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IQ Direction Power Spectrum

The IQ Direction Power Spectrum block adds an antenna rotation sync to the Spectra stream if the IsoLOG 3D DF antenna is running in chopper mode:

IQ Direction Power Spectrum Block

Left hand side Input:

  • IQ

Right hand side Output:

  • Spectra (with sync)
  • Detector (for debug)


If you are using the IsoLOG 3D DF antenna in chopper mode (the antenna segment switching time is below 20ms and could be as low as 1µs) it is impossible to know which antenna is switched since the data link to and from the IsoLOG 3D DF antenna is within the ms range while the IsoLOG 3D DF antenna could switch in the low µs range which is 1k- 10k faster.

To solve this problem we invented the IQ Direction Power Spectrum block which will analyse the IQ spectrum and will add an antenna sync information to it based on some advanced algorithm but you need to add some help e.g. the estimated Segment Duration and the Number of Segments (incl. trigger sector). At the end the complete antenna segment information is added to the Spectra data stream for a real-time DF calculation.

The block also converts the IQ data to Spectra by using our standard FFT processor:

Setting up the IQ Direction Power Spectrum block


A running block might look like attached screenshot:

Super fast DF with the help of an advanced antenna sync


The Detector output shows you if the sync is working correctly (check the red marked antenna segment):

DF Sync Verrification


A typical mission:

IQ Direction Power Spectrum Mission

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