Using time domain, data from transmission or reflection measurements in the frequency domain are converted to the time domain. The time-domain response shows the measured parameter value versus time.

Time Stimulus Modes

• Low-pass step
• This stimulus, similar to a traditional time domain reflectometer (TDR) stimulus waveform, is used to measure low-pass devices. The frequency-domain data should extend from DC (extrapolated value) to a higher value
• Low-pass impulse
• This stimulus is also used to measure low-pass devices
• Bandpass impulse
• The bandpass impulse stimulates a pulsed RF signal and is used to measure the time-domain response of band-limited devices

The windowing function can be used to filter the frequency-domain data and thereby reduce overshoot and ringing in the time-domain response.

Gating

The gating function can be used to selectively remove reflection or transmission time domain responses. In converting back to the frequency domain the effects of the responses outside the gate are removed.