C++ (Cpp) polar_discriminant Examples

Example #1

File: rtl_fm.c Project: howard0su/rtl-sdr

void fm_demod(struct fm_state *fm)
{
	int i, pcm;
	pcm = polar_discriminant(fm->signal[0], fm->signal[1],
		fm->pre_r, fm->pre_j);
	fm->signal2[0] = (int16_t)pcm;
	for (i = 2; i < (fm->signal_len); i += 2) {
		switch (fm->custom_atan) {
		case 0:
			pcm = polar_discriminant(fm->signal[i], fm->signal[i+1],
				fm->signal[i-2], fm->signal[i-1]);
			break;
		case 1:
			pcm = polar_disc_fast(fm->signal[i], fm->signal[i+1],
				fm->signal[i-2], fm->signal[i-1]);
			break;
		case 2:
			pcm = polar_disc_lut(fm->signal[i], fm->signal[i+1],
				fm->signal[i-2], fm->signal[i-1]);
			break;
		}
		fm->signal2[i/2] = (int16_t)pcm;
	}
	fm->pre_r = fm->signal[fm->signal_len - 2];
	fm->pre_j = fm->signal[fm->signal_len - 1];
	fm->signal2_len = fm->signal_len/2;
}

Example #2

File: rtl_fm.c Project: ldy972/Drone

void fm_demod(struct demod_state *fm)
{
	int i, pcm;
	int16_t *lp = fm->lowpassed;
	pcm = polar_discriminant(lp[0], lp[1],
		fm->pre_r, fm->pre_j);
	fm->result[0] = (int16_t)pcm;
	for (i = 2; i < (fm->lp_len-1); i += 2) {
		switch (fm->custom_atan) {
		case 0:
			pcm = polar_discriminant(lp[i], lp[i+1],
				lp[i-2], lp[i-1]);
			break;
		case 1:
			pcm = polar_disc_fast(lp[i], lp[i+1],
				lp[i-2], lp[i-1]);
			break;
		case 2:
			pcm = polar_disc_lut(lp[i], lp[i+1],
				lp[i-2], lp[i-1]);
			break;
		}
		fm->result[i/2] = (int16_t)pcm;
	}
	fm->pre_r = lp[fm->lp_len - 2];
	fm->pre_j = lp[fm->lp_len - 1];
	fm->result_len = fm->lp_len/2;
}

Example #3

File: rtl_fm.c Project: pavels/rtl-sdr

void fm_demod(struct demod_state *fm)
{
	int i, pcm = 0;
	int16_t *lp = fm->lowpassed;
        int16_t pr = fm->pre_r;
	int16_t pj = fm->pre_j;
	for (i = 0; i < (fm->lp_len-1); i += 2) {
		switch (fm->custom_atan) {
		case 0:
			pcm = polar_discriminant(lp[i], lp[i+1], pr, pj);
			break;
		case 1:
			pcm = polar_disc_fast(lp[i], lp[i+1], pr, pj);
			break;
		case 2:
			pcm = polar_disc_lut(lp[i], lp[i+1], pr, pj);
			break;
		case 3:
			pcm = esbensen(lp[i], lp[i+1], pr, pj);
			break;
		}
		pr = lp[i];
		pj = lp[i+1];
		fm->lowpassed[i/2] = (int16_t)pcm;
	}
	fm->pre_r = pr;
	fm->pre_j = pj;
	fm->lp_len = fm->lp_len / 2;
}

Example #4

File: rtl_fm.c Project: HounD/librtlsdr-android

void fm_demod(struct fm_state *fm)
{
	int i, pcm;
	pcm = polar_discriminant(fm->signal[0], fm->signal[1],
		fm->pre_r, fm->pre_j);
	fm->signal2[0] = (int16_t)pcm;
	for (i = 2; i < (fm->signal_len); i += 2) {
		if (fm->custom_atan) {
			pcm = polar_disc_fast(fm->signal[i], fm->signal[i+1],
				fm->signal[i-2], fm->signal[i-1]);
		} else {
			pcm = polar_discriminant(fm->signal[i], fm->signal[i+1],
				fm->signal[i-2], fm->signal[i-1]);
		}
		fm->signal2[i/2] = (int16_t)pcm;
	}
	fm->pre_r = fm->signal[fm->signal_len - 2];
	fm->pre_j = fm->signal[fm->signal_len - 1];
}