Google earth
1 / 39

Google Earth - PowerPoint PPT Presentation

  • Uploaded on

Google Earth. Applications for Ham Radio. Radioactive Networks Pty Ltd. Who Am I?. Darryl Smith, VK2TDS, B.E. Self Employed Positioning Consultant Expert on Wireless Systems. The Talk. Introduction to Google Earth Applications for Ham Radio Tracking Weather

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Google Earth' - PamelaLan

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Google earth l.jpg

Google Earth

Applications for Ham Radio

Radioactive Networks Pty Ltd

Who am i l.jpg
Who Am I?

  • Darryl Smith, VK2TDS, B.E.

  • Self Employed Positioning Consultant

  • Expert on Wireless Systems

The talk l.jpg
The Talk

  • Introduction to Google Earth

  • Applications for Ham Radio

    • Tracking

    • Weather

    • Path Calculations

    • GIS

  • File Format - KML

  • Implementing Applications

    • VB.NET

    • ASP.NET

Google earth licensing l.jpg
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

Applications for ham radio l.jpg
Applications for Ham Radio

  • APRS / Tracking

  • Weather

  • Path Calculations

  • GIS Applications

History l.jpg

  • 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

Example of user l.jpg
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

Aprs tracking l.jpg
APRS Tracking

  • APRS Tracking is possible in Google Earth.

  • I have been importing APRS data into my own server software very successfully.

Weather l.jpg

  • 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

Image import l.jpg
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

Path calculations l.jpg
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

Building applications l.jpg
Building Applications

  • Visual Basic


  • PHP

Google earth back end l.jpg
Google Earth Back End

  • KML, an XML variant is used to draw

  • KML is hierarchical

    • That is elements can be added at any point…

File format architecture l.jpg
File Format / Architecture

  • Essential Information :-

    • KML Tutorial


    • KML Specification


Place a line l.jpg
Place a line…

Inside a Placemark










Folders l.jpg


<name>My House</name>

. . .


Network link l.jpg
Network Link










Two types of interface l.jpg
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

Slide31 l.jpg

  • 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.

Example of a use of view based output l.jpg
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

Building applications a simple kml file l.jpg
Building Applications A Simple KML File



<name>Server Name</name>





Building applications vb net l.jpg
Building Applications – VB.NET

Dim XTW as new XMLTextWriter (Filename, Nothing)


xtw.WriteElementString(“description”, “Description Text”)

xtw.WriteElementString("name", “Server name”)


Xtw.WriteElementString(“coordinates”, “151,-34,0”)

Xtw.WriteEndElement ‘point

Xtw.WriteEndElement ‘Placemark



Building applications asp net l.jpg
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)


"inline; filename=ge.kml")

.Write("<?xml version=“1.0” ?>” & vbCrLf)

line=“kml xlms=“” >”

.Write (line & vbCrLf)

.WriteFile(“filename.kml" & vbCrLf)

.Write("</kml>" & vbCrLf)

End with

End Sub

Building applications php 1 l.jpg
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 = '<Placemark>';

  • $response .= '<description>Generates a random placemark on each call to the server</description>';

Building applications php 2 l.jpg
Building Applications – PHP - 2

  • $response .= '<name>Random KML server</name>';

  • $response .= '<visibility>1</visibility>';

  • $response .= '<Point>';

  • $response .= "<coordinates>$lon,$lat,0</coordinates>";

  • $response .= '</Point>';

  • $response .= '</Placemark>';

  • echo $response; ?>

Slide38 l.jpg

  • $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];