Which radix processors are being widely used in the dsps? Radix 4 or radix 8?

Hello Shamsher,

In C5515 Device :

 C55x CPU includes a tightly-coupled FFT hardware accelerator that communicates with the C55x CPU through the use coprocessor instructions and also a loosely coupled Low Power FFT Coprocessor.

The tightly coupled FFT Hardware Accelerator supports 8 to 1024-point (in power of 2) real and complex-valued FFT.

The loosely coupled Low Power FFT Coprocessor performs a 16 to 128-pt complex FFT, FIR filters, and filterbank implementations .  Implements in-place computation of 16-, 32-, 64-, and 128-point DIT FFT and IFFT.  Performs a radix-2 DIT FFT butterfly in two CPU cycles.

Also more information can be found in the below link  :

tms320c5515

Hope this helps.

Regards

 Vasanth

Thanks vasanth. Can you please help me to understand that what is a "fixed coefficient multipliers" in dsp processors? Can you also provide me a link which explains it in detail. Further, haveyou seen any processor which implements radix  8 fft ?

The details of the C55xx device FFT implementation can be found in the below link :

sprabb6b

Regards

 Vasanth