Geolocation accuracy requirements for E911 FCC MO&O 97-402, “Revision of the Commission Rules To Ensure Compatibility with Enhanced 911 Emergency Calling Systems” FCC 11-107, Third Report and Order, Second Further Notice of Proposed Rulemaking and Notice of Proposed Rulemaking

1. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 1
Geolocation Technologies Suitable to Meet
Regulatory Requirements for TV White Spaces
Name Company Address Phone email
Gerald Chouinard
Communications
Research Centre,
Canada
3701 Carling Ave.
Ottawa, Ontario
Canada K2H 8S2
(613) 998-2500 gerald.chouinard@crc.ca
Russ Markovsky InvisiTrack, Inc. (410) 991-8529 rmark@invisitrack.com
Authors:
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Abstract
This tutorial is to be presented during the IEEE 802 Plenary session on July 2011 in San Francisco. It gives
an introduction to the accuracy requirements for geolocation in TV White Space and an overview of
geolocation techniques that can be used for this purpose.

2. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 2
Geolocation technologies suitable to meet
Regulatory Requirements for TV White Spaces
FCC 10-174 Second Memorandum Opinion and Order
23 September 2010
15.711 (b) Geo-location and database access requirements. (Page 65)
(1) The geographic coordinates of a fixed TVBD shall be determined to an accuracy of +/- 50 meters
by either an incorporated geo-location capability or a professional installer. In the case of
professional installation, the party who registers the fixed TVBD in the database will be
responsible for assuring the accuracy of the entered coordinates. The geographic coordinates of a
fixed TVBD shall be determined at the time of installation and first activation from a power-off
condition, and this information may be stored internally in the TVBD.
(2) A Mode II personal/portable device shall incorporate a geo-location capability to determine its
geographic coordinates to an accuracy of +/- 50 meters. A Mode II device must also re-establish its
position each time it is activated from a power-off condition and use its geo-location capability to
check its location at least once every 60 seconds while in operation, except while in sleep mode,
i.e., in a mode in which the device is inactive but is not powered-down.
(3) …
(4) All geographic coordinates shall be referenced to the North American Datum of 1983 (NAD 83).

3. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 3
Geolocation accuracy requirements for E911
Network-based geolocation technology
(Triangulating the caller’s wireless signal in
relation to nearby cell sites)
• 100 m accuracy 67% of the 911 calls (probability
that the location would be within 100 m radius of
the CPE actual location).
• 300 m accuracy 95% of the 911 calls.
Handset-based geolocation technology:
(GPS or similar technology installed in the
caller’s handset)
• 50 m accuracy 67% of the 911 calls.
• 100 m accuracy 95% of the 911 calls.
FCC E911 phase 2
accuracy requirements
by Sept 11, 2012.
To be sunset in 2019.
FCC MO&O 97-402, “Revision of the Commission Rules To Ensure
Compatibility with Enhanced 911 Emergency Calling Systems”
FCC 11-107, Third Report and Order, Second Further Notice of
Proposed Rulemaking and Notice of Proposed Rulemaking

4. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 4
Geolocation accuracy vs fine ranging accuracy
• For a given geolocation error, the ranging error has to be smaller because
geolocation methods/ techniques can be subject to location geometry degradation.
Good Geometry
Bad Geometry
Trilateration
Triangulation
Assuming that the geometry degradation amplification is 2X (on average),
the required ranging accuracy is +/- 25 meters.
• In addition, the network device electronics propagation delays (residual delay) accuracy is
assumend to be +/- 30 ns. This results in +/- 10 meters ranging error
 In 802.22, this residual delay needs to be measured by the manufacturer with an accuracy of
at least +/-30 ns (IEEE Std 802.22-2011, subclause 7.7.7.3.4.10.)
• Thus the required fine ranging accuracy needs to be +/- 15 meters

5. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 5
Coarse ranging: use and limitations
• Ranging is used in communication systems to:
– Adjust the frequency of the CPE transmitted signal
– Adjust the timing of the CPE transmitted signal
– Adjust the signal transmission power for proper reception
– Signal the modulation and FEC to be used for operation
• Ranging can also be used for a rough estimate of the
signal flight time. However, the accuracy is limited,
at best, to the signal sampling period:
Base
Station
CPE
Customer
Premise
Equipment
T1= time of transmission
T4= time of reception
T2= time of reception
T3= time of transmission
Signal flight time= 1/2 * ((T4 - T1) - (T3 - T2))

6. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 6
Satellite-based geo-positioning
• Global Positioning System (GPS)
– provides location and time information
– needs unobstructed line-of-sight (outdoor)
– need time to lock to at least 3 satellites
• Differential Global Positioning System (DGPS)
– is an enhancement to GPS that uses a network of fixed, ground-
based reference stations to broadcast the difference between the
positions indicated by GPS and the known fixed positions.
• Assisted Global Positioning System (AGPS)
– can improve the startup performance, or time-to-first-fix (TTFF)
of a GPS positioning system. Uses terrestrial network resources to
locate and utilize the satellites faster and improve performance in
poor signal conditions. It is used extensively with GPS-capable
cellular phones (E911). It can allow for some indoor operation.
• Russian GLONASS system
• European Galileo system

7. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 7
Terrestrially-based geo-positioning
• Time-based
– Time of Arrival (TOA): terminal
is at intersection of three circles
centered at three BSs =>
trilateration (need synchronous
networks)
(outdoor)
– Time Difference of Arrival
(TDOA): terminal is at
intersection of three hyperbola for
which foci are at the three BSs =>
trilateration
(need synchronized BSs)
(outdoor)
– Larger signal bandwidth (e.g.,
UWB) results in higher resolution
ranging (indoor)

8. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 8
Terrestrially-based geo-positioning
• Angle-based
– Angle of Arrival (AOA):
smart and/or directional
antennas used at two BSs
=> triangulation (outdoor)
• Radio Map
– RSS Radio Map: Off-line
pre-calibration, on-line
matching of RSS at BSs to
identify location of
terminal (urban & indoor)
– Fingerprinting using local
multipath signature (urban
& indoor)

9. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 9
Terrestrially-based geo-positioning
• Other network-based positioning techniques
– Cell ID: BS and sector with which the terminal is communicating
– Observed Time Difference of Arrival (OTDOA) (for UMTS
networks)
– Uplink Time Difference of Arrival (U-TDOA): relies on multi-
laterations
• Non network-based positioning technique
– Round Trip Time (RTT): total round-trip time from a BS to a CPE
and back to the BS to determine the BS-CPE distance.
Triangulation on multiple RTT’s will allow geo-positioning
(outdoor & indoor).

10. doc.: IEEE 802.22-11/0079r00
Submission
July 2011
Gerald Chouinard, Russ Markvosky
Slide 10
References
1. Guolin Sun, Jie Chen, Wei Guo, and K.J.Ray Liu, “Signal Processing
Techniques in Network-Aided Positioning,” IEEE Signal Processing
Magazine, July 2005
2. Hui Liu, Houshang Darabi, Pat Banerjee and Jing Liu, “Survey of Wireless
Indoor Positioning Techniques and Systems,” IEEE Transactions on Systems,
Man, and Cybernetics – Part C: Applications and Reviews, Vol. 37, No. 6,
November 2007, pages 1067-1080
3. A. Roxin, J. Gaber, M. Wack, A. Nait-Sidi-Moh, IEEE Globecom
Workshops Washington, DC (2007)