front-end-cal - RF front-end center frequency and sampling
rate calibration tool.
front-end-cal
-config_file=<path-to-configuration-file> [OPTION]...
front-end-cal is a calibration tool for some DVB-T
receivers based on the Taiwan's Realtek RTL2832U chipset, sold in form of
USB dongles that allow users to watch over-the-air DVB-T European broadcast
television on their personal computers, to be used as GNSS front-ends.
- Normally, those
devices send partially-decoded MPEG transport frames over the USB, but
exploiting an undocumented mode of operation of the demodulator chip, the
user is able to obtain raw I&Q samples, stream them through USB to a
personal computer and then use gnss-sdr, turning the DVB-T receiver
into a GNSS receiver and delivering position in real-time.
- The crystal oscillator that
ships with the RTL2832U family devices exhibits limited accuracy to be used
as a GNSS receiver front-end without previous calibration.
front-end-cal implements the algorithm proposed in [1], and it
requires Internet access since it retrieves Assisted GPS data from SUPL
servers.
- front-end-cal is able
to work with raw data files or, if there is computational power enough, in
real time with suitable radio frequency front-ends. The whole receiver is
defined in a single configuration file, and therefore users can define
theirs.