GPS for Dummies.pdf - Engineering Surveyor

Chapter 4Grasping Important GPS ConceptsIn This Chapter Understanding GPS, maps, and coordinate systems Working with GPS and datums Setting GPS receiver waypoints Using routes Making the most of tracksIn Chapter 3, I provide you with a pretty good idea of what GlobalPositioning System (GPS) is and how it works. In addition to knowing aboutthe satellites, ground stations, and receivers, however, you should have agrasp of some important concepts before you start using a GPS receiver —things like coordinate systems, datums, waypoints, routes, and tracks.Even if you already own a GPS receiver and have used it for a while, this isstill a good chapter to skim through because some of these basic conceptsthat I discuss end up being overlooked in user manuals or can get a bit fuzzyif you don’t use your GPS receiver on a regular basis. Read on while I helpclarify some important terms and concepts (like datums and waypoints androutes) so you’ll be (pardon the pun) moving in the right direction.Linking GPS, Maps, andCoordinate SystemsSome people think that after they have a GPS receiver, they really don’t needa map, especially if the receiver has built-in mapping capabilities. This isn’tnecessarily true. GPS receivers are best used in conjunction with maps,whether those maps are paper or digital. Here are some of the reasons why: Detail: Most maps on handheld GPS receivers don’t offer the detail offull-size paper or digital maps, especially topographic maps and nauticalcharts.