救我一命:请教如何求多导体传输线的S参数
12-08
我学习中遇到求多导体传输线的S参数,经过查找相关论文及亲自推导出来的S参数的表达式都为:
S11=-inv((U-C)*P*(U-inv(C))+(U+C)*inv(P)*(U+inv(C)))
*((U-C)*P*(U+inv(C))+(U+C)*inv(P)*(U-inv(C)));
S12=4*inv((U-C)*P*(U-inv(C))+(U+C)*inv(P)*(U+inv(C)));
其中U为单位阵,C=Zr*inv(Zc),P=q*expm(-hleng)*inv(q);q为Z*Y的特征向量阵,h为Z*Y对应的特征值平方根阵,Z为单位长度的阻抗,Y为单位长度的导纳,Zr为参考阻抗,Zc为特征阻抗,l为线的长度。
可是我用一个例子去检验这个公式时,发现当是单根线时上面的公式成立,当为多根线时,求得的结果却是错误的,不知道错误的原因在哪里,向各位高手请教!在下先谢谢了!
具体的例子为:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 两根线的程序
clear all
R=[1,1;1,1];%已知两根线的R
L=[3,2;2,3];%已知两根线的L
C=[2,1;1,2];%已知两根线的C
G=zeros(2,2);%已知两根线的G
leng=1;%已知线长
r1=50*ones(1,2);
zr=diag(r1);%已知参考矩阵
u=0.02*zr;%单位阵
Z=R+L*j;%Z矩阵
Y=G+C*j;%Y矩阵
[q,h1]=eig(Z*Y,'nobalance');%求Z*Y的特征向量阵q和特征值阵h1
h=sqrt(h1);%求h1的平方根
zc=q*inv(h)*inv(q)*Z;%求特征阻抗
cc=zr*inv(zc);%求c
p=q*expm(-hleng)*inv(q);%求p
s11=-zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*((u-cc)*p*(u+cc^-1)+(u+cc)*(p^-1)*(u-cc^-1))*zr^(0.5);%求s11
s12=4*zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*zr^(0.5);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%% 计算得到的S参数结果:
s11 =
-0.9777 - 0.0271i 0.0209 - 0.0015i
0.0209 - 0.0015i -0.9777 - 0.0271i
s12 =
-0.0083 - 0.0022i -0.0095 + 0.0452i
-0.0095 + 0.0452i -0.0083 - 0.0022i
%%%%%%%%
%%%%%%%%% 而实际的正确结果应为:
s11=
-0.9931 - 0.0149i 0.0061 + 0.0220i
0.0061 + 0.0220i -0.9931 - 0.0149i
s12=
0.0031 - 0.0019i -0.0111 - 0.0199i
-0.0111 - 0.0199i 0.0031 - 0.0019i
%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%单根线的程序
clear all
R=[1];%已知两根线的R
L=[3];%已知两根线的L
C=[2];%已知两根线的C
G=zeros(1,1);%已知两根线的G
leng=1;%已知线长
r1=50*ones(1,1);
zr=diag(r1);%已知参考矩阵
u=0.02*zr;%单位阵
Z=R+L*j;%Z矩阵
Y=G+C*j;%Y矩阵
[q,h1]=eig(Z*Y,'nobalance');%求Z*Y的特征向量阵q和特征值阵h1
h=sqrt(h1);%求h1的平方根
zc=q*inv(h)*inv(q)*Z;%求特征阻抗
cc=zr*inv(zc);%求c
p=q*expm(-hleng)*inv(q);%求p
s11=-zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*((u-cc)*p*(u+cc^-1)+(u+cc)*(p^-1)*(u-cc^-1))*zr^(0.5);%求s11
s12=4*zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*zr^(0.5);
>> s11为正确的结果
s11 =
-0.9520 + 0.0336i
S11=-inv((U-C)*P*(U-inv(C))+(U+C)*inv(P)*(U+inv(C)))
*((U-C)*P*(U+inv(C))+(U+C)*inv(P)*(U-inv(C)));
S12=4*inv((U-C)*P*(U-inv(C))+(U+C)*inv(P)*(U+inv(C)));
其中U为单位阵,C=Zr*inv(Zc),P=q*expm(-hleng)*inv(q);q为Z*Y的特征向量阵,h为Z*Y对应的特征值平方根阵,Z为单位长度的阻抗,Y为单位长度的导纳,Zr为参考阻抗,Zc为特征阻抗,l为线的长度。
可是我用一个例子去检验这个公式时,发现当是单根线时上面的公式成立,当为多根线时,求得的结果却是错误的,不知道错误的原因在哪里,向各位高手请教!在下先谢谢了!
