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time domain markers

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This commit is contained in:
Jan Käberich 2020-11-22 21:25:41 +01:00
parent c22d576984
commit 93bf7255c3
17 changed files with 505 additions and 185 deletions
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60
Software/PC_Application/Traces/trace.cpp
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@ -215,6 +215,11 @@ void Trace::updateTimeDomainData()
}
t.impulseResponse = real(frequencyDomain[i]) / fft_bins;
t.stepResponse = last_step;
if(abs(t.stepResponse) < 1.0) {
t.impedance = 50.0 * (1+t.stepResponse) / (1-t.stepResponse);
} else {
t.impedance = numeric_limits<double>::quiet_NaN();
}
last_step += t.impulseResponse;
timeDomain.push_back(t);
}
@ -236,12 +241,67 @@ void Trace::addTDRinterest()
updateTimeDomainData();
}
tdr_users++;
if(tdr_users == 1) {
emit changedTDRstate(true);
}
}
void Trace::removeTDRinterest()
{
if(tdr_users > 0) {
tdr_users--;
if(tdr_users == 0) {
emit changedTDRstate(false);
}
}
}
Trace::TimedomainData Trace::getTDR(double position)
{
TimedomainData ret = {};
if(!TDRactive() || position < 0) {
return ret;
}
int index = 0;
bool exact = false;
double alpha = 0.0;
if(position <= timeDomain.back().time) {
auto lower = lower_bound(timeDomain.begin(), timeDomain.end(), position, [](const TimedomainData &lhs, const double pos) -> bool {
return lhs.time < pos;
});
index = lower - timeDomain.begin();
if(timeDomain.at(index).time == position) {
exact = true;
} else {
alpha = (position - timeDomain.at(index-1).time) / (timeDomain.at(index).time - timeDomain.at(index-1).time);
}
} else {
if(position > timeDomain.back().distance) {
// too high, invalid position
return ret;
}
auto lower = lower_bound(timeDomain.begin(), timeDomain.end(), position, [](const TimedomainData &lhs, const double pos) -> bool {
return lhs.distance < pos;
});
index = lower - timeDomain.begin();
if(timeDomain.at(index).distance == position) {
exact = true;
} else {
alpha = (position - timeDomain.at(index-1).distance) / (timeDomain.at(index).distance - timeDomain.at(index-1).distance);
}
}
if(exact) {
return timeDomain.at(index);
} else {
// need to interpolate
auto low = timeDomain.at(index-1);
auto high = timeDomain.at(index);
ret.time = low.time * (1.0 - alpha) + high.time * alpha;
ret.distance = low.distance * (1.0 - alpha) + high.distance * alpha;
ret.stepResponse = low.stepResponse * (1.0 - alpha) + high.stepResponse * alpha;
ret.impulseResponse = low.impulseResponse * (1.0 - alpha) + high.impulseResponse * alpha;
ret.impedance = low.impedance * (1.0 - alpha) + high.impedance * alpha;
return ret;
}
}