SPAN_DECLARE(complexf_t) dds_complexf(uint32_t *phase_acc, int32_t phase_rate)
{
complexf_t amp;
amp = complex_setf(dds_lookupx(*phase_acc + (1 << 30)), dds_lookupx(*phase_acc));
*phase_acc += phase_rate;
return amp;
}
SPAN_DECLARE(complexf_t) dds_complex_modf(uint32_t *phase_acc, int32_t phase_rate, float scale, int32_t phase)
{
complexf_t amp;
amp = complex_setf(dds_lookupx(*phase_acc + phase + (1 << 30))*scale,
dds_lookupx(*phase_acc + phase)*scale);
*phase_acc += phase_rate;
return amp;
}
static complexf_t cvec_dot_prodf_dumb(const complexf_t x[], const complexf_t y[], int n)
{
int i;
complexf_t z;
complexf_t z1;
z = complex_setf(0.0f, 0.0f);
for (i = 0; i < n; i++)
{
z1 = complex_mulf(&x[i], &y[i]);
z = complex_addf(&z, &z1);
}
return z;
}
static int periodogram_tests(void)
{
int i;
int j;
int k;
int len;
complexf_t coeffs[PG_WINDOW/2];
complexf_t camp[BLOCK_LEN];
complexf_t last_result;
complexf_t result;
complexf_t phase_offset;
float freq_error;
float pg_scale;
float level;
float scale1;
float scale2;
int32_t phase_rate1;
int32_t phase_rate2;
uint32_t phase_acc1;
uint32_t phase_acc2;
awgn_state_t noise_source_re;
awgn_state_t noise_source_im;
phase_rate1 = DEC_RATIO*dds_phase_ratef(FREQ1 - 5.0f);
phase_rate2 = DEC_RATIO*dds_phase_ratef(FREQ2);
phase_acc1 = 0;
phase_acc2 = 0;
len = periodogram_generate_coeffs(coeffs, FREQ1, DEC_SAMPLE_RATE, PG_WINDOW);
if (len != PG_WINDOW/2)
{
printf("Test failed\n");
return -1;
}
pg_scale = periodogram_generate_phase_offset(&phase_offset, FREQ1, DEC_SAMPLE_RATE, PG_WINDOW);
scale1 = dds_scaling_dbm0f(-6.0f);
scale2 = dds_scaling_dbm0f(-6.0f);
for (k = -50; k < 0; k++)
{
printf("Setting noise to %ddBm0\n", k);
awgn_init_dbm0(&noise_source_re, 1234567, (float) k);
awgn_init_dbm0(&noise_source_im, 7654321, (float) k);
last_result = complex_setf(0.0f, 0.0f);
for (i = 0; i < 100; i++)
{
for (j = 0; j < PG_WINDOW; j++)
{
result = dds_complexf(&phase_acc1, phase_rate1);
camp[j].re = result.re*scale1;
camp[j].im = result.im*scale1;
result = dds_complexf(&phase_acc2, phase_rate2);
camp[j].re += result.re*scale2;
camp[j].im += result.im*scale2;
camp[j].re += awgn(&noise_source_re);
camp[j].im += awgn(&noise_source_im);
}
result = periodogram(coeffs, camp, PG_WINDOW);
level = sqrtf(result.re*result.re + result.im*result.im);
freq_error = periodogram_freq_error(&phase_offset, pg_scale, &last_result, &result);
last_result = result;
if (i == 0)
continue;
printf("Signal level = %.5f, freq error = %.5f\n", level, freq_error);
if (level < scale1*0.8f || level > scale1*1.2f)
{
printf("Test failed - %ddBm0 of noise, signal is %f (%f)\n", k, level, scale1);
return -1;
}
if (freq_error < -10.0f || freq_error > 10.0f)
{
printf("Test failed - %ddBm0 of noise, %fHz error\n", k, freq_error);
return -1;
}
}
}
return 0;
}
SPAN_DECLARE(complexf_t) dds_lookup_complexf(uint32_t phase)
{
return complex_setf(dds_lookupx(phase + (1 << 30)), dds_lookupx(phase));
}
