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Impedance renormalization moved to de-embedding

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This commit is contained in:
Jan Käberich 2022-03-17 18:24:18 +01:00
parent d08388f903
commit 4307a392fb
42 changed files with 584 additions and 330 deletions
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68
Software/PC_Application/VNA/Deembedding/twothru.cpp
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@ -12,19 +12,14 @@ using namespace std;
TwoThru::TwoThru()
{
Z0 = Preferences::getInstance().Acquisition.refImp;
Z0 = 50.0;
}
void TwoThru::transformDatapoint(Protocol::Datapoint &p)
void TwoThru::transformDatapoint(VNAData &p)
{
// correct measurement
if(points.size() > 0) {
auto S11 = complex<double>(p.real_S11, p.imag_S11);
auto S12 = complex<double>(p.real_S12, p.imag_S12);
auto S21 = complex<double>(p.real_S21, p.imag_S21);
auto S22 = complex<double>(p.real_S22, p.imag_S22);
Sparam S(S11, S12, S21, S22);
Tparam meas(S);
Tparam meas(p.S);
Tparam inv1, inv2;
if(p.frequency < points.front().freq) {
@ -54,15 +49,7 @@ void TwoThru::transformDatapoint(Protocol::Datapoint &p)
// perform correction
Tparam corrected = inv1*meas*inv2;
// transform back into S parameters
S = Sparam(corrected);
p.real_S11 = real(S.m11);
p.imag_S11 = imag(S.m11);
p.real_S12 = real(S.m12);
p.imag_S12 = imag(S.m12);
p.real_S21 = real(S.m21);
p.imag_S21 = imag(S.m21);
p.real_S22 = real(S.m22);
p.imag_S22 = imag(S.m22);
p.S = Sparam(corrected);
}
}
@ -112,7 +99,7 @@ void TwoThru::updateGUI()
}
}
void TwoThru::measurementCompleted(std::vector<Protocol::Datapoint> m)
void TwoThru::measurementCompleted(std::vector<VNAData> m)
{
if (measuring2xthru) {
measurements2xthru = m;
@ -223,7 +210,7 @@ void TwoThru::fromJSON(nlohmann::json j)
}
}
std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<Protocol::Datapoint> data_2xthru)
std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<VNAData> data_2xthru)
{
// calculate error boxes, see https://www.freelists.org/post/si-list/IEEE-P370-Opensource-Deembedding-MATLAB-functions
// create vectors of S parameters
@ -242,10 +229,10 @@ std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<Protocol::D
// ignore possible DC point
continue;
}
S11.push_back(complex<double>(m.real_S11, m.imag_S11));
S12.push_back(complex<double>(m.real_S12, m.imag_S12));
S21.push_back(complex<double>(m.real_S21, m.imag_S21));
S22.push_back(complex<double>(m.real_S22, m.imag_S22));
S11.push_back(m.S.m11);
S12.push_back(m.S.m12);
S21.push_back(m.S.m21);
S22.push_back(m.S.m22);
f.push_back(m.frequency);
}
auto n = f.size();
@ -403,7 +390,7 @@ std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<Protocol::D
return ret;
}
std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<Protocol::Datapoint> data_2xthru, std::vector<Protocol::Datapoint> data_fix_dut_fix, double z0)
std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<VNAData> data_2xthru, std::vector<VNAData> data_fix_dut_fix, double z0)
{
vector<Point> ret;
@ -427,19 +414,13 @@ std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<Protocol::D
vector<Sparam> p;
vector<double> f;
for(auto d : data_2xthru) {
p.push_back(Sparam(complex<double>(d.real_S11, d.imag_S11),
complex<double>(d.real_S12, d.imag_S12),
complex<double>(d.real_S21, d.imag_S21),
complex<double>(d.real_S22, d.imag_S22)));
p.push_back(d.S);
f.push_back(d.frequency);
}
auto data_2xthru_Sparam = p;
vector<Sparam> data_fix_dut_fix_Sparam;
for(auto d : data_fix_dut_fix) {
data_fix_dut_fix_Sparam.push_back(Sparam(complex<double>(d.real_S11, d.imag_S11),
complex<double>(d.real_S12, d.imag_S12),
complex<double>(d.real_S21, d.imag_S21),
complex<double>(d.real_S22, d.imag_S22)));
data_fix_dut_fix_Sparam.push_back(d.S);
}
// grabbing S21
@ -682,9 +663,9 @@ std::vector<TwoThru::Point> TwoThru::calculateErrorBoxes(std::vector<Protocol::D
return ret;
}
std::vector<Protocol::Datapoint> TwoThru::interpolateEvenFrequencySteps(std::vector<Protocol::Datapoint> input)
std::vector<VNAData> TwoThru::interpolateEvenFrequencySteps(std::vector<VNAData> input)
{
vector<Protocol::Datapoint> ret;
vector<VNAData> ret;
if(input.size() > 1) {
int size = input.size();
double freqStep = 0.0;
@ -706,8 +687,8 @@ std::vector<Protocol::Datapoint> TwoThru::interpolateEvenFrequencySteps(std::vec
// needs to interpolate
double freq = freqStep;
while(freq <= input.back().frequency) {
Protocol::Datapoint interp;
auto it = lower_bound(input.begin(), input.end(), freq, [](const Protocol::Datapoint &lhs, const double f) -> bool {
VNAData interp;
auto it = lower_bound(input.begin(), input.end(), freq, [](const VNAData &lhs, const double f) -> bool {
return lhs.frequency < f;
});
if(it->frequency == freq) {
@ -718,15 +699,14 @@ std::vector<Protocol::Datapoint> TwoThru::interpolateEvenFrequencySteps(std::vec
it--;
auto low = *it;
double alpha = (freq - low.frequency) / (high.frequency - low.frequency);
interp.real_S11 = low.real_S11 * (1.0 - alpha) + high.real_S11 * alpha;
interp.imag_S11 = low.imag_S11 * (1.0 - alpha) + high.imag_S11 * alpha;
interp.real_S12 = low.real_S12 * (1.0 - alpha) + high.real_S12 * alpha;
interp.imag_S12 = low.imag_S12 * (1.0 - alpha) + high.imag_S12 * alpha;
interp.real_S21 = low.real_S21 * (1.0 - alpha) + high.real_S21 * alpha;
interp.imag_S21 = low.imag_S21 * (1.0 - alpha) + high.imag_S21 * alpha;
interp.real_S22 = low.real_S22 * (1.0 - alpha) + high.real_S22 * alpha;
interp.imag_S22 = low.imag_S22 * (1.0 - alpha) + high.imag_S22 * alpha;
interp.S.m11 = low.S.m11 * (1.0 - alpha) + high.S.m11 * alpha;
interp.S.m12 = low.S.m12 * (1.0 - alpha) + high.S.m12 * alpha;
interp.S.m21 = low.S.m21 * (1.0 - alpha) + high.S.m21 * alpha;
interp.S.m22 = low.S.m22 * (1.0 - alpha) + high.S.m22 * alpha;
interp.cdbm = low.cdbm * (1.0 - alpha) + high.cdbm * alpha;
interp.reference_impedance = low.reference_impedance * (1.0 - alpha) + high.reference_impedance * alpha;
}
interp.pointNum = it->pointNum;
interp.frequency = freq;
ret.push_back(interp);
freq += freqStep;