References

A good high level introduction to the technical philosophy behind Centar's architecture can be found in the article "Rethinking the FFT" and "Non-Power-of-Two Designs Do Not Have to Be Difficult" (and the Introduction and Background in the Electronics paper in the list below):

Several more technical papers are available describing some of the FFT features:

• “Distributed-Memory-Based FFT Architecture and FPGA Implementations” J. Greg Nash, Electronics, 7 (7) 116, June 2018
• “Efficient Circuit Architecture and FPGA Implementation for LTE Single Carrier FDMA DFT,” latest circuit summary, to be presented at 2016 Int. System-on-Chip Conf., Seattle, WA,  Sept. 2016 (associated presentation).
• “High-Throughput Programmable Systolic Array FFT Architecture and FPGA Implementations,” latest circuit summary, to be presented at 2014 International Conference on Computing and Networking, Honolulu, HI, Feb. 2014 (associated presentation).
• “A New Class of High Performance FFTs” describes Centar’s first “demonstration” 16-bit 256-point and 1024-point FPGA circuit designs (associated presentation).
• “A High Performance Scalable FFT” and “An FFT for Wireless Protocols” are papers that focus on the FPGA circuit design of a 256-point FFT and its application to 4G wireless systems. (Corresponding presentations are here and here.)
• “ A High Performance Block Floating Point Systolic FFT Not Limited to Powers of Two ” and “Computationally Efficient Systolic Architecture for Computing the Discreet Fourier Transform” focuses on the algorithm derivation and architecture. In addition a PowerPoint presentation are available summarizing the architecture in more visual form.
• “Constraint Directed CAD Tool For Automatic Latency-Optimal Implementation of 1-D and 2-D Fourier Transforms” deals primarily with issues related to use of a CAD tool to automatically derive the base-4 systolic architecture

Datasheets

• Fixed-size, power-of-two, streaming FFT
• Variable-size, power-of-two, streaming FFT
• Variable-size, power-of-two, streaming FFT with LTE OFDM short and long cyclic prefix
• Non-power-of-two, non-streaming, fixed and variable-size FFT
• Non-power-of-two DFT for LTE SC-FCMA
• Floating-point streaming FFT (IEEE754)