1/8/2013. Not one, single technology, rather a convergence of several technologies Systems for:

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1 Tracking Technologies Priscilla ill Grantham, Esq. Sr. Research Counsel National Center for Justice and the Rule of Law Copyright 2012 Priscilla Grantham & National Center for Justice and the Rule of Law NCJRL. org 1 Special thanks: Don Mason Acting Director National Center for Justice and the Rule of Law 2 Location Tracking Not one, single technology, rather a convergence of several technologies Systems for: Tracking inventory, livestock, vehicles, or humans Delivering location-based services to wireless devices 3 1

2 Types of Devices Smartphones GPS Digital Cameras Beepers 4 Tracking Devices? 5 Secure Continuous Remote Alcohol Monitor SCRAM 6 2

3 Our Focus Today Cell phones Networks and how they work Cell site location information (CSLI) Beepers Global Positioning System (GPS) Digital Cameras 7 Processes Cellular network triangulation GPS trilateration Geotagging 8 From bricks to smartphones 9 3

4 Statistics Over 5.7 billion cell phones worldwide 327 million in US (103% of population) 1.6 billion smartphones sold in Most Towers Tri-directional

5 Cellular network Cellular Networks 15 5

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7 19 Cell Site Location Information Mobile switching centers may retain location information in call detail records at least for a period of time (e.g., 24 hours) Authorities can track subscriber s general movements by following sequence of towers contacted by the phone May also obtain last recorded location before signal or power lost 20 Cell Site Location Information Most useful location information comes from initiation or receipt of a call or text Call data record (CDR) kept for billing purposes Yields historical account of cell phone s locations Officers may also locate phone in real time while a call is in progress 21 7

8 Enhanced FCC mandate of 95% of phones Locate phone location within 300 meters Within 6 minutes 22 Smartphones GPS (discussed in next Section) 23 There s an App for that 24 8

9 Smartphones Therefore, cell phones contain lots of data: Messages Voic s s Pictures & Video Location, trip data Contacts However, some of this information may not be on the phone 25 Beepers 26 Beepers Requires tailing Antenna used to track radio signals Up to 5 miles Placed on car or package 1 x2 to 3 x5 Does not store information 27 9

10 Beepers Use beeps and/or lights to indicate: Direction (but not very well) Distance 28 GPS 29 GPS Global Positioning System Developed by US government for military purposes Cost unknown, but EU s competing system expected to cost around $25 billion Still operated by the military 30 10

11 GPS: three components 1. Satellites 32 Earth-orbiting solar-powered satellites Each knows its distance from the center of the Earth 2. Ground Stations 11 around the globe 3. Receivers Calculate their distance from satellite 31 GPS Satellites 32 GPS Ground Stations 33 11

12 GPS receivers 34 2-D Trilateration Involves a series of difficult calculations Instead of learning that, let s use pictures 35 2-D Trilateration Detroit 366 miles 36 12

13 2-D Trilateration Detroit 312 miles Richmond 37 2-D Trilateration Detroit Charleston 388 miles Richmond Nashville 38 3-D Trilateration 39 13

14 3-D Trilateration 40 3-D Trilateration 41 3-D Trilateration 42 14

15 3-D Trilateration 43 GPS Accuracy is limited by: Earth s atmosphere Weather generally has no effect But doesn t work underwater Structures, Terrain, Foliage Clock errors Gravitational effect on satellite orbits 44 GPS Generally, accurate to 15 meters Receivers use Differential GPS to calculate error Makes measurement accurate to 10 meters, but possibly up to 10 centimeters 45 15

16 Assisted GPS (A-GPS) Uses an assistance server to more rapidly or accurately obtain a location Can be used in lieu of a fully functional GPS receiver or can be used to enhance accuracy of a location If the GPS receiver has trouble determining a location, A-GPS can make a connection using cell network to send data 46 Assisted GPS (A-GPS) Many cell phones use A-GPS, cell site triangulation and other technology to determine location Other benefits Uses less battery power Less time to get a fix Better coverage System can be upgraded at network level 47 Assisted GPS (A-GPS) Satellites Phone Company s Receiver Cell Towers Smartphone A-GPS Server 48 16

17 GPS Data Data that may be located on the GPS receiver includes: Device information Deleted locations Owner information Last fix Waypoints Routes/Journeys Home location Track logs Points of interest (POI) Favorites 49 Digital Cameras Pictures and video Geotagging Especially in smartphones 50 Geotagging Adds latitude and longitude coordinates to pictures and video Stored in metadata; not visible in the image Usually derived from GPS Camera must have a built-in in GPS receiver Can also be used with text messages, social networking updates, and blog posts 51 17

18 Geotagging 52 Convergence 53 Presented by Priscilla Grantham Senior Research Counsel, NCJRL