void UmlBroadcastSignalAction::write(FileOut & out) {
write_begin(out, "BroadcastSignalAction");
write_end(out, TRUE);
write_signal(out);
write_close(out);
}
void process_radar_signal(radar &a_radar, vector< valarray<complex<double> > > &y)
{
vector<double> sx;
for(size_t i = 0; i < a_radar.x.size(); i++)
{
double val = ((double)1e6/a_radar.fs)*i;
sx.push_back(val);
}
#if PLOT
write_signal(a_radar.x, sx, "chirp.dat");
#endif
// double PRI = 1.0/PRF;
//compute unambiguous Doppler interval in m/sec
//compute unambiguous Dopper range interval in meters
double vua = (-1) * C*PRF/(2*a_radar.fc);
// double rmin = C*a_radar.T_out[0]/2;
// double rmax = C*a_radar.T_out[1]/2;
// double rua = C/2/PRF;
//convert range samples to absolute range units
int My = y.size();
int Ny = y[0].size();
vector<double> range;
for(int i = 0; i < My; i++)
{
double val = (double(C)/2.0)* ((double)i*(1.0/a_radar.fs) + a_radar.T_out[0])/1e3;
range.push_back(val);
}
vector<int> pulses;
for(int i = 0; i < Ny; i++)
{
pulses.push_back(i);
}
//force oversize FFT, and compute doppler scale factor
int p = nextpow2(Ny);
int Lfft = pow(2.0, p+3);
vector<double> doppler;
for(int i = 0; i < Lfft; i++)
{
double val = ((double)i/(double)Lfft - 0.5) * vua;
doppler.push_back(val);
}
/* dopper process and square-law detect the whole
* unprocessed array
* using Hamming window throughout*/
#if PLOT
range_doppler_plot(y, doppler, Lfft, "doppler_range.dat");
#endif
/* processing the data
* 1. pulse compression
* using time-domain hamming weighting of the
* impulse response for range sidelobe control */
int Ls = a_radar.x.size();
vector<double> hw = hamming(Ls);
valarray<complex<double> > h1(Ls);
for(int i = 0; i < Ls; i++)
{
h1[i] = conj(a_radar.x[Ls-1-i]) * hw[i];
}
int Myp = My + Ls -1;
int Nyp = Ny;
vector< valarray<complex<double> > > yp;
initVector(Myp, Nyp, yp);
conv(h1, y, yp, false);
vector<double> rangep;
for(int i = 0; i < Myp; i++)
{
double rval = (C/2.0)*((double(i)-(Ls-1))*(1.0/a_radar.fs) + a_radar.T_out[0])/1e3;
rangep.push_back(rval);
}
#if PLOT
range_doppler_plot(yp, doppler, Lfft, "doppler_range_compressed.dat");
#endif
/* 2. apply three-pulse canceller in each range bin to raw data */
valarray<complex<double> > h2(3);
h2[0] = complex<double>(1, 0); h2[1] = complex<double>(-2, 0);
h2[2] = complex<double>(1, 0);
vector< valarray<complex<double> > > ypm;
int Nyp2 = Nyp + h2.size() - 1;
initVector(Myp, Nyp2, ypm);
conv(h2, yp, ypm, true);
vector< valarray<complex<double> > > YPM;
vector<double> w = hamming(Ny);
doppler_process(ypm, YPM, w, Lfft);
#if PLOT
range_doppler_plot(ypm, doppler, Lfft, "doppler_range_canceller.dat");
#endif
/*3. search for the range bins with targets
* first noncoherently integrate across the frequency bins*/
int Mypm = YPM.size();
// int Nypm = YPM[0].size();
valarray<double> YPMrange(Mypm);
vector<double> ranges_sort;
for(int i = 0; i < Mypm; i++)
{
double sumr = YPM[i].sum().real();
YPMrange[i] = sumr;
ranges_sort.push_back(sumr);
}
sort(ranges_sort.begin(), ranges_sort.end());
/* median of YPMrange */
int md_ind = (Mypm%2) ? Mypm/2 : (Mypm/2+1);
double Nrange = ranges_sort[md_ind];
/* threshold 8x (9DB) above noise estimate */
double Trange = 8*Nrange;
/* loop identifies which range bins have local peaks above
* the threshold. It also set up a vector */
vector<pair<int, double> > spikesr;
for(int i = 2; i < Mypm-1; i++)
{
if( (YPMrange[i] > YPMrange[i+1]) && (YPMrange[i]>YPMrange[i-1])
&& (YPMrange[i] > Trange) )
{
spikesr.push_back(make_pair(i, YPMrange[i]));
}
}
vector<vector<double> > targets;
/* 4. find the Doppler peak(s) for each range bin having a target(s). Keep
adjoining Doppler values as well to support subsequent interpolation
*/
int Mspikesr = spikesr.size();
for(int i = 0; i < Mspikesr; i++)
{
vector<vector<double> > spikesd_bin;
spikesd_bin.clear();
int rb = spikesr[i].first;
for(int k = 0; k < Lfft; k++)
{
int km1 = k == 0 ? Lfft-1 : k-1;
int kp1 = k == Lfft-1? 0 : k+1;
if( YPM[rb][k].real() > YPM[rb][kp1].real() &&
YPM[rb][k].real() > YPM[rb][km1].real() &&
YPM[rb][k].real() > (double)Nrange/2.0 )
{
vector<double> spikesd;
vector<double> obj;
spikesd.clear();
obj.clear();
// cout << k << " " <<YPM[rb][km1].real()<<" "<<YPM[rb][k].real()
// << " " << YPM[rb][kp1].real() << endl;
spikesd.push_back(k);
spikesd.push_back(YPM[rb][km1].real());
spikesd.push_back(YPM[rb][k].real());
spikesd.push_back(YPM[rb][kp1].real());
double amp, del_k;
double z1 = sqrt(spikesd[1]);
double z2 = sqrt(spikesd[2]);
double z3 = sqrt(spikesd[3]);
peakinterp(amp, del_k, z1, z2, z3);
obj.push_back(amp);
obj.push_back(rangep[rb]);
double vel = ((spikesd[0] + del_k - 1)/Lfft -0.5)*vua;
obj.push_back(vel);
spikesd_bin.push_back(spikesd);
targets.push_back(obj);
}
}
}
cout << "detected targets are:" << endl;
int Mtargets = targets.size();
int Ntargets = targets[0].size();
for(int i = 0; i < Mtargets; i++)
{
for(int j = 0 ; j < Ntargets; j++)
{
cout <<" " << targets[i][j];
}
cout << endl;
}
}
void UmlSendSignalAction::write(FileOut & out) {
write_begin(out, "SendSignalAction");
write_end(out, TRUE);
write_signal(out);
write_close(out);
}
