smith chart need help

[ericyeoh]

Hi all,

I'm new to smith chart, i would like to know how to draw gain circle and noise circle on Z-Y smith chart.
Here is the data i got
For noise :
Centre of noise circle = 0.11<-145 deg, Radius of noise circle = 0.2847
Centre of gain circle = 0.44 < -149 deg, Radius of gain circle = 0.3875

 

[young.microwave.eng]

Dear eric
firstly there are lots of softwares that do your job very simple.
see link bellow for software(smith chart tool)
and for gain and noise figure circle you have the magnitude and phase available
smith chart is a complex plane.you know for complex planes having these two parameters you can indicate a point in that
so using compass and conveyor you can find it

---------- Post added at 06:06 ---------- Previous post was at 06:06 ----------

link:
https://www.edaboard.com/threads/6045/

 

[goal]

if you want to draw manually.for noise figure circle draw line from centre of chart to the angle -145 degrees on "angle of reflection co-eff" circle.
take 0.11 measurement with a compass or divider from the scale marked as "reflectin co-eff E/I" at the bottom of smith chart. mark this measurement from centre of chart on the line which is drawn at -145deg, this point is the centre. similarly take 0.2847 measurement also from the refelection co-eff E/I scale with compass, use centre as 0.11 and draw the noise figure circle.