vswr circles

Hi,

For the amplifier design in ADS,
how to plot constant VSWR circle
on Gamma-S and Gamma-out
plane?

Here, VSWRin for input port,
and VSWRout for output port.

Thanks a lot.

Best Regards,
Tony Tao

Hi,

Constant VSWR circles are actually constant gain circles. Device itself has gain that coresponds to Gmax at a given frequency. By chosing the gain smaller that Gmax (selecting a constant gain circle instead of a dot that corespond to Gmax) you are mismatching the device. The mismach is constant on a constant gain circle, so is the VSWR. You can derive a formula to know exactly what VSWR is on your chosen constant gain circle.

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