William F. Young. This work was sponsored by the Public Safety Communications Research Lab of NIST, under Dereck Orr, Program Manager.

Transcription

1 William F. Young Kate A. Remley, Christopher L. Holloway, Galen Koepke, Dennis Camell, John Ladbury Electromagnetics Division National Institute of Standards and Technology (NIST) U.S. Department of Commerce, Boulder Laboratories wfy, remley, phone: This work was sponsored by the Public Safety Communications Research Lab of NIST, under Dereck Orr, Program Manager.

2 ! Motivation and Background! Overview of Measurement Campaign! Example Results! How and Why are these Data Useful?! Resources Available

3 September 11, 2001 showed some significant shortcomings with our knowledge of RF propagation in emergency response environments. [1] Poor interoperability between radio systems. Inability to communicate with responders deep within structures Ineffective use of radio-transmitters buried in collapsed material (emergency beacons). NIST Public-Safety Research Lab (PSRL) efforts in RF propagation for emergency responders. Collect RF signal penetration data in large, complex structures. Detect and locate radio signals buried in collapsed structures. Develop lab-based test methods for standards development: Existing radios New wireless technology [1] Final Report for September 11, 2001 New York World Trade Center terrorist attack, Wireless Emergency Response Team (WERT), Oct

4 Large body of openliterature data Representative difficult responder radio environments: Office buildings Apartments Processing facilities Urban settings etc. Convention Center Refinery Apartments Office Building High-rise Office Building

5 ! Narrowband Continuous recording of signal penetration throughout structure! 50 MHz, 150 MHz, 225 MHz, 450 MHz, 900 MHz, 1.8 GHz, 2.4 GHz, and 4.9 GHz! Wideband Signal penetration at select locations! Transform for time response (multipath)! 200 MHz to 1 GHz, 1 GHz to 18 GHz! Performance testing of wireless devices! Deploy RF PASS, wireless robots at same locations! Correlate performance to channel characteristics

6 N Narrowband measurements RX1 RX2!$#!%# '!#!&# Wideband measurements RX3 Transmitters carried through the building! Received power measured at three sites! Location is recorded! RF PASS measurements!"# '(#

7 D 10+ db drop entering the building (C) 20 db difference just outside the building (B) Weak signal at 10 th floor (E) F E C A B 40+ db decrease at 17 th floor (D) Very weak or no signal above 17 th floor! Receive site just outside building (A) Very weak or no signal in the basement (F)! Comparison of 4.9 GHz, 2.4 GHz, 900 MHz, and 750 MHz! Other receive sites provide similar results

8 5 th floor 10 th floor! A longer delay spread indicates a stronger multipath environment! Delay spread does not necessarily increase as the floor level increases 1 st floor

9 ! Communication system modeling! Channel models for network simulations! Standards Development! Use field test data to develop and validate labbased test methods! Spectrum Planning! Concept of Operations Planning! radios, robots, PASS devices

10 ! Compare coverage and multipath behavior in different buildings Percentage of Measured Signals 6 db greater than noise floor 10 db greater than noise floor 15 db greater than noise floor percent RMS Delay Spread (ns) Convention Center 60-Story Office Apartment MHz 750 MHz Minimum Maximum Average

11 ! NIST TechNotes! W. F. Young, et al., Measurements to Support Public Safety Communications: Attenuation and Variability of 750 MHz Radio Wave Signals in Four Large Building Structures, NIST Technical Note 1552, August 2009.! C. L. Holloway, et al., Attenuation of Radio Wave Signals Coupled Into Twelve Large Building, NIST Technical Note 1545, May 2008.! K.A. Remley, et al., Measurements to Support Broadband Modulated-Signal Radio Transmissions for the Public-Safety Sector, NIST Technical Note 1546, Apr ! K.A. Remley, et al., NIST tests of the wireless environment in automobile manufacturing facilities, NIST Technical Note 1550, Oct ! W. F. Young, et al., Measurements and Models for the Wireless Channel in a Ground-Based Urban Setting in Two Public Safety Frequency Bands, NIST Technical Note 1557, to be published Spring, 2011.! Journal Articles! W.F. Young, et al., Radio Wave Signal Propagation Into Large Building Structures Part 1: CW Signal Attenuation and Variability, IEEE Transactions on Antennas and Propagation, Vol. 58, Issue 4, April, 2010, pp ! K. A. Remley, et al., Radio Wave Signal Propagation Into Large Building Structures Part 2: Characterization of Multipath, IEEE Transactions on Antennas and Propagation, Vol. 58, Issue 4, April, 2010, pp ! NIST Wireless Metrology! " Scroll down to: Wireless System Measurements for Industry and the Public Safety Sector

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