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S-parameters: Replace S11 by S_1_1 etc. to avoid ambiguity 

when more than 10 ports are measured.
Update to S-parameter script and command wr2sp
This commit is contained in:
Holger Vogt 2022-04-28 11:58:21 +02:00
parent 67726f7f8b
commit 129893b399
2 changed files with 34 additions and 33 deletions
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57
examples/control_structs/s-param.cir
View File

@ -39,7 +39,7 @@ C3 out 0 33.2p
** The following subcircuit to be changed only by an experienced user!
*** Driver and readout
X1 in out S22 S12 S_PARAM
X1 in out S_2_2 S_1_2 S_PARAM
.SUBCKT S_PARAM 22 66 5 7
* Resistors emulate switches with Ron=0.001 and Roff=1e12
@ -58,22 +58,22 @@ R3 5 0 1 ; ground return for measure node 5
*Readout
E2 7 0 6 0 2 ; amplify out port ac voltage by 2
R4 6 8 'Rbase' ; load resistor at output (ac)
Vdc 8 0 DC 'Vbias_out' AC 0 $ dc bias at output (applied through load resistor)
Vdc 8 0 DC 'Vbias_out' AC 0 ; dc bias at output (applied through load resistor)
.ends
** Check the two ac lines below for being equal!
.control
set noaskquit
set filetype=ascii
*** measurement for s11 and s21
*** measurement for s_1_1 and s_2_1
op
** save bias voltages to vector
let Vdcnew=V(X1.1) $ former Vacdc
let Vacdcnew=v(X1.8) $ former Vdc
let Vdcnew=V(X1.1) ; former Vacdc
let Vacdcnew=v(X1.8) ; former Vdc
** first ac measurement (change this line only together with following ac line)
*ac lin 20 0.1G 2G $ use for bip transistor
ac lin 100 2.5MEG 250MEG $ use for Tschebyschef
*ac lin 101 1k 10G $ use for RC
*ac lin 20 0.1G 2G ; use for bip transistor
ac lin 100 2.5MEG 250MEG ; use for Tschebyschef
*ac lin 101 1k 10G ; use for RC
**
** switch input and output
alter R.X1.RS1=1e12
@ -83,38 +83,39 @@ alter R.X1.RS4=0.001
** switch bias voltages between in and out
alter V.X1.Vacdc DC=op1.Vacdcnew
alter V.X1.Vdc DC=op1.Vdcnew
*** measurement for s12 and s22
*** measurement for s_1_2 and s_2_2
op
** second ac measurement (change this line only together with ac line above)
*ac lin 20 0.1G 2G $ use for bip transistor
ac lin 100 2.5MEG 250MEG $ use for Tschebyschef
*ac lin 101 1 10G $ use for RC
*ac lin 20 0.1G 2G ; use for bip transistor
ac lin 100 2.5MEG 250MEG ; use for Tschebyschef
*ac lin 101 1 10G ; use for RC
**
let s11=ac1.s22
let s21=ac1.s12
settype s-param S11 S21 S22 S12
let s_1_1=ac1.s_2_2
let s_2_1=ac1.s_1_2
settype s-param S_1_1 S_2_1 S_2_2 S_1_2
let S11db = db(s11)
let S12db = db(s12)
let S21db = db(s21)
let S22db = db(s22)
let S11db = db(s_1_1)
let S12db = db(s_1_2)
let S21db = db(s_2_1)
let S22db = db(s_2_2)
settype decibel S11db S21db S22db S12db
let P11=180*ph(s11)/pi
let P21=180*ph(s21)/pi
let P22=180*ph(S22)/pi
let P12=180*ph(S12)/pi
let P11=180*ph(s_1_1)/pi
let P21=180*ph(s_2_1)/pi
let P22=180*ph(S_2_2)/pi
let P12=180*ph(S_1_2)/pi
settype phase P11 P21 P22 P12
let Rbase=@R.X1.R4[Resistance]
settype impedance Rbase
*plot s11db s21db S22db S12db ylimit -50 0 xlog $ used with RC
plot s11db s21db S22db S12db ylimit -0.5 0 $ used with Tschebyschef
*plot s11db s21db S22db S12db ylimit -50 0 xlog ; used with RC
set xbrushwidth=2
plot s11db s21db S22db S12db ylimit -0.5 0 ; used with Tschebyschef
plot P11 P21 P22 P12
plot smithgrid S11 S12
*wrdata s3046 mag(S11) P11 mag(S21) P21 mag(S22) P22 mag(S12) P12 $ write simple table
wrs2p s3046.s2p $ write touchstone vers. 1 file s3046.s2p
plot smithgrid S_1_1 S_1_2
*wrdata s3046 mag(S_1_1) P11 mag(S_2_1) P21 mag(S_2_2) P22 mag(S_1_2) P12 ; write simple table
wrs2p $inputdir/s3046.s2p ; write touchstone vers. 1 file s3046.s2p
.endc
.end

10
src/frontend/postcoms.c
View File

@ -608,7 +608,7 @@ done:
with command wrs2p file .
Format info from http://www.eda.org/ibis/touchstone_ver2.0/touchstone_ver2_0.pdf
See example 13 on page 15: Two port, ASCII, real-imaginary
Check if S11, S21, S12, S22 and frequency vectors are available
Check if S_1_1, S_2_1, S_1_2, S_2_2 and frequency vectors are available
Check if vector Rbase is available
Call spar_write()
*/
@ -633,10 +633,10 @@ com_write_sparam(wordlist *wl)
/* generate wordlist with all vectors required*/
sbuf[0] = "frequency";
sbuf[1] = "S11";
sbuf[2] = "S21";
sbuf[3] = "S12";
sbuf[4] = "S22";
sbuf[1] = "S_1_1";
sbuf[2] = "S_2_1";
sbuf[3] = "S_1_2";
sbuf[4] = "S_2_2";
sbuf[5] = NULL;
wl_sparam = wl_build((const char * const *) sbuf);