Open System Standards for Tightly Integrated GPS/PCS Systems: Issues and Trades

Raymond DiEsposti and Steven Saks

Abstract:	The Global Positioning System (GPS) has re-cently been recognized as a promising technol-ogy for integration with wireless communica-tions handsets [1]. By October 2001, the Federal Communications Commission (FCC) will require wireless carriers to locate emergency E-911 call-ers within 125 meters, 67 percent of the time. Technological advances such as low-cost, power-efficient GPS chipsets and improved sig-nal processing for low Signal-to-Noise Ratio (SNR) environments have made GPS a more practical and attractive solution to this FCC re-quirement. Beyond the E-911 function, Personal Communi-cation Service (PCS) wireless providers are also recognizing the benefit of offering GPS naviga-tion as a value added service to their subscribers. This Personal Navigation Service (PNS) capa-bility should increase demand for providing navigation related data over the PCS link. In ad-dition, the integration of the two technologies also allows a synergistic performance enhance-ment or functional aiding, similar to GPS/Inertial Navigation System (INS) integration. For exam-ple, GPS positioning and timing can aid in PCS allocation of power, frequency and time slot re-sources and billing, while PCS downlink data, such as initialization data and differential correc-tions, can greatly enhance GPS acquisition speed, low SNR performance, and navigation accuracy. Real-time data supplied through PCS systems could also make GPS differential sys-tems, such as those used for surveying, more capable and cost effective. To realize optimal synergy, a tight coupling of the two technologies is needed, where appropri-ate data and accurate timing information can be freely exchanged. Architectures and designs which capture these synergies may be needed in order for PNS to become a practical consumer product. In order to stimulate development of open system standards for integrated GPS and PCS services, the authors will discuss issues and trades associated with the definition of standard data and message formats for GPS and PCS in-terfaces (in the form of an open, non-proprietary Interface Control Document (ICD)) that enable synergistic operation. The intention is for this ICD to also support efficient PNS operation.
Published in:	Proceedings of the 1999 National Technical Meeting of The Institute of Navigation January 25 - 27, 1999 Catamaran Resort Hotel San Diego, CA
Pages:	733 - 739
Cite this article:	DiEsposti, Raymond, Saks, Steven, "Open System Standards for Tightly Integrated GPS/PCS Systems: Issues and Trades," Proceedings of the 1999 National Technical Meeting of The Institute of Navigation, San Diego, CA, January 1999, pp. 733-739.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In