what is the alternative method for time domain reflectometry

Thread Starter

yef smith

Joined Aug 2, 2020
Hello, i have read that TDR is problemtaic because if we have many transmission lines in series which cause didcontnuety to the sourse resistanse then the closer TL's will mask the reading of the far TL from the source,so is when the rise time of the source is larger the TL delay.
So what is the alternative to the TDR? what mehtod is used to overcome those problems and see the impedance at every location of the system?
An example is shown in the link bellow
we have 80,30 ,50 TL's and 80,30 create masking problem for reading the 50ohm TL
Last edited:


Joined Feb 29, 2020
The reference cited above is very good and explains the limitations of TDR pretty well. Its basically limited by physics and noise- engineering tradeoffs. VNA techniques using frequency domain techniques and then transposing to time domain is the main alternative but it has similar limitations imposed by SNR and attenuation over the medium. Its an area that might be ripe for some research but ultimately it comes down to classic EE tradeoffs of SNR, Dynamic Range and noise.