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Matching with open-circuit stub

We try to match the input of the amplifier with a text_wrap_inline3319 from a 50 text_wrap_inline2807 termination.

The matching network design procedures

  1. Locate normalised admittance for text_wrap_inline3319 on the Smith chart as point text_wrap_inline3459. Since text_wrap_inline3479. The normalised admittance text_wrap_inline3459 should be at text_wrap_inline3483.
  2. With a section of 50 text_wrap_inline2807 line, convert the admittance until it has unity normalised conductance, point A as the Figure shown, i.e. Transfer the admittance, toward the source, until it meets the unity conductance circle.
  3. Add a parallel open-circuit stub section to provide the required susceptive part, i.e., Transfer from open-circuit to point B, toward the generator.

Figure 21: Input matching design with the aid of Smith chart

Figure 22: Complete circuit layout

With text_wrap_inline3405, text_wrap_inline2977, text_wrap_inline2965. The unilateral transducer power is text_wrap_inline3493. We can compare this gain with the case where the input and output are conjugately matched, i.e., text_wrap_inline2975 and text_wrap_inline2977.
Note that the difference is very small.