About a week ago I resumed working on GQRX – an experimental AM/FM/SSB software receiver powered by GNU Radio and using Qt for user interface. This time, however, I am not going to continue working on the Python receiver but create a new receiver from scratch written in C++. It will support Funcube Dongle and USRP/UHD devices.
I have wanted to implement a simple APT decoder for the NOAA weather satellites in GNU Radio for quite some time now, in particular since the USRP equipped with a TVRX or WBX daughterboard and a GNU Radio FM receiver can be an extremely good receiver for this purpose. Today I have spent some time looking at the details of decoding APT and actually ended up with a working prototype implemented using the GNU Radio Companion.
Up until now, users of Gpredict could click on a satellite in any view to make that satellite selected. For most views, selecting a satellite meant highlighting it and showing some additional info about it, or for the case of single satellite view to display the data for that satellite. In case you are not familiar with the terms module and view in Gpredict, a module is a logical object which groups a number of satellites and a ground station together, while views are the display widgets used to visualize the satellite data in different ways like map, list, polar plot, etc. A module can have any number of views laid out in a grid.