Connect with us

high reflection coefficient and phase shift

Discussion in 'Electronic Basics' started by tsp, Feb 21, 2004.

Scroll to continue with content
  1. tsp

    tsp Guest

    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
     
  2. Gareth

    Gareth Guest

    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.

    --
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-