Hi,
Can somebody explain, how a high reflection coefficient is related to phase shift? Some of the book I have been reading on LNAs say that as long as we have a high reflection coefficient we can phase shift and transform a 50 ohm impedance to short circuit. How does this happen? How would it work if I was to look at a Smith Chart?
Thanks, tsp
A high reflection coefficient means a point near the edge of the Smith chart, a phase shift can move that point round the edge of the chart, so you can get to a short circuit (or open circuit if you wanted) with the appropriate phase shift.
Another way of looking at it is that you choose a phase shift such that the reflected wave arrives 180 degrees out of phase with the original wave, so the voltage cancels and you get zero volts as you would with a genuine short circuit.
Gareth.
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