trans_dsp16_twiddle_factors.h File Reference

#include "dsp.h"

Macros
Twiddle factors table
#define	DSP16_N_TWIDDLE_FACTORS   1024
	This constant defines the size of the twiddle factors table we want to store in memory. i.e.: if we want to compute a 1024-point (or less) complex FFT, we will define this constant as follow: More...
#define	TWIDDLE_FACTORS_PREFIX_TAB
	This constant permits you to add attributes to the twiddle factors table. It is useful if you want to store the table into another memory for example. i.e.: More...

Variables
TWIDDLE_FACTORS_PREFIX_TAB dsp16_t	dsp16_twiddle_factors []
	This table has been generated using the following algorithm: More...
TWIDDLE_FACTORS_PREFIX_TAB dsp16_t	dsp16_twiddle_factors2 []
	This table has been generated using the following algorithm: More...

TWIDDLE_FACTORS_PREFIX_TAB dsp16_t dsp16_twiddle_factors[]

This table has been generated using the following algorithm:

for i=0:4:DSP16_N_TWIDDLE_FACTORS,
k = i/(DSP16_N_TWIDDLE_FACTORS*4);
w = exp(-2*PI*%i*k);
end;

It is a one dimensional array containing the real parts (even parts) and imaginary parts (odd parts) of the w value.

Referenced by dsp16_trans_complexfft(), dsp16_trans_complexifft_ex(), and dsp16_trans_realcomplexfft().

TWIDDLE_FACTORS_PREFIX_TAB dsp16_t dsp16_twiddle_factors2[]

This table has been generated using the following algorithm:

for i=0:4:DSP16_N_TWIDDLE_FACTORS-4,
k = i/(DSP16_N_TWIDDLE_FACTORS*4);
w2 = exp(-2*PI*%i*k*2);
w3 = exp(-2*PI*%i*k*3);
end;

It is a one dimensional array containing the real parts (4*i parts) and imaginary parts (4*i+1 parts) of the w2 value and the real parts (4*i+2 parts) and imaginary parts (4*i+3 parts) of the w3 value.

Referenced by dsp16_trans_complexfft(), dsp16_trans_complexifft_ex(), and dsp16_trans_realcomplexfft().