void PeriodogramComponent::process()
{
//Get a DataSet from the input DataBuffer
DataSet< complex<float> >* readDataSet = NULL;
getInputDataSet("input1", readDataSet);
std::size_t size = readDataSet->data.size();
//Get a DataSet from the output DataBuffer
DataSet< float >* writeDataSet = NULL;
getOutputDataSet("output1", writeDataSet, x_blocksize);
//FFT process
//float *data =(float*) malloc (size*sizeof(float));
float data[2*size],PSDresult[x_blocksize];
for(int i=0;i<size;i++)
{
data[2*i+1]=readDataSet->data[i].real();
data[2*i]=readDataSet->data[i].imag();
}
periodogram(size,x_blocksize,data,PSDresult);
log10Array(PSDresult,x_blocksize);
for(int i=0;i<x_blocksize;i++)
{
writeDataSet->data[i] = PSDresult[i];
}
//Copy the timestamp and sample rate for the DataSets
writeDataSet->timeStamp = readDataSet->timeStamp;
writeDataSet->sampleRate = readDataSet->sampleRate;
//Release the DataSets
releaseInputDataSet("input1", readDataSet);
releaseOutputDataSet("output1", writeDataSet);
}
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;
}