Where should a retail business occur or locate within a region? What would that trade area look like? Should a retail expansion occur and how would that affect sales of other nearby existing locations? Would a new retail location have the right demographic or socio-economic customer base to be profitable? These are important questions for retailers to consider. Within the evolving landscape of GIS, there is more geospatial data than ever before about the potential customer. In retail, the application of maps and mapping technology is growing to include commercial real estate, logistics, and marketing to name a few. There has been an increased momentum across commercial applications for geospatial technologies delivered in an easy to comprehend format for a variety of end users.
A global navigation satellite system (GNSS), composed of user receivers, satellites, and ground control stations, is designed to provide accurate positions in 3-dimensional space. The Global Positioning System (GPS) is one of four GNSS freely available today. The fundamental GNSS approach is widely used today in cellphones, automobiles, autonomous vehicles, uncrewed aerial vehicles, and even as tagged luggage or bicycles. Significant improvements in the GNSS approach is available to the educated mapping scientist with an appropriate GNSS receiver/antenna, the appropriate environmental context, and processing of the satellite signals. This chapter provides the reader the fundamental concepts involved in the GNSS approach. With such knowledge the reader can make informed decisions about receivers, their use in the environment, and processing approaches for their unique applications.