1. Google Earth Applications for Ham Radio Radioactive Networks Pty Ltd Darryl@radio-active.net.au

2. Who Am I? Darryl Smith, VK2TDS, B.E. Self Employed Positioning Consultant Expert on Wireless Systems

3. The Talk Introduction to Google Earth Applications for Ham Radio –Tracking –Weather –Path Calculations –GIS File Format - KML Implementing Applications –VB.NET –ASP.NET

4. Introduction to Google Earth

5. Google Earth - Licensing Free to Non-Commercial Uses $20/Year upgrade for GPS functionality, and route editing $400/Year Commercial per seat –Movie Making - $200/Year –Premium Printing - $200/Year –GIS Data Import - $200/Year –Traffic Counts Data - $200/Year –Shopping Centre Data - $200/Year Server Licensable Separately

6. Applications for Ham Radio APRS / Tracking Weather Path Calculations GIS Applications

7. History Originally released as Keyhole Viewer by ‘Keyhole’ Most of the functionality was there in 2002, but Hardware and Networks were still lacking Google purchased Keyhole in 2004, about the time of the DCC

8. Example of User Beyond Blue – a suicide prevention group for farmers in the Australian Bush organized a drive of vintage tractors through the Simpson Desert They wanted to get community involvement so they set up a Google Earth feed showing their current position

11. Fergy 8

12. APRS Tracking APRS Tracking is possible in Google Earth. I have been importing APRS data into my own server software very successfully.

17. Weather Importing Weather Data into Google Earth from CWOP is fairly straightforward Vectors can be added for wind direction and velocity Graphics can show the rainfall Icons can be used for Temperature Graphs can be used to show trends Text Boxes can be used to provide all data

18. Image Import Overlays can be loaded periodically, such as with weather radar data These images can refresh automatically periodically Custom datasets can also be used

19. New Orleans – Post Katrina

21. St Catherines Island

22. Path Calculations Paths can be drawn on the map. These can be locked to the ground, or at a height. This can be done to model antenna paths. Without extra software it cannot do fresnel zones

24. Building Applications Visual Basic ASP.NET PHP

25. Google Earth Back End KML, an XML variant is used to draw KML is hierarchical –That is elements can be added at any point…

26. File Format / Architecture Essential Information :- –KML Tutorial http://www.keyhole.com/kml/kml_tut.html –KML Specification http://www.keyhole.com/kml/kml_doc.html

27. Place a line… Inside a Placemark absolute -112.2550785337791,36.07954952145647,2357 -112.2549277039738,36.08117083492122,2357 -112.2552505069063,36.08260761307279,2357 -112.2564540158376,36.08395660588506,2357

28. Folders My House...

29. Network Link 0 121 //myServer/Googleearth/example.kml 1 TestNetworkLink

30. Two Types of Interface Standard and ‘View’ based –Standard outputs data regardless of zoom level, area of display etc. –‘View’ sends the extents of the view to the server whenever the data is downloaded. View allows only appropriate data to be sent

31. KML can point to a service. So if you pan around a map, when you stop, the service is asked to return a relevant KML file. It might, for example, take the bounding box of the area on screen and reach into a database to draw up data for that geography and place it on top of Google Earth.

32. Example of a use of View Based output Take the example of using GoogleEarth to display Weather Data. Using the extents data you can determine the ZOOM level. You can then send the NOAA Weather station data when zoomed out Then as you zoom in CWOP stations are also displayed

33. Building Applications A Simple KML File Description Server Name 151,-34,0

34. Building Applications – VB.NET Dim XTW as new XMLTextWriter (Filename, Nothing) xtw.WriteStartElement("Placemark") xtw.WriteElementString(“description”, “Description Text”) xtw.WriteElementString("name", “Server name”) Xtw.WriteStartElement(“point”) Xtw.WriteElementString(“coordinates”, “151,-34,0”) Xtw.WriteEndElement ‘point Xtw.WriteEndElement ‘Placemark Xtw.flush Xtw.close

35. Building Applications – ASP.NET Private Sub Page_Load () Handles MyBase.Load With Page.Response.Clear();.CacheControl = "no-cache“;.Expires = -1.AddHeader("Pragma", "no-cache" & vbCrLf).AppendHeader("content-disposition", "inline; filename=ge.kml").Write(" ” & vbCrLf) line=“kml xlms=“http://earth.google.com/kml/2.0” >”.Write (line & vbCrLf).WriteFile(“filename.kml" & vbCrLf).Write(" " & vbCrLf) End with End Sub

36. Building Applications – PHP - 1 <?php $lat_int = rand(-90, 90); $lat_dec = rand(0, 1000000000); $lon_int = rand(-180, 180); $lon_dec = rand(0, 1000000000); $lat = $lat_int.'.'.$lat_dec; $lon = $lon_int.'.'.$lon_dec; $response = ' '; $response.= ' Generates a random placemark on each call to the server ';

37. Building Applications – PHP - 2 $response.= ' Random KML server '; $response.= ' 1 '; $response.= ' '; $response.= " $lon,$lat,0 "; $response.= ' '; echo $response; ?>

38. $coords = preg_split('/,|\s/', $BOX); $bl_lon = $coords[0]; $bl_lat = $coords[1]; $tr_lon = $coords[2]; $tr_lat = $coords[3]; // calculate the approx center $userlon = (($coords[2] - $coords[0])/2) + $coords[0]; $userlat = (($coords[3] - $coords[1])/2) + $coords[1];

39. Questions…