GPS in the lab

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how to transfer the data from the GPS unit and work them with the main GIS software packages The main software packages that we would recommend at this time are the following ESRI ArcInfo 9.0, 9.1, 9.2, 9.3 (the mostly used and basic GIS software package) Idrisi 16 Taiga an alternative to the above package also quite expensive Grass GIS which is free and sometimes said to be better than the two above but also hard to manoeuver Global Mapper 8, 9 or 10 this is a very useful program which can read and transform a great variety of files; also you can do a lot of useful maps with this GIS easy to use (in contrast with the three above) software package Google Earth 5.0 which is free - beautiful images of your mapping results overimposing the satelitary images, also available in 3D Garmin MapSource 3, 4, 5 or 6 this is compulsory for transferring the data from the GPS unit into the computer or from the computer to the GPS unit and is included within the Garmin GPS units packages Garmin RO.A.D. 2008 can be used both on the computer and on the Garmin GPS Map units; an advantage is that this map has a good database about the protected areas from the country The most simple way to transfer and visualize your work, either points or polygons which are the limits of the populations or habitats is the following. 1. Connect the GPS unit to the computer through the USB cable. 2. Start the Garmin MapSource program. Select transfer data from the GPS unit, then visualize the data on the left panel. In order to save only the data you are interested in at one time you should delete all the other tracks and waypoints. Then save the data as .gpx (GPS exchange files). You can also use the digitizer function within the program to make adjustments especially in regarding the polygons. 3. Start the program Global Mapper. Import the .gpx file that you saved. It would be very useful to have the SRTM (Shuttle Radar Topographical Mission) version 4 files of the region you are interested in, in the case of Romania these are srtm 41_03, 41_04, 42_03, 42_04 which can be dowloaded for free from here. With this program you cand edit the themes (points or polygons), measure their perimeter or area and visualize them against a SRTM DEM (digital elevation model - a 3D virtual surface of the relief forms). With the option 'generate contours' from these files you can easily generate the basic and most difficult to draw feature of a topographic map - the level curves. If you want to make a file readable and workable with ESRI ArcInfo you should save the themes as .shp file (shapefile) - notice that in this case three files actually will be provided, .shp, .dbx., and .dbf with the same name. All three are necessary for ArcInfo. If  you want to visualize your work in Google Earth in a splendid manner you can save the themes as a .kml / .kmz file which can immediately be opened and edited with the named free program (connection to the internet always necessary).