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IQ High Prec Power Spectrum

The IQ High Prec Power Spectrum block converts I/Q data via DOUBLE PRECISION real-time FFT to SPECTRA:

IQ High Prec Power Spectrum Block

Left hand side Input:

  • IQ

Right hand side Output:

  • Spectra


The IQ High Prec Power Spectrum converts I/Q data in real-time to SPECTRA using an highly optimized double precision 64Bit FFT algorithm. Using SPECTRA instead of I/Q highly reduces the CPU load needed to later on display and/or process the spectrum data.

The FFT Size can be adjusted from 16 to 268 Million (depending on the DSP Memory Model setting which you can adjust under Extras -> Configuration -> Performance -> DSP Memory Model).

Please note that pushing the FFT size to the limit will need a lot of processing time (and power) and lots of CPU memory!

Some examples for the FFT calculation speed on a regular Intel i7-7820HQ processor :

  • A 2 Million FFT needs around 1 s (@50% FFT overlap)
  • A 16 Million FFT needs around 8 s (@50% FFT overlap)
  • A 64 Million FFT needs around 35 s (@50% FFT overlap)
  • A 268 Million FFT needs around 135 s (@50% FFT overlap)

The FFT Overlapping is fully adjustable (up to 99,9%).

The following FFT Windowing functions are available:

  • Hamming
  • Hann
  • Uniform
  • Blackmann
  • Blackmann Harris
  • Blackmann Harris 7
  • Flat Top

IQ High Prec Power Spectrum Settings


A Screenshot comparing the regular 32Bit IQ Power Spectrum (left hand) and the 64Bit IQ High Prec Power Spectrum (right hand):

IQ High Prec Power Spectrum Block in Action


Typical Mission:

IQ Power Spectrum Typical Mission

File Reader to Double Precision FFT

IQ File to Double Precision FFT