Howtosignalprocessing
- Does FFT have to be power of 2?
- Are FFTs limited to sizes that are powers of 2?
- What are the two types of FFT?
- How many times faster is an FFT than a DFT for a block size of 256 samples?
Does FFT have to be power of 2?
Sure, you can use a radix-2 FFT to compute FFTs for lengths not a power of 2 (but it is not as efficient as using methods specifically tailored to the factors of the sequence length).
Are FFTs limited to sizes that are powers of 2?
1.6 Are FFTs limited to sizes that are powers of 2? No. The most common and familiar FFTs are “radix 2”. However, other radices are sometimes used, which are usually small numbers less than 10.
What are the two types of FFT?
These are called the radix-2 and mixed-radix cases, respectively (and other variants such as the split-radix FFT have their own names as well).
How many times faster is an FFT than a DFT for a block size of 256 samples?
This means FFT is 32 times faster than DFT.
