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Smith chart in Matlab?

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Frank Wiedmann

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Oct 11, 1995, 3:00:00 AM10/11/95
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Corbett Rowell (ph...@uxmail.ust.hk) wrote:
: Is there a function/m-file that draws a smith chart and then
: allows one to plots points/curves on?

Some time ago, I wrote a short function that draws a very simple Smith
chart. You can find it under the URL

ftp://ftp.mathworks.com/pub/contrib/graphics/smith.m

Regards,

Frank

Lars Erup

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Oct 11, 1995, 3:00:00 AM10/11/95
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ph...@uxmail.ust.hk (Corbett Rowell) wrote:
>Is there a function/m-file that draws a smith chart and then
>allows one to plots points/curves on?

I haven't seen one as such; the "polar" plot should help you get there.

--
Lars Erup | ESTEC D/TEL/TST
mailto:la...@t.estec.esa.nl | P.O. Box 299
Web: http://www.esrin.esa.it | NL-2200 AG The Netherlands
"On a clear disk, you can seek forever"


Corbett Rowell

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Oct 11, 1995, 3:00:00 AM10/11/95
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Is there a function/m-file that draws a smith chart and then
allows one to plots points/curves on?

Thanks,

-C

--
/>
/< Corbett Rowell
O[\\\\\\(O):::<===================================-
\< Hong Kong University of Science and Technology
\> ph...@ee.ust.hk

Soeren Laursen

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Oct 12, 1995, 3:00:00 AM10/12/95
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In article <45fe5j$e...@news.ust.hk>, ph...@uxmail.ust.hk (Corbett Rowell) writes:
> Is there a function/m-file that draws a smith chart and then
> allows one to plots points/curves on?

I have created some basic routines for this purpose. If you are interested, I
could mail them. If you need more sophiscated plotting routines than the ones
included I would be very interested to know - I would then implement these
in the package.

Thomas P. Krauss

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Oct 12, 1995, 3:00:00 AM10/12/95
to

Here is something from the MathWorks ftp site:
(/pub/contrib/graphics/smith.m)
------
function smith
% SMITH Draws a Smith chart and sets hold to on so that you can plot the
% reflection coefficient on top of it.

% This is a quick little hack that draws a simple Smith chart, a diagram
% that is very frequently used in high frequency engineering. It maps
% the normalized impedance z to the reflection coefficient gamma:
% gamma = (z-1)/(z+1) with z = r+i*x .

% You can customize the function by specifying the r=const and x=const lines
% you want to draw at the beginning of the corresponding loops.

% 3-13-95 Frank Wiedmann wied...@com.enst.fr


plot([-1 1],[0 0],'w')

axis equal
axis off

hold on

tr = 2*pi*(0:.01:1);
for r = [0 .2 .5 1 2 5] % specify the r=const lines you want to draw
rr = 1/(r+1);
cr = 1-rr;
plot(cr+rr*cos(tr),rr*sin(tr),'w')
end

for x = [.2 .5 1 2 5] % specify the x=const lines you want to draw
rx = 1/x;
cx = rx;
tx = 2*atan(x)*(0:.01:1);
plot(1-rx*sin(tx),cx-rx*cos(tx),'w')
plot(1-rx*sin(tx),-cx+rx*cos(tx),'w')
end
+=== Tom Krauss ========================= kra...@mathworks.com ===+
| "Eschew obfuscation." |
| The MathWorks, Inc. in...@mathworks.com |
| 24 Prime Park Way http://www.mathworks.com |
| Natick, MA 01760-1500 ftp.mathworks.com |
+=== Tel: 508-653-1415 ==== Fax: 508-653-2997 ====================+

khaniva...@gmail.com

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Apr 22, 2014, 1:05:12 AM4/22/14
to
On Wednesday, October 11, 1995 10:30:00 AM UTC+3:30, Frank Wiedmann wrote:
> Corbett Rowell (ph...@uxmail.ust.hk) wrote:
> : Is there a function/m-file that draws a smith chart and then
> : allows one to plots points/curves on?
>

khaniva...@gmail.com

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Apr 22, 2014, 1:07:35 AM4/22/14
to
On Wednesday, October 11, 1995 10:30:00 AM UTC+3:30, Corbett Rowell wrote:
> Is there a function/m-file that draws a smith chart and then
> allows one to plots points/curves on?
>
> Thanks,
>
> -C
>
> --
> />
> /< Corbett Rowell
> O[\\\\\\(O):::<===================================-
> \< Hong Kong University of Science and Technology
> \> ph...@ee.ust.hk

HELLO HOW ARE YOU ?PLAES SEND FOR ME SMITH CHART COD WITH MATLAB KHANIVA...@GMAIL.COM

Barry Williams

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Apr 22, 2014, 1:56:04 PM4/22/14
to
khaniva...@gmail.com wrote in message <7bfe37ea-0900-405e...@googlegroups.com>...
Are you expecting the original poster to respond to this? You do realize that this was posted almost 9 years ago?
Check the FE. There are a number of contributions there that may fit what you need.
Barry

