James L Farrell, John W lavrakas
Addressing GPS user problems
While GPS offers a ubiquitous, precise, and reliable positioning and timing service to much of the world, in many cases this service falls short. Anyone who has walked into a building with a GPS receiver actively displaying a location is aware of the immediate effect of the …

Today, the civil positioning, navigation, and timing (PNT) community needs a clear and concise statement of PNT needs. This statement should incorporate all aspects of PNT services and all applications and modes of PNT use. With such a statement, providers of PNT technology and services will be better able to plan for, develop, and implement their PNT services. While I offer my thoughts on this need for the United States, the arguments…

Professor Laboratory of Communication Engineering, Tokyo University of Marine Science and Technology, Tokyo, Japan QZSS is a Japanese Satellite System to augment the performance of GPS positioning. It was expected to provide the services of positioning, communication, and broadcasting…