doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 1 Geolocation Technologies Suitable to Meet Regulatory Requirements for TV White Spaces Authors: Notice: This document has been prepared to assist IEEE It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEEs name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEEs sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair Carl R. Stevenson as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE Working Group. If you have questions, contact the IEEE Patent Committee Administrator at.http://standards.ieee.org/guides/bylaws/sb-bylaws.pdfCarl R. 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. doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 2 Geolocation technologies suitable to meet Regulatory Requirements for TV White Spaces FCC Second Memorandum Opinion and Order 23 September (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). doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 3 Geolocation accuracy requirements for E911 Network-based geolocation technology (Triangulating the callers 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 callers 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, To be sunset in FCC MO&O , Revision of the Commission Rules To Ensure Compatibility with Enhanced 911 Emergency Calling Systems FCC , Third Report and Order, Second Further Notice of Proposed Rulemaking and Notice of Proposed Rulemaking doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 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 , this residual delay needs to be measured by the manufacturer with an accuracy of at least +/-30 ns (IEEE Std , subclause ) Thus the required fine ranging accuracy needs to be +/- 15 meters doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 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)) doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 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 doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 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 ) doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 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) doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 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 RTTs will allow geo-positioning (outdoor & indoor). doc.: IEEE /0079r00 Submission July 2011 Gerald Chouinard, Russ MarkvoskySlide 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 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 A. Roxin, J. Gaber, M. Wack, A. Nait-Sidi-Moh, IEEE Globecom Workshops Washington, DC (2007)