Time Gating Parameters (Time Gating)

The following parameters are used by time-gated measurements.

Gate check box
Gate Delay
Gate Length
Gate Window Type
Main Time Length
Trigger Parameters

Click MeasSetup > Time to view all time gating parameters as well as the Main Time Length parameter. Click Input > Trigger to view the trigger parameters.

Time gating is only available with the Vector and Analog Demod measurement types.

The duration of the main time-record collected by the measurement hardware is defined by Main Time Length, and the position of the main time-record relative to the trigger is defined by the trigger delay. After the main time- record has been acquired, the VSA isolates a portion of the data as the gate record. The duration and position of the time gate, relative to the start of the main record, are determined by the gate Length and gate Delay, respectively.

Trigger Parameters determine when the measurement hardware takes data for the main time-record.

Main Time Length determines the length of the main time-record. If your measurement hardware has multiple input channels, Main Time Length sets the length of the main time-record for all input channels.

Gate check box selects time gating.

Gate > Delay determines the start of the gate time-record within the main time-record. A gate delay of zero places the start of the gate time-record at the beginning of the main time-record.

You can specify a single Delay for all logical input channels or you can set Delay for each channel individually. To set Delay for a specific channel, click the triangle button to the right of the delay field and choose a channel.

Gate > Length determines the length of the gate time-record for all input channels.

Gate > Window Type specifies the window to use for gated spectral displays. By default, the VSA uses the same window for gated spectrums that it uses for non-gated spectrums. However, Gate > Window Type can be used to choose a different window for gated spectrums.

Use the MeasSetup > ResBW > Window Type parameter to set the window for non-gated spectral displays.

Gate > Same as Main check box, when selected, locks the window type for gated spectra to match the window used for the main time record. In other words, changing the windowing function for the main time record also changes the windowing function for the gate time record.

Changing the gated windowing function automatically clears the Gate > Same as Main check box.