SIM/qucs_s
1
0
Fork 0
mirror of https://github.com/ra3xdh/qucs_s synced 2025-03-28 21:13:26 +00:00
Code Issues Packages Projects Releases Wiki Activity

Added SallenKey bandpass filter calculation. It works. MFB bandpass doesnot works.

Browse Source
This commit is contained in:
Vadim Kuznetzov 2014-09-06 15:50:10 +04:00 committed by Guilherme Brondani Torri
parent 9d2d1e7c77
commit 7074d2e6e1
5 changed files with 181 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
qucs-activefilter/filter.cpp
View File

@ -39,12 +39,16 @@ Filter::Filter(Filter::FilterFunc ffunc_, Filter::FType type_, FilterParam par)
TW = par.TW;
BW = fabs(Fu -Fl);
F0 = sqrt(Fu*Fl);
if (ftype==Filter::BandPass) { // BandPass
Fc=BW; // cutoff freq. of LPF prototype
float Fs1 = Fu + TW;
float Fs1lp = fabsf(Fs1 - (F0*F0)/Fs1); // stopband freq. of LPF prototype
float Fs2 = Fl - TW;
float Fs2lp = fabsf(Fs2 - (F0*F0)/Fs2);
Fs = std::min(Fs1lp,Fs2lp);
} else if (ftype==Filter::BandStop) { // BandStop
}
Ap = 3.0;
As = 20.0;
qDebug()<<Fc<<Fs;

79
qucs-activefilter/mfbfilter.cpp
View File

@ -196,6 +196,16 @@ void MFBfilter::createHighPassSchematic(QString &s)
s += "</Wires>\n";
}
void MFBfilter::createBandPassSchematic(QString &s)
{
}
void MFBfilter::createBandStopSchematic(QString &s)
{
}
void MFBfilter::calcHighPass()
{
float R1,R2,C1,C2;
@ -259,3 +269,72 @@ void MFBfilter::calcLowPass()
this->calcFirstOrder();
}
void MFBfilter::calcBandPass()
{
float W0 = 2*M_PI*F0;
float R1,R2,R3,C1,C2;
//float rho = Kv/Q;
//float gamma = 1.0;
int cnt = 1;
for (int k=1; k <= order/2; k++) {
float re = Poles.at(k-1).real();
float im = Poles.at(k-1).imag();
float B = -2.0*re;
float C = re*re + im*im;
float H = C + 4.0*Q*Q;
float E = (1.0/B)*sqrt(0.5*(H+sqrt(H*H-(4.0*B*B*Q*Q))));
float F = (B*E)/Q;
float D = 0.5*(F+sqrt(F*F-4.0));
qDebug()<<D<<E<<Q;
float rho = Kv*sqrt(C)/Q;
float beta = D/E;
float gamma = D*D;
C1 = 10.0/F0;
C2 = C1*(rho*beta-gamma)/gamma;
R1 = 1.0/(rho*W0*C1);
R2 = beta/((C1*(gamma-rho*beta)+gamma*C2)*W0);
R3 = (1.0/C1+1.0/C2)/(beta*W0);
RC_elements current_section;
current_section.N = cnt;
current_section.R1 = R1;
current_section.R2 = R2;
current_section.R3 = R3;
current_section.C1 = C1;
current_section.C2 = C2;
Sections.append(current_section);
cnt++;
beta = 1.0/(D*E);
gamma = 1.0/(D*D);
C1 = 10.0/F0;
C2 = C1*(rho*beta-gamma)/gamma;
R1 = 1.0/(rho*W0*C1);
R2 = beta/((C1*(gamma-rho*beta)+gamma*C2)*W0);
R3 = (1.0/C1+1.0/C2)/(beta*W0);
current_section.N = cnt;
current_section.R1 = R1;
current_section.R2 = R2;
current_section.R3 = R3;
current_section.C1 = C1;
current_section.C2 = C2;
Sections.append(current_section);
cnt++;
}
}
void MFBfilter::calcBandStop()
{
}

