Matlab scripts according to my project on transmitter localization with time-difference-of-arrival (TDOA).
http://www.panoradio-sdr.de/tdoa-transmitter-localization-with-rtl-sdrs/
Presentation at the Software Defined Radio Academy, 2017
The matlab scripts are in an experimental state (though fully operational) and provided "as they are".
Three recordings from (the three) receivers done with the librtlsdr-2freq (modified librtlsdr for 2 frequency operation). First frequency is the reference transmitter, second frequency is the measurement frequency (required length: 3.6e6 (i.e. 1.2e6 samples per frequency), 2 Msps sampling rate).
- Delay analysis of reference signal to synchronize the receptions
- Delay analysis of measurement signal to measure the TDOAs
- Available Options: bandwidth filtering, correlation smoothing, correlation type switching, signal interpolation
- Mulitlateration calculations for localization
A html/javascript file with a map showing the receivers, the hyperbolas and the most likely position of the transmitter. Note, that the earth's surface is approximated by a plane (cartesian grid). The geodetic reference point is near the city of Kaiserslautern, Germany.