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1

The distributed L and C are commonly held to start acting like a transmission line at lengths of 1/10th wavelength or so. But this is gradual, not a sudden onset at that length. Although the inductance may depend more on the length, parasitic capacitance effects can occur at much shorter sizes. In digital circuits, capacitive noise coupling between traces ...


4

The general rule of thumb is anything more than 1/10th the wavelength should be considered a transmission line. At 446 MHz, that's 67 mm. Your circuit is much smaller than that, so there's not much point in worrying about the trace impedance. Furthermore, everything right of the rectifier is DC. So moving the diode to be as close to possible to the RF ...


-1

TECHNICALLY NEVER WILL 100% OF YOUR POWER BE RADIATED, AND CONVERSELY WILL IT BE RE-REFLECTED BY / FROM ITS SOURCE. IN EITHER SITUATION, YOU WOULD HAVE THE EQUIVALENT OF PERPETUAL MOTION OR 100% EFFICIENCY. BOTH OF THE LATTER DO NOT EXIST. THAT IS ONE ANSWER TO YOUR QUESTION. NEXT IS THE OFT UTTERED, FALSE IDEA THAT A HIGH SWR WILL REFLECT POWER BACK INTO ...


4

The $SWR$ is, in principle, defined as a ratio of maximum and minimum voltages that exist at different locations of the transmission line. These two different voltages $U_{max}$ and $U_{min}$ can be measured to determine $SWR$. - However, $SWR$ can also be determined by the absolute value of the reflection coefficient, $|\Gamma |$, according to $$SWR = \frac{...


2

The source resistor will dissipate the vector sum of what can be modeled as the forward and reverse currents. Thus, for a pure sinusoid in steady state, if the forward and reverse currents are equal in magnitude but 180 degrees out of phase, they will vector sum to zero, which leads to the resistor dissipating zero power. Linear time invariant systems are ...


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