Steven Lord

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Apr 22, 2014, 6:19:37 PM4/22/14
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"Barry Williams" <barry.r.wil...@saic.com> wrote in message
news:lj6afk$prf$1...@newscl01ah.mathworks.com...
> khaniva...@gmail.com wrote in message
> <7bfe37ea-0900-405e...@googlegroups.com>...
>> On Wednesday, October 11, 1995 10:30:00 AM UTC+3:30, Corbett Rowell
>> wrote:
>> > Is there a function/m-file that draws a smith chart and then allows one
>> > to plots points/curves on?
>> >
>> > Thanks,
>> >
>> > -C
>> >
>> > --
>> > />
>> > /< Corbett Rowell
>> > O[\\\\\\(O):::<===================================-
>> > \< Hong Kong University of Science and Technology
>> > \> ph...@ee.ust.hk
>>
>> HELLO HOW ARE YOU ?PLAES SEND FOR ME SMITH CHART COD WITH MATLAB
>> KHANIVA...@GMAIL.COM
>
> Are you expecting the original poster to respond to this? You do realize
> that this was posted almost 9 years ago?

From the date quoted, it's not 9 years ago. It's nearly nineteen.

> Check the FE. There are a number of contributions there that may fit what
> you need.

There's also a SMITHCHART function in RF Toolbox:

http://www.mathworks.com/help/rf/smithchart.html

--
Steve Lord
sl...@mathworks.com
To contact Technical Support use the Contact Us link on
http://www.mathworks.com

Barry Williams

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Apr 23, 2014, 6:35:11 AM4/23/14
to
*snip*
> > Are you expecting the original poster to respond to this? You do realize
> > that this was posted almost 9 years ago?
>
> From the date quoted, it's not 9 years ago. It's nearly nineteen.
>
> > Check the FE. There are a number of contributions there that may fit what
> > you need.
>
> There's also a SMITHCHART function in RF Toolbox:
>
> http://www.mathworks.com/help/rf/smithchart.html
>
> --
> Steve Lord
> sl...@mathworks.com
> To contact Technical Support use the Contact Us link on
> http://www.mathworks.com

A decade here, a decade there. Guess I lost track of time.
Barry

Frank Wiedmann

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May 3, 2014, 3:10:13 PM5/3/14
to
khaniva...@gmail.com wrote in message <75cb54cd-09fb-4a18...@googlegroups.com>...
The file smith.m is now available as a part of https://sites.google.com/site/frankwiedmann/publications/calibration.zip .

Regards,

Frank

Frank Wiedmann

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May 3, 2014, 3:16:11 PM5/3/14
to
"Barry Williams" <barry.r.wil...@saic.com> wrote in message <lj850v$gt8$1...@newscl01ah.mathworks.com>...
The very simple Smith Chart function I wrote 19 years ago is available as smith.m in https://sites.google.com/site/frankwiedmann/publications/calibration.zip .

Regards,

Frank

Frank Wiedmann

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May 3, 2014, 3:42:11 PM5/3/14
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"Frank Wiedmann" wrote in message <lk3euk$kd2$1...@newscl01ah.mathworks.com>...
I just noticed that the file content is also available at https://groups.google.com/d/msg/comp.soft-sys.matlab/7AQDdtUHxiE/rf-wPyn-YqoJ

Regards,

Frank

Frank Wiedmann

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May 3, 2014, 3:47:11 PM5/3/14
to
> The very simple Smith Chart function I wrote 19 years ago is available as smith.m in https://sites.google.com/site/frankwiedmann/publications/calibration.zip .

I just noticed that the function text is also still available in the old thread at https://groups.google.com/d/msg/comp.soft-sys.matlab/7AQDdtUHxiE/rf-wPyn-YqoJ

Regards,

Frank

corbett...@nu.edu.kz

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Nov 17, 2014, 6:49:15 PM11/17/14
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This is the original poster. One of my undergraduate students spotted this thread for a Smith Chart in Matlab lab--brings back the good ole memories of Usenet.

Since that question was posed 19 years ago, I have made substantial use of various Smith Chart functions and code in Matlab throughout my career; very belated thanks to Frank and Thomas for their help.

/>
/< Corbett Rowell
O[\\\\\\(O):::<===================================-
\< Nazarbayev University
\>

Frank Wiedmann

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Nov 18, 2014, 7:23:17 AM11/18/14
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Hi Corbett,

Nice to meet you again after all those years. I am glad that I was able to help you. Yes, those were the days of Usenet, email servers, anonymous ftp, telnet and the newfangled Mosaic browser (as documented in appendix A of my diploma thesis http://scholar.google.de/citations?view_op=view_citation&hl=en&citation_for_view=JcAIYHEAAAAJ:_FxGoFyzp5QC ).

Regards,

Frank
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