SM 5 BSZ - First FFT timing for a medium system using Pentium Pro at 200MHz
(Dec 30 2000)
Sampling rate = 44.1kHz.
No of A/D channels = 2.
No of RF channels = 2.
Useful bandwidth 2*20 kHz.

Typical operation for first fft is SIZE=2048 in case second fft is enabled. The timings below indicate Pentium Pro at 200MHz will be fast enough for that. Without second fft Pentium Pro should run with 8192 or 16384 for the first fft for this configuration.



  SIZE = 4096  16 bit sin squared window, bandwidth 10.77Hz
Vers   Name                             Time
 0     Approx. radix 2 DIF C           13.63%



  SIZE = 8192  16 bit sin squared window, bandwidth 5.38Hz
Vers   Name                             Time
 0     Approx. radix 2 DIF C            16.1%
 1     Approx. radix 2 DIF ASM          13.5%
 2     Split radix DIT C                21.5%
 3     Twin approx. radix 4 DIT C       13.1%
 4     Approx. radix 4 DIT C            15.98%


  SIZE = 16384 16 bit sin squared window, bandwidth 2.69Hz
Vers   Name                             Time
 0     Approx. radix 2 DIF C            24.5%
 1     Approx. radix 2 DIF ASM          19.7%
 2     Split radix DIT C                26.3%
 3     Twin approx. radix 4 DIT C       15.2%
 4     Approx. radix 4 DIT C            18.5%