Howtosignalprocessing
- How is TDR measured?
- What is TDR and VNA?
- How is TDR impedance measured?
- What can a VNA measure?
- What is a TDR meter?
How is TDR measured?
The formula for determining this is: l = t x v/2, where l is length, t is time and v is velocity. The TDR instrument measures the time it takes for the pulse to return. If the exact length of cable is known, then the formula can be used to determine the propagation velocity.
What is TDR and VNA?
Two basic measurement techniques exist for signal integrity characterization of gigabit interconnects in digital systems - Time Domain Reflectometry (TDR) and frequency domain Vector Network Analysis (VNA). The TDR instrument is a very wide bandwidth equiva- lent sampling oscilloscope with an internal step gener- ator.
How is TDR impedance measured?
TDR feeds a pulse onto the transmission line on a test coupon. Then it measures the characteristic impedance by analyzing the changes in the amplitude of the reflected waveform. Note that TDR will only observe the reflections if the injected pulse experiences any discontinuity in its path.
What can a VNA measure?
A VNA measures the power of a high-speed signal going into and coming back from a component or a network, because power, in contrast to voltage and current, can be measured accurately at high frequencies. Both amplitude and phase of the high-frequency signal are captured at each frequency point.
What is a TDR meter?
Time domain reflectometers (TDR) are test devices that generate an energy pulse or step on the cable to determine the location and magnitude of cable faults, breaks, splices, terminations, or other events along the length of a conductive cable.