具体的例子为:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 两根线的程序
clear all
R=[1,1;1,1];%已知两根线的R
L=[3,2;2,3];%已知两根线的L
C=[2,1;1,2];%已知两根线的C
G=zeros(2,2);%已知两根线的G
leng=1;%已知线长
r1=50*ones(1,2);
zr=diag(r1);%已知参考矩阵
u=0.02*zr;%单位阵
Z=R+L*j;%Z矩阵
Y=G+C*j;%Y矩阵
[q,h1]=eig(Z*Y,'nobalance');%求Z*Y的特征向量阵q和特征值阵h1
h=sqrt(h1);%求h1的平方根
zc=q*inv(h)*inv(q)*Z;%求特征阻抗
cc=zr*inv(zc);%求c
p=q*expm(-hleng)*inv(q);%求p
s11=-zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*((u-cc)*p*(u+cc^-1)+(u+cc)*(p^-1)*(u-cc^-1))*zr^(0.5);%求s11
s12=4*zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*zr^(0.5);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%% 计算得到的S参数结果:
s11 =
-0.9777 - 0.0271i 0.0209 - 0.0015i
0.0209 - 0.0015i -0.9777 - 0.0271i
s12 =
-0.0083 - 0.0022i -0.0095 + 0.0452i
-0.0095 + 0.0452i -0.0083 - 0.0022i
%%%%%%%%
%%%%%%%%% 而实际的正确结果应为:
s11=
-0.9931 - 0.0149i 0.0061 + 0.0220i
0.0061 + 0.0220i -0.9931 - 0.0149i
s12=
0.0031 - 0.0019i -0.0111 - 0.0199i
-0.0111 - 0.0199i 0.0031 - 0.0019i
%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%单根线的程序
clear all
R=[1];%已知两根线的R
L=[3];%已知两根线的L
C=[2];%已知两根线的C
G=zeros(1,1);%已知两根线的G
leng=1;%已知线长
r1=50*ones(1,1);
zr=diag(r1);%已知参考矩阵
u=0.02*zr;%单位阵
Z=R+L*j;%Z矩阵
Y=G+C*j;%Y矩阵
[q,h1]=eig(Z*Y,'nobalance');%求Z*Y的特征向量阵q和特征值阵h1
h=sqrt(h1);%求h1的平方根
zc=q*inv(h)*inv(q)*Z;%求特征阻抗
cc=zr*inv(zc);%求c
p=q*expm(-hleng)*inv(q);%求p
s11=-zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*((u-cc)*p*(u+cc^-1)+(u+cc)*(p^-1)*(u-cc^-1))*zr^(0.5);%求s11
s12=4*zr^(-0.5)*(inv((u-cc)*p*(u-cc^-1)+(u+cc)*(p^-1)*(u+cc^-1)))*zr^(0.5);
>> s11为正确的结果
s11 =
-0.9520 + 0.0336i
一看就是数学基础巨好的那种,偶老板就喜欢这样的学生
可惜俺的数学巨烂=_=~!!
my god
一看前面这串公式
差点狂喷鲜血数升
相关文章:
- 请教微波与导体和半导体作用的区别(05-08)
- 请问一下电小导体的尺度(05-08)
- 手机天线与电路基板或导体板间隔3mm,从哪里可以查到该数据的出(05-08)
- 在fdtd中通常不考虑导体面的厚度吗?(05-08)
- 一个器件的高频集总参数与接地导体的位置貌似有关系呀?(05-08)
- HFSS里无限大接地导体设置的问题。(05-08)
射频专业培训教程推荐