Adam Cooman

YZSHGABT
YY→ZY→SY→HY→GY→AY→BY→T
ZZ→YZ→SZ→HZ→GZ→AZ→BZ→T
SS→YS→ZS→HS→GS→AS→BS→T
HH→YH→ZH→SH→GH→AH→BH→T
GG→YG→ZG→SG→HG→AG→BG→T
AA→YA→ZA→SA→HA→GA→BA→T
BB→YB→ZB→SB→HB→GB→AB→T
TT→YT→ZT→ST→HT→GT→AT→B

From B-parameters to Z-parameters

In matrix form, the formula is

Z=([0010]B+[1000])([0001]B+[0100])1\mathbf{Z} =\left(\begin{bmatrix} 0 & 0\\ 1 & 0 \end{bmatrix}\,\mathbf{B}+\begin{bmatrix} 1 & 0\\ 0 & 0 \end{bmatrix}\right)\,{\left(\begin{bmatrix} 0 & 0\\ 0 & -1 \end{bmatrix}\,\mathbf{B}+\begin{bmatrix} 0 & 1\\ 0 & 0 \end{bmatrix}\right)}^{-1}

While for each element, we obtain

Z11=B22B21Z12=1B21Z21=B11B22B12B21B21Z22=B11B21\begin{align*}Z_{11} &=-\frac{B_{22}}{B_{21}}\\Z_{12} &=-\frac{1}{B_{21}}\\Z_{21} &=-\frac{B_{11}\,B_{22}-B_{12}\,B_{21}}{B_{21}}\\Z_{22} &=-\frac{B_{11}}{B_{21}}\\\end{align*}

The formulas are obtained with the methods explained here. The MATLAB implementation can be found in circuitconversions on Gitlab.

Definitions

[V2I2]=B[V1I1]\begin{bmatrix}V_2 \\-I_2\end{bmatrix} = \mathbf{B}\begin{bmatrix}V_1 \\I_1\end{bmatrix}

[V1V2]=Z[I1I2]\begin{bmatrix}V_1 \\V_2\end{bmatrix} = \mathbf{Z}\begin{bmatrix}I_1 \\I_2\end{bmatrix}