Terminator3
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Drain stub electrical length = 180+Angle(s11)/2. Actually it is the same as matching phase in this way: Gs=1/S11
Gate stub electrical length = 180+Angle(s22)/2 - Angle(S21). It is more interesting, it gives me exact stub length matched with the photo of of microstrip oscillator in few papers. While using Gout=S22+(Gs*S12*S21)/(1-S11*Gs) and Gload=1/Gout gived less acurate results.
For example, from push-push oscillator:
i guessed almost exact stub lengths of 103.5deg and 80deg, while using "bookish" approach we have right value for gate, but wrong guess for drain:
of 89deg electrical length for drain, more 10degs.
In another design similar results, bookish drain lenght three times longer than the real drain stub on the photo. But when using 180+Angle(s22)/2 - Angle(S21) for guessing all is precise to 1deg. So where it comes from?
Gate stub electrical length = 180+Angle(s22)/2 - Angle(S21). It is more interesting, it gives me exact stub length matched with the photo of of microstrip oscillator in few papers. While using Gout=S22+(Gs*S12*S21)/(1-S11*Gs) and Gload=1/Gout gived less acurate results.
For example, from push-push oscillator:
Code:
35.8/4
Ans = 8.95e0
wavelen=82*4
wavelen = 3.28e2
gate_photo=360*94/wavelen
gate_photo = 1.031707317e2
drain_photo=360*74/wavelen
drain_photo = 8.12195122e1
gate_guess=-153/2+180
gate_guess = 1.035e2
drain1=-136/2+180
drain1 = 1.12e2
drain_guess=drain1-32
drain_guess = 8e1
Code:
OpenStub=ATan(-i*50/Zload)
OpenStub = 8.917401688e1In another design similar results, bookish drain lenght three times longer than the real drain stub on the photo. But when using 180+Angle(s22)/2 - Angle(S21) for guessing all is precise to 1deg. So where it comes from?