4
qucs-activefilter/mfbfilter.h
View File

@ -27,8 +27,12 @@ class MFBfilter : public Filter
protected:
void calcHighPass();
void calcLowPass();
void calcBandPass();
void calcBandStop();
void createHighPassSchematic(QString &s);
void createLowPassSchematic(QString &s);
void createBandPassSchematic(QString &s);
void createBandStopSchematic(QString &s);
public:
MFBfilter(Filter::FilterFunc ffunc_, Filter::FType type_, FilterParam par);

84
qucs-activefilter/sallenkey.cpp
View File

@ -117,6 +117,78 @@ void SallenKey::calcHighPass()
calcFirstOrder();
}
void SallenKey::calcBandPass()
{
float W0 = 2*M_PI*F0;
float R1,R2,R3,R4,C1;
//float rho = Kv/Q;
//float gamma = 1.0;
int cnt = 1;
for (int k=1; k <= order/2; k++) {
float re = Poles.at(k-1).real();
float im = Poles.at(k-1).imag();
float B = -2.0*re;
float C = re*re + im*im;
float H = C + 4.0*Q*Q;
float E = (1.0/B)*sqrt(0.5*(H+sqrt(H*H-(4.0*B*B*Q*Q))));
float F = (B*E)/Q;
float D = 0.5*(F+sqrt(F*F-4.0));
qDebug()<<D<<E<<Q;
float rho = Kv*sqrt(C)/Q;
float beta = D/E;
float gamma = D*D;
C1 = 10.0/F0;
R1 = 2.0/(rho*W0*C1);
R2 = 2.0/((-beta+sqrt((rho-beta)*(rho-beta)+8.0*gamma))*W0*C1);
R3 = (1.0/R1+1.0/R2)/(gamma*W0*W0*C1*C1);
R4 = 2.0*R3;
RC_elements current_section;
current_section.N = cnt;
current_section.R1 = 1000*R1;
current_section.R2 = 1000*R2;
current_section.R3 = 1000*R3;
current_section.R4 = 1000*R4;
current_section.C1 = C1;
current_section.C2 = C1;
Sections.append(current_section);
cnt++;
beta = 1.0/(D*E);
gamma = 1.0/(D*D);
C1 = 10.0/F0;
R1 = 2.0/(rho*W0*C1);
R2 = 2.0/((-beta+sqrt((rho-beta)*(rho-beta)+8.0*gamma))*W0*C1);
R3 = (1.0/R1+1.0/R2)/(gamma*W0*W0*C1*C1);
R4 = 2.0*R3;
current_section.N = cnt;
current_section.R1 = 1000*R1;
current_section.R2 = 1000*R2;
current_section.R3 = 1000*R3;
current_section.R4 = 1000*R4;
current_section.C1 = C1;
current_section.C2 = C1;
Sections.append(current_section);
cnt++;
}
}
void SallenKey::calcBandStop()
{
}
void SallenKey::createHighPassSchematic(QString &s)
{
int const N_R=4; // number of resisitors in 2-order Sallen-Key stage
@ -279,3 +351,15 @@ void SallenKey::createLowPassSchematic(QString &s)
s += "</Wires>\n";
}
void SallenKey::createBandPassSchematic(QString &s)
{
}
void SallenKey::createBandStopSchematic(QString &s)
{
}

4
qucs-activefilter/sallenkey.h
View File

@ -31,8 +31,12 @@ protected:
void calcHighPass();
void calcLowPass();
void calcBandPass();
void calcBandStop();
void createHighPassSchematic(QString &s);
void createLowPassSchematic(QString &s);
void createBandPassSchematic(QString &s);
void createBandStopSchematic(QString &s);
public:
SallenKey(Filter::FilterFunc ffunc_, Filter::FType type_, FilterParam par);