Tom Fisher – Supervisor - A/Prof Andrew Dempster Assessor - Dr Jinho Choi Combining GPS and CDMA Cellular Network Measurements for Positioning

Cellular Network Positioning Definition Equipment and algorithms applied to CDMA cellular wireless telecommunications to determine geographic position, and in some cases the velocity and direction of travel of wireless devices. Source: Technology_Center

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning Stakeholders  Emergency Services (esp. US)  Communications Authorities  Mobile Phone Operators – E911 ( )  Mobile Phone Users

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning Benefits  Enhanced 911 (FCC 2000 Mandate)  Traffic Information  Location Based Billing  Enhanced Roadside Assistance  RF/Network Optimisation  Navigational Assistance  Personal Location

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning Current Standards and Previous Work  IS-801 (Positioning Standard)  IS-95 (CDMA Communications Standard)  Rappaport (Various Papers)  SNAP Laboratory Work  UWCC Mobile Positioning Study  FCC Phase II Automatic Location Identification

Combining GPS and CDMA Cellular Network Measurements for Positioning Positioning Concepts Concept of Positioning  GPS: Uses at least 3 satellites (4 th for time/DGPS)  Uses Trilateration to determine position  Uses timing signals to determine relative position Source:

Combining GPS and CDMA Cellular Network Measurements for Positioning Positioning Concepts GPS  Each satellite sends 2 signals:  Location of Satellite:  Timing signal (Pseudo-Random Code):  For the Receiver:  Transmit time:  Distance from Satellite:

Combining GPS and CDMA Cellular Network Measurements for Positioning Positioning Concepts GPS Source:  The receiver is somewhere on a sphere of radius  Intersection of 3 spheres leaves possible 2 locations  Impossible locations are ignored  Coordinates are now known 

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning Technology Approaches  Network-Based Approaches  Time Difference of Arrival (TDOA)  Angle of Arrival  Multipath Analysis  Receive Power  Handset-Based Approaches  GPS  Network-Assisted GPS  Advanced Forward Link Trilateration  Enhanced Observed Time Difference (E-OTD) Source: Caffery and Stüber: Subscriber location in CDMA Cellular Networks, 1998

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning Compatibility  Network-Based Approaches  Does not require air interface modifications  Requires additional base station equipment  Added system maintenance  Handset-Based Approaches  Requires air interface modifications (TIA PN-4589 and TR 45.1)  Requires handset upgrades/replacement  Added system maintenance

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning UWCC Study Findings  Universal Wireless Communications Consortium (UWCC)  Revenue from New Services  Location is High Value, Low Bandwidth Data  Location Powers the Wireless Web  Enriches Value Added Internet Content

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning Proposed Solution  2 Goals:  Minimal Network Changes / Maximum Compatibility  Greatest Accuracy  2-D solution  Explore hybrid Handset/Network solutions  Conform to Australian and International Standards  Make recommendations for Australian E-000

Combining GPS and CDMA Cellular Network Measurements for Positioning Cellular Network Positioning Proposed Solution  Combination Network-Based Solution  TDOA  Receive Power  Hybrid Network/Handset Solution  E-OTD  Investigate Practicality and User Impact

Combining GPS and CDMA Cellular Network Measurements for Positioning Thesis A Current Status Current Status  Literature Review Completed by Session 1  Binghao Li’s Test Data Collated and Processed  Thesis Part B Planned

Combining GPS and CDMA Cellular Network Measurements for Positioning Thesis B Planning Timeline  Schedule has thus far been Accurate  Resources Acquired  GPS Reference Books  TDOA Test Data

Questions