SM 5 BSZ - First FFT timing for a small system using PentiumIII (Coppermine) at 650MHz
(Dec 30 2000)
Sampling rate = 96kHz.
No of A/D channels = 1.
No of RF channels = 1.
Useful bandwidth 90 kHz.

The PentiumIII is much faster than required for a small system and therefore the data is collected at higher speed using a Delta44 audio board. The numbers in the tables give the relative speed of the different fft routines designed for use with in a small system using a single audio channel.



  SIZE = 65536  16 bit no window, bandwidth 0.73Hz
Vers   Name                            Time
 0     Approx. radix 2 DIF C          7.58%
 1     Approx. radix 2 DIF ASM        7.05%
 2        --------------
 3     Approx. radix 4 DIT C          4.88%


  SIZE = 32768  16 bit no window, bandwidth 1.46Hz
Vers   Name                            Time
 0     Approx. radix 2 DIF C          5.02%
 1     Approx. radix 2 DIF ASM        4.78%
 2     Split radix DIT C              5.62%
 3     Approx. radix 4 DIT C          3.87%


  SIZE = 4096  16 bit no window, bandwidth 11.7Hz
Vers   Name                            Time
 0     Approx. radix 2 DIF C          2.55%
 1     Approx. radix 2 DIF ASM        2.38%
 2     Split radix DIT C              2.49%
 3     Approx. radix 4 DIT C          2.36%

  SIZE = 65536  16 bit sin squared window, bandwidth 1.46Hz
Vers   Name                            Time
 0     Approx. radix 2 DIF C         14.74%
 1     Approx. radix 2 DIF ASM       13.42%
 2        --------------
 3     Approx. radix 4 DIT C          9.72%


  SIZE = 32768  16 bit sin squared window, bandwidth 2.9Hz
Vers   Name                            Time
 0     Approx. radix 2 DIF C         10.33%
 1     Approx. radix 2 DIF ASM        8.44%
 2     Split radix DIT C              8.71%
 3     Approx. radix 4 DIT C          7.60%

  SIZE = 4096  16 bit sin squared window, bandwidth 23Hz
Vers   Name                            Time
 0     Approx. radix 2 DIF C          4.84%
 1     Approx. radix 2 DIF ASM        4.44%
 2     Split radix DIT C              5.00%
 3     Approx. radix 4 DIT C          4.28%