Ceyear 4051 Series, User Manual

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5 Menu
5.2. Description of menu
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goes TRUE again. But since the LO is sweeping as long as the gate conditions are satisfied, the sweep
typically finishes much more quickly than with Gated Video.
When in zero span, there is no actual sweep performed. But data is only taken while the gate conditions are
satisfied. So even though there is no sweep, the gate settings will still function when data is acquired.
●
Key path: 【 Sweep 】 , [Gate ▶ ], [Gate Setup ▶ ], [Gate Method ▶ ], [LO] on the front panel.
● Remote Command:
[:sense]:sweep:egate:method LO
[:sense]:sweep:egate:method?
● Examples:
:SWE:EGAT:METH LO
:SWE:EGAT:METH?
[Video]
● Menu description: to set the gate method as Video.
This form of gating may be thought of as a simple switch, which connects the input signal to the
signal/spectrum analyzer. When the switch is ON (Gate ON), the video signal is allowed to pass through; and
the switch is off (Gate OFF), the signal is blocked. Under Gated Video, whether the gate is ON or OFF, the
signal/spectrum analyzer measures signals and never stops sweeping. The Gate Switch is between the signal
pathway envelope detector and video filter, therefore is called as Gated Video. Since the Gate Switch is
behind the envelope detector, whether the Gate is on or off, the signal/spectrum analyzer measurement path
will respond to the input signal; therefore, it is necessary to reduce the sweep speed to the extent that the
signal/spectrum analyzer can measure input signal during Gate ON period, which results in certain limits for
applying Gated Video measurements. For this reason, in general, Video method results in slower measurement
compared with Gated LO and FFT.
●
Key path: 【 Sweep 】 , [Gate ▶ ], [Gate Setup ▶ ], [Gate Method ▶ ], [Video] on the front panel.
● Remote Command:
[:sense]:sweep:egate:method video
[:sense]:sweep:egate:method?
● Examples:
:SWE:EGAT:METH VID
:SWE:EGAT:METH?
[FFT]
●
Menu description: to the gate method as Gated FFT.
The way of FFT spectrum measurement if the trigger conditions are satisfied, which is called as the gated FFT.
The FFT spectrum is the input signal spectrum through FFT calculation from a time domain waveform during
collection. The time for collecting the domain waveform is similar to the gate length. The time for collecting
the domain waveform is similar to the gate length. Different from the Sweep Time Gate, under Gated FFT, the
gate length is determined by the currently set resolution bandwidth and cannot be set and modified through
menu. When the Span is less than 10 MHz, in particular for small resolution bandwidth, the FFT measurement
is faster than the Sweep measurement; therefore, for a given signal period, compared with Gated LO, the
Gated FFT gets higher frequency resolution.