GUPPI raw files are often used in radioastronomy/SETI to store the channelized IQ samples output by a polyphase filterbank. This is the typical IQ (voltage mode, in radioastronomy terms) output for many modern telescopes, since they use a polyphase filterbank as part of their DSP, so raw ADC samples are often not available.
gr-guppi contains a GUPPI File Sink block that can write GUPPI files. A GUPPI File Source block able to read GUPPI files might be added in the future.
gr-guppi requires GNU Radio 3.10. It can be built from source and installed as any other GNU Radio out-of-tree module:
mkdir build
cd build
cmake ..
make
sudo make install
sudo ldconfig
An example flowgraph showing how to build a polyphase filterbank that supplies
data to a GUPPI File Sink block is given in the examples folder. This
flowgraph generates a signal that consists of a chirp sweeping the central
channels plus AWGN, passes the signal through a polyphase filterbank such as the
one used in telescopes, and writes the results to a GUPPI file.
The output GUPPI file can then be processed by typical radioastronomy tools such
as rawspec and watutil from
blimpy. After running the example
flowgraph for some time, run the following to view the spectrum and waterfall of
the GUPPI file.
rawspec -j -f 64 -t 100 guppi_sink_example
watutil -p ank guppi_sink_example.rawspec.0000.h5