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Author Topic: Short But In Depth TDoA Analysis  (Read 612 times)

Offline Josh

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Short But In Depth TDoA Analysis
« on: April 10, 2020, 2012 UTC »
 HF TDoA multilateration (1)
This blog post contains an analysis of TDoA multilateration applied to signal on 13413.4 kHz using a number of KiwiSDRs located in Europe.

For now the assumption used for making the KiwiSDR TDoA maps is that signals propagate with speed of light along the ground. Here we compare the measured delay differences with the ones obtained from this assumption.

All plots shown in this blog post are generated using octave/matlab .mat files available when using the updated KiwiSDR TDoA algorithm.

The cross-correlations for all combinations of used KiwiSDRs, normalized to have their maximum at unity, are shown below.
https://hcab14.blogspot.com/2020/04/hf-tdoa-multilateration-1.html
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Offline Josh

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Re: Short But In Depth TDoA Analysis
« Reply #1 on: May 03, 2020, 1759 UTC »
 HF TDoA multilateration (2)
This is an update to the last blog post where propagation delays from VOACAP are used in addition to great-circle-derived propagation delays.

As VOACAP provides a number of propagation modes (MODE=25) the mode which is most close to the measured time difference is used.
https://hcab14.blogspot.com/2020/04/hf-tdoa-multilateration-2.html
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Offline Teotwaki

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Re: Short But In Depth TDoA Analysis
« Reply #2 on: May 05, 2021, 0358 UTC »
That is an excellent blog. It will take me forever to get caught up. I just ran across it today due to my laziness in getting around to learning about the TDOA function in the SDRs   ;D
Jim
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76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half