diff options
Diffstat (limited to '339/CH9/EX9.14/ex9_14.sce')
-rwxr-xr-x | 339/CH9/EX9.14/ex9_14.sce | 128 |
1 files changed, 64 insertions, 64 deletions
diff --git a/339/CH9/EX9.14/ex9_14.sce b/339/CH9/EX9.14/ex9_14.sce index 0b6e65f6a..ae26754a0 100755 --- a/339/CH9/EX9.14/ex9_14.sce +++ b/339/CH9/EX9.14/ex9_14.sce @@ -1,65 +1,65 @@ -global Z0;
-Z0=50;
-
-//define the S-parameters of the transistor
-s11=0.3*exp(%i*(+30)/180*%pi);
-s12=0.2*exp(%i*(-60)/180*%pi);
-s21=2.5*exp(%i*(-80)/180*%pi);
-s22=0.2*exp(%i*(-15)/180*%pi);
-
-//pick the noise parameters of the transistor
-Fmin_dB=1.5
-Fmin=10^(Fmin_dB/10);
-Rn=4;
-Gopt=0.5*exp(%i*45/180*%pi);
-
-//compute a noise circle
-Fk_dB=1.6;
-Fk=10^(Fk_dB/10);
-
-
-Qk=abs(1+Gopt)^2*(Fk-Fmin)/(4*Rn/Z0) //noise circle parameter
-dfk=Gopt/(1+Qk); //circle center location
-rfk=sqrt((1-abs(Gopt)^2)*Qk+Qk^2)/(1+Qk) //circle radius
-
-
-//plot a noise circle
-a=[0:360]/180*%pi;
-set(gca(),"auto_clear","off");
-plot(real(dfk)+rfk*cos(a),imag(dfk)+rfk*sin(a),'b','linewidth',2);
-
-// plot optimal reflection coefficient
-plot(real(Gopt),imag(Gopt),'bo');
-
-
-//specify the desired gain
-G_goal_dB=8;
-G_goal=10^(G_goal_dB/10);
-
-//find the constant operating power gain circles
-go=G_goal/abs(s21)^2; // normalized the gain
-dgo=go*conj(s22-conj(s11))/(1+go*(abs(s22)^2)); //center
-
-rgo=sqrt(1-2*K*go*abs(s12*s21)+go^2*abs(s12*s21)^2);
-rgo=rgo/abs(1+go*(abs(s22)^2));
-
-//map a constant gain circle into the Gs plane
-rgs=rgo*abs(s12*s21/(abs(1-s22*dgo)^2-rgo^2*abs(s22)^2));
-dgs=((1-s22*dgo)*conj(s11-dgo)-rgo^2*s22)/(abs(1-s22*dgo)^2-rgo^2*abs(s22)^2);
-
-//plot a constant gain circle in the Smith Chart
-set(gca(),"auto_clear","off");
-plot(real(dgs)+rgs*cos(a),imag(dgs)+rgs*sin(a),'r','linewidth',2);
-
-
-
-//choose a source reflection coefficient Gs
-Gs=dgs+%i*rgs;
-plot(real(Gs), imag(Gs), 'ro');
-//text(real(Gs)-0.05,imag(Gs)+0.08,'\bf\Gamma_S');
-
-//find the actual noise figure
-F=Fmin+4*Rn/Z0*abs(Gs-Gopt)^2/(1-abs(Gs)^2)/abs(1+Gopt)^2;
-
-//print out the actual noise figure
+global Z0; +Z0=50; + +//define the S-parameters of the transistor +s11=0.3*exp(%i*(+30)/180*%pi); +s12=0.2*exp(%i*(-60)/180*%pi); +s21=2.5*exp(%i*(-80)/180*%pi); +s22=0.2*exp(%i*(-15)/180*%pi); + +//pick the noise parameters of the transistor +Fmin_dB=1.5 +Fmin=10^(Fmin_dB/10); +Rn=4; +Gopt=0.5*exp(%i*45/180*%pi); + +//compute a noise circle +Fk_dB=1.6; +Fk=10^(Fk_dB/10); + + +Qk=abs(1+Gopt)^2*(Fk-Fmin)/(4*Rn/Z0) //noise circle parameter +dfk=Gopt/(1+Qk); //circle center location +rfk=sqrt((1-abs(Gopt)^2)*Qk+Qk^2)/(1+Qk) //circle radius + + +//plot a noise circle +a=[0:360]/180*%pi; +mtlb_hold on +plot(real(dfk)+rfk*cos(a),imag(dfk)+rfk*sin(a),'b','linewidth',2); + +// plot optimal reflection coefficient +plot(real(Gopt),imag(Gopt),'bo'); + + +//specify the desired gain +G_goal_dB=8; +G_goal=10^(G_goal_dB/10); +K = 1.18; +//find the constant operating power gain circles +go=G_goal/abs(s21)^2; // normalized the gain +dgo=go*conj(s22-conj(s11))/(1+go*(abs(s22)^2)); //center + +rgo=sqrt(1-2*K*go*abs(s12*s21)+go^2*abs(s12*s21)^2); +rgo=rgo/abs(1+go*(abs(s22)^2)); + +//map a constant gain circle into the Gs plane +rgs=rgo*abs(s12*s21/(abs(1-s22*dgo)^2-rgo^2*abs(s22)^2)); +dgs=((1-s22*dgo)*conj(s11-dgo)-rgo^2*s22)/(abs(1-s22*dgo)^2-rgo^2*abs(s22)^2); + +//plot a constant gain circle in the Smith Chart +mtlb_hold on +plot(real(dgs)+rgs*cos(a),imag(dgs)+rgs*sin(a),'r','linewidth',2); + + + +//choose a source reflection coefficient Gs +Gs=dgs+%i*rgs; +plot(real(Gs), imag(Gs), 'ro'); +//text(real(Gs)-0.05,imag(Gs)+0.08,'\bf\Gamma_S'); + +//find the actual noise figure +F=Fmin+4*Rn/Z0*abs(Gs-Gopt)^2/(1-abs(Gs)^2)/abs(1+Gopt)^2; + +//print out the actual noise figure Actual_F_dB=10*log10(F)
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