.1. List of Figures ...................................................................................... 79 9.2. List of Tables........................................................................................ 81 9.3 List of Abbreviations............................................................................. 82
