This free design demonstrates the usage of a fixed-point OptNgn FFT library element on an Opal Kelly XEM3010 module.
For a users guide see:
FFT Reference Design Users Guide
The reference design processes an input data stream of pairs of real numbers, representing a stream of complex numbers, in a C++ program running on a PC, ships that stream, over the Opal Kelly USB link, in a frame-by-frame way, to the XEM3010 board, processes each frame through the streaming OptNgn FFT residing on the target FPGA, and then ships the transformed frames back to the PC.
To download the code, see :
FFT Reference Design Code