Portable Installation Suite
Thanks to the coding expertise of Christophe Marchand, author of the MeteorGIS software, it is now feasible to apply Geographic Information System (GIS) mapping to Meteor LRPT imagery. I'm grateful to Rob Bale, who has adapted my Meteor LRPT Suite to interface with MeteorGIS, and thus automatically create a range of Meteor images with geospacial correction.
For those interested in the minutiae of setting up such a system from scratch, I recommend consulting the relevent section of Happysat's guide: Setup Meteor M-N2/N2-2 with LRPT-Decoder.
To download the MeteorGIS-basic Suite
This, as its name infers, is a basic MeteorGIS setup, which is configured to run specifically from the C:/ drive of your computer. DON'T extract it into Window's Program Files folder - if you do, it won't work!: the zipfile MUST be unpacked directly to the C:/ drive of your computer.
When you unpack the zipfile, everything that's needed is contained in a master folder called simply Meteor: its component folders and files are illustrated in the diagram opposite.
The SDRSharp and Orbitron subfolders are the same as with the earlier suites. The image acquisition process is, as previously, initiated by running Orbitron, and selecting the SDRSharp driver from its opening screen. But as soon as M2_LRPT_Decoder starts, its output is redirected to the software within the MeteorGIS folder.
Meteor s-files are then saved in the S_file folder.
Before you start ...
There are several things that you have to do to make the setup fully operational.
• Your computer must be on-line to run MeteorGIS. This is because the first thing MeteorGIS does when it runs is to
• If you haven't used SDRsharp for Meteor reception before, run zadig to install the RTL drivers for your dongle. You can
• You will have to set the Tuner Correction (ppm) to precisely centre the frequency in SDR# for you own specific RTL dongle.
• The Meteor frequency is set at 137.1 MHz in both Orbitron and SDRSharp.
• You must enter your location coordinates in Orbitron's Location tab.
• In Orbitron, click the symbol to enter your Time Zone.
Once this is done, everything is set to go. All you need to do is run the file orbitron.exe from the 'Orbitron' folder, click the 'Rotor/Radio' tab at the foot of its display, and finally click the small button to the right of the 'Driver' window showing 'SDRsharp'. This will activate SDRsharp, and Meteor data will be processed automatically by MeteorGIS on every pass, under control of SDRsharp.
And of course, you must connect a 137 MHz APT antenna (turnstile, QFH etc) to your dongle in order to receive the Meteor signals. Your APT antenna for the NOAA satellites is ideal.
What to expect ...
• As soon as the Meteor satellite has risen high enough above your horizon, SDRsharp will burst into life and the
Meteor demodulator plugin will activate, soon to be followed by the appearance of the MeteorGIS screen display
stating: "Waiting for lock" and "Connected to Meteor Demodulator Plugin".
• Once the Meteor signal is strong enough, "locked" shows on SDRsharp's Meteor demodulator panel and
• You should now be seeing the three Meteor channel images building up in M2_LRPT_Decoder.
• When the Meteor pass ends, M2_LRPT_Decoder closes and disappears from the screen, and MeteorGIS starts
• Once MeteorGIS has completed its magic, it disappears from the screen, indicating that image processing is complete.
It is important to be patient and not interfere while all this processing takes place.
The basic MeteorGIS software suite provided is a good starter option, but MeteorGIS is capable of much more. Extra and enhanced features can be brought into play by editing the default.ini and thermal.ini files within the application folder. This is achieved by use of a file named MeteorGIS_Configurator.exe, which sits inside the MeteorGIS application folder.
When you first run Configurator (by double-clicking it), it displays a file-list box with two entries for you to select: the two '.ini' files mentioned above. Once you select an ini-file, you will be presented with options which include:
There are lots of modifications you can make, but be wary of changing too much at one go. I—and clearly many others before me—have made numerous alterations to MeteorGIS, only to discover that I ended up with a non-functioning system. So the advice is to make one change at a time and check it out by running MeteorGIS in manual mode (see next section).
After you have made changes to the .ini files using MeteorGIS_Configurator, you might have anticipated finding a Save button at the foot of the screen: I certainly did! But no such luck! You have to return to the top of the screen and confirm your edits using File/save on the top menu bar.
Running MeteorGIS in Manual Mode
There is a batch file in the MeteorGIS folder named Manual_M2_GIS.bat which allows you to manually reprocess the most recent Meteor pass. To do so, you must first of all delete all the existing images in the Finalimages folder. Running Manual_M2_GIS.bat (by double-clicking it) will reprocess the Meteor data and generate an updated set of geospatially processed images. Note that, if you don't first clear files from the Finalimages folder, no reprocessing will occur!
There are two types of overlay that can be applied to Meteor GIS images: what the author terms Watermarks and Shapes.
The Watermark is nothing of the sort: it is in fact an overlay showing information about the Meteor pass. A typical example appears opposite. There are options in the .ini files to change the colour, size and position of this overlay. This option is switched off in the MeteorGIS-basic suite.
The Shapes feature makes use of a set of 'shapefiles' present in the MeteorGIS folder to overlay 'shapes' over the modified Meteor images. The 'shapes' have the following effects:
The Shapes feature has a tab all to itself in MeteorGIS_Configurator.exe and takes the form of a slider-bar which you drag to set a number between 0 and 5 as appropriate for your needs.
Note that these operations are cumulative: you cannot, for example add a grid or placename markers without country boundaries and coastlines!
Filling in the blanks
Due to a malfunction aboard the Meteor M2 satellite—apparently caused by buffer overflow—the LRPT images almost always exhibit intrusive, broad dark bands every six minutes or so.
MeteorGIS does its best to 'cover up' these areas by intelligent processing. Although the repairs are obvious if you zoom in closely, generally, when viewing the satellite images as a whole, the process does a remarkably good job.
MeteorGIS first makes repairs to each of the three greyscale images derived from LRPT Decoder, then creates an RGB composite image (RGB125 or RGB123) from these. The appropriate geospacially modified images are subsequently created from these (you can see references to 'corrections' in the MeteorGIS panel displayed above).
If you prefer your Meteor images simply to be rectified in their original form (without the GIS effect), you can process this composite RGB125/RGB123 image (also to be found in the FinalImages folder, with the prefix 'comp') in SmoothMeteor, giving the bonus of removing any intrusive black bands.
To see a selection of MeteorGIS images illustrating the variety of formats