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So i was reading Anant Agarwal's book Foundation of Circuits and stumble upon this postulate

"Operate in the regime in which signal timescales of interest are much larger than the propagation delay of electromagnetic waves across the lumped elements"

"The signal timescales must be much larger than the propagation delay of electromagnetic waves through the circuit."

Why is that the signal timescale be so much larger than the propagation delay of electromagnetic waves? I dont get the consequences if we are to bypass this limitation. Thank you

MarkU
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vvavepacket
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  • In case you'd like to check out prof. Agarwal's lecture on this topic: [Lec 25 | MIT 6.002 | Violating the abstraction barrier](http://www.youtube.com/watch?v=dyxcCoUgETU) – DimKo Jul 05 '12 at 12:03

1 Answers1

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At high frequencies, you need to model connections between elements with a transmission line as there are delays associated with the interconnects. This is what you are referring to. At low frequencies, these delays are negligible to the operation of the circuit as a whole as they act at very small timescales, but at higher frequencies the behaviour of the circuit needs to take these delays into account as they cause reflections and unexpected noise into the circuit if it is not designed properly.

For more information check out wikipedia's article on Transmission lines

slurms
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