main.c

#include <stdlib.h>
#include <math.h>
#include <ti/dsplib/dsplib.h>

/* Global definitions */
//#define _LITTLE_ENDIAN
/* ×èñëî âèá³ðîê äëÿ ÿêèõ íåîáõ³äíî âèêîíàòè ØÏÔ*/
#define N 512

unsigned char brev[64] = {
    0x0, 0x20, 0x10, 0x30, 0x8, 0x28, 0x18, 0x38,
    0x4, 0x24, 0x14, 0x34, 0xc, 0x2c, 0x1c, 0x3c,
    0x2, 0x22, 0x12, 0x32, 0xa, 0x2a, 0x1a, 0x3a,
    0x6, 0x26, 0x16, 0x36, 0xe, 0x2e, 0x1e, 0x3e,
    0x1, 0x21, 0x11, 0x31, 0x9, 0x29, 0x19, 0x39,
    0x5, 0x25, 0x15, 0x35, 0xd, 0x2d, 0x1d, 0x3d,
    0x3, 0x23, 0x13, 0x33, 0xb, 0x2b, 0x1b, 0x3b,
    0x7, 0x27, 0x17, 0x37, 0xf, 0x2f, 0x1f, 0x3f
};

/* âèð³âíþâàííÿ äàíèõ ìຠáóòè ïîäâ³éíå ñëîâî  8 */
#define AL 8

/* ìàñèâ â³äë³ê³â âõ³äíîãî ñèãíàëó òà âèõ³äíîãî */
#pragma DATA_ALIGN(in_signal,AL) // âèð³âíþâàííÿ
float   in_signal [2*N]; // äëÿ çàïîâíåííÿ ñèãíàëîì
// 2*N - äëÿ REAL i IMAGIN ñêëàäîâèõ  êîìïëåêñíîãî ñèãíàëó

/* ìàñèâ â³äë³ê³â âõ³äíîãî ñèãíàëó òà âèõ³äíîãî äëÿ ØÏÔ */
#pragma DATA_ALIGN(in_sig_fft,AL) // âèð³âíþâàííÿ
float   in_sig_fft [2*N]; // äëÿ çàïîâíåííÿ ñèãíàëîì
// ï³ñëÿ ØÏÔ öåé ìàñèâ çì³íèòüñÿ

#pragma DATA_ALIGN(out_signal,AL) // âèð³âíþâàííÿ
float   out_signal [2*N]; // äëÿ ñïåêòðó ñèãíàëó

#pragma DATA_ALIGN(w_sp, AL)
float   w_sp [N]; // äëÿ òàáëèö³ cos | sin - Twiddle factor

// ìàñèâè äëÿ ä³éñíî¿ ³ óÿâíî¿ ñêëàäîâèõ âèõ³äíîãî ñèãíàëó
float y_real_sp [N];
float y_imag_sp [N];
// ìàñèâ äëÿ ìîäóëÿ ä³éñíî¿ ³ óÿâíî¿ ñêëàäîâèõ
float a4h[N];
float a4h_out[N/2];

// ïðîòîòèïè ô-³é
void generateInput();
void seperateRealImg (float *real, float * img, float * cmplx, int size_cmplx);
void tw_gen (float *w, int n);
void magnitude(float *in_real, float * in_img, float * out_arr, int size);


int main(void) {
	int i;
	/* Ãåíåðóâàííÿ ñèãíàëó */
	generateInput();

	/* Ôóíêö³ÿ ãåíåðóº ìàñèâ (òàáëèöþ) êîñèíóñ³â òà ñ³íóñ³â*/
	tw_gen(w_sp, N);

	// ðåàë³çàö³ÿ ØÏÔ
	DSPF_sp_fftSPxSP(N, in_sig_fft, w_sp, out_signal, brev, 4, 0, N);

	/* ðîçä³ëåííÿ êîìïëåêñíîãî ñèãíàëó íà real ³ imaginary äàí³ */
	seperateRealImg (y_real_sp, y_imag_sp, out_signal, N);

	// ìîäóëü
	magnitude(y_real_sp, y_imag_sp, a4h, N);

	// îá÷èñëåííÿ àìïë³òóä ãàðìîí³ê
	for (i = 1; i < N/2; ++i){
		a4h_out[i] = a4h[i] * 2 / N;
	}
	a4h_out[0] /= N;

	i=0;// for breakpoint

	return 0;
}



/*
    Ôóíêö³ÿ ãåíåðóº ñèãíàë ïåâíî¿ ÷àñòîòè ³ çàïèñóº â³äë³êè â ìàñèâ
*/
void generateInput () {
    int   i;
    float FreqSignal1, sinWaveMag1 ;
    float FreqSignal2, sinWaveMag2 ;
    float real_s, img_s ; // äëÿ ðåàëüíî¿ òà óÿâíî¿ ñêëàäîâî¿

    float FreqSample;

