i started to do a FFT from exact one sine wave with the XFFT(9.0). This works for the 32bit input signal, but for the 16bit input signal it seems not to work. By doing the FFT i would expect one peak in the frequency spectrum like i get in in the following picture:
XFFT settings:
- Architecture Choice -> Pipelined, Streaming I/O
- Transform Lenght -> 256
- Scaling Options -> Scaled
- Input Data Width -> 16 -> input signal from DDS 32bit
- Input Data Width -> 8 -> input signal from DDS 16bit
For generating a sine wave i use the DDS compiler at a Superious Free Dynamic Range of 96 dB and Frequency Resolution 100 Hz. The Phase Increment is in Streaming mode and set with a constant block to 4096. One sine wave is generated by 256 samples now (number_0 x2).
If the settings are switched now for a 16bit sine input signal the FFT works not like i would expect. Maybe anyone has an idea?
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Weevil
Hi all,
i started to do a FFT from exact one sine wave with the XFFT(9.0). This works for the 32bit input signal, but for the 16bit input signal it seems not to work. By doing the FFT i would expect one peak in the frequency spectrum like i get in in the following picture:
XFFT settings:
- Architecture Choice -> Pipelined, Streaming I/O
- Transform Lenght -> 256
- Scaling Options -> Scaled
- Input Data Width -> 16 -> input signal from DDS 32bit
- Input Data Width -> 8 -> input signal from DDS 16bit
For generating a sine wave i use the DDS compiler at a Superious Free Dynamic Range of 96 dB and Frequency Resolution 100 Hz. The Phase Increment is in Streaming mode and set with a constant block to 4096. One sine wave is generated by 256 samples now (number_0 x2).
If the settings are switched now for a 16bit sine input signal the FFT works not like i would expect. Maybe anyone has an idea?
Thanky for any response!
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