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    Reflections when conjugately matched

    Hi, as per Pozar's Microwave Engineering book, there is a condition
    "A special case of the transducer power gain occurs when both the input and output are matched for zero reflection (in contrast to conjugate matching). Then GammaL = GammaS = 0" then GT=S21^2.
    And another one is conjugate matched condition.
    Does this mean ever after performing conjugate matching, there will be still reflections?. Could someone explain the difference between these two conditions.

    Thanks in advance.

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    Re: Reflections when conjugately matched

    Quote Originally Posted by circuitslave View Post
    Does this mean ever after performing conjugate matching, there will be still reflections?.
    Voltage wave is reflected.

    Quote Originally Posted by circuitslave View Post
    Could someone explain the difference between these two conditions.
    Surely read and learn Power wave in Pozar’s Book, before EDA Tool Play.

    See the followings.
    https://www.edaboard.com/showthread.php?378353#5
    https://www.edaboard.com/showthread.php?378353#20
    Last edited by pancho_hideboo; 8th November 2019 at 00:54.


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    Re: Reflections when conjugately matched

    Quote Originally Posted by circuitking View Post
    Hi, as per Pozar's Microwave Engineering book, there is a condition
    "A special case of the transducer power gain occurs when both the input and output are matched for zero reflection (in contrast to conjugate matching). Then GammaL = GammaS = 0" then GT=S21^2.
    And another one is conjugate matched condition.
    Does this mean ever after performing conjugate matching, there will be still reflections?. Could someone explain the difference between these two conditions.

    Thanks in advance.
    There's a subtle distinction between travelling waves (aka voltage waves) and power waves. For travelling waves, the reflection coefficient is defined as Gamma=(ZL-Zs)/(ZL+Zs). For power waves, Gamma=(ZL-Zs*)/(ZL+Zs). So for a conjugate match, the power wave reflection coefficient will be zero, but the travelling wave reflection might not be.


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    Re: Reflections when conjugately matched

    Researched in my literature and found very intuitive explanation about Power Waves and Scattering
    "Microwave Transistor Amplifiers-Analysis and Design"-Guillermo Gonzalez Section 1.7 pp:45-60



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