    /* ÷àñòîòà  äèñêðåòèçàö³¿ Hz*/
    FreqSample = 48000;

    /* Àìïë³òóäà ñèãíàëó */
    sinWaveMag1 = 5;
    sinWaveMag2 = 10;

    /* ÷àñòîòà  ñèãíàëó Hz*/
    FreqSignal1 = 2000;
    FreqSignal2 = 5550;

    /* ãåíåðóâàííÿ ñèãíàëó ä³éñíèõ òà óÿâíèõ ñêëàäîâèõ ñèãíàëó */
	for (i = 0; i < N; i++) {
		real_s  = (float) (
				sinWaveMag1 * cos(2*3.14*i * FreqSignal1 /FreqSample)+
				sinWaveMag2 * cos(2*3.14*i* FreqSignal2 /FreqSample)
		);

		img_s = (float)0.0;

		in_signal[2*i] = real_s;
		in_signal[2*i + 1]  = img_s;
	}

	// êîï³ÿ ìàñèâó â in_sig_fft
	for (i = 0; i < N; i++) {
		in_sig_fft[2*i] = in_signal[2*i];
		in_sig_fft[2*i + 1]  = in_signal[2*i+1];
	}

}

/*
    Ôóíêö³ÿ ãåíåðóº ìàñèâ (òàáëèöþ) êîñèíóñ³â òà ñ³íóñ³â  äëÿ ØÏÔ
*/

void tw_gen (float *w, int n)
{
    int i, j, k;
    const double PI = 3.141592654;

    for (j = 1, k = 0; j <= n >> 2; j = j << 2)
    {
        for (i = 0; i < n >> 2; i += j)
        {
#ifdef _LITTLE_ENDIAN
            w[k]     = (float) sin (2 * PI * i / n);
            w[k + 1] = (float) cos (2 * PI * i / n);
            w[k + 2] = (float) sin (4 * PI * i / n);
            w[k + 3] = (float) cos (4 * PI * i / n);
            w[k + 4] = (float) sin (6 * PI * i / n);
            w[k + 5] = (float) cos (6 * PI * i / n);
#else
            w[k]     = (float)  cos (2 * PI * i / n);
            w[k + 1] = (float) -sin (2 * PI * i / n);
            w[k + 2] = (float)  cos (4 * PI * i / n);
            w[k + 3] = (float) -sin (4 * PI * i / n);
            w[k + 4] = (float)  cos (6 * PI * i / n);
            w[k + 5] = (float) -sin (6 * PI * i / n);
#endif
            k += 6;
        }
    }
}



/*
    Ôóíêö³ÿ seperateRealImg
    äëÿ ðîçä³ëåííÿ real and imaginary äàíèõ ï³ñëÿ ØÏÔ
    Âîíà ïîòð³áíà äëÿ òîãî, ùîá â³äîáðàçèòè ãðàô³÷íî äàí³,
    âèêîðèñòîâóþ÷è CCS graph
*/

void seperateRealImg (float *real, float * img, float * cmplx, int size_cmplx) {
    int i, j;

    for (i = 0, j = 0; j < size_cmplx; i+=2, j++) {
    	real[j] = cmplx[i];
    	img[j] = cmplx[i + 1];
    }
}

/*
 Ôóíêö³ÿ  îá÷èñëåííÿ ìîäóëÿ êîìïëåêñíîãî ÷èñëà
 */
void magnitude(float *in_real, float * in_img, float * out_arr, int size){
	int i;
	 for (i = 0; i < size; i++) {
		 out_arr[i] = (float)sqrt(in_real[i]* in_real[i] + in_img[i]*in_img[i]);
	    }
}

// from some paper
/*
 void tw_gen (float *w, int n)
{
    int i, j, k;
    double x_t, y_t, theta1, theta2, theta3;
    const double PI = 3.141592654;

    for (j = 1, k = 0; j <= n >> 2; j = j << 2)
    {
        for (i = 0; i < n >> 2; i += j)
        {
            theta1 = 2 * PI * i / n;
            x_t = cos (theta1);
            y_t = sin (theta1);
            w[k] = (float) x_t;
            w[k + 1] = (float) y_t;

            theta2 = 4 * PI * i / n;
            x_t = cos (theta2);
            y_t = sin (theta2);
            w[k + 2] = (float) x_t;
            w[k + 3] = (float) y_t;

            theta3 = 6 * PI * i / n;
            x_t = cos (theta3);
            y_t = sin (theta3);
            w[k + 4] = (float) x_t;
            w[k + 5] = (float) y_t;
            k += 6;
        }
    }
}
*/