Here’s a very helpful guide on using GPU FFT with your raspberry pi, from Andrew Holme:
GPU_FFT is an FFT library for the Raspberry Pi which exploits the BCM2835 SoC V3D hardware to deliver ten times more data throughput than is possible on the 700 MHz ARM. Kernels are provided for all power-of-2 FFT lengths between 256 and 131,072 points inclusive.
I was wondering if my Homemade GPS Receiver‘s FFT-based signal acquisition could be accelerated using the Raspberry Pi’s BCM2835 GPU. Then, Raspberry Pi Foundation CEO Eben Upton attended the Radio Society of Great Britain (RSGB) Convention, where radio amateurs told him FFT performance of its 700 MHz ARM limited the Pi’s usefulness in Software Defined Radio (SDR) applications.
I decided to develop a general-purpose FFT library, GPU_FFT, using the quad processing units (QPUs) in the BCM2835 V3D block. As a Broadcom employee, I had access to inside information; but I had never worked on V3D. Fortunately, I received invaluable advice from several colleagues. Thanks to Eben, Dom, Tim, Gary and Dave.
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