Using the Gate Utility to Simplify
Note that Option 107 is required to perform this application
The time gate allows the user to control when a spectrum analyzer measurement begins and the length of time during which the measurement is made. The time gate is an RF signal switch that permits signal into the spectrum analyzer only while the switch, or gate, is closed. Since the spectrum analyzer receives the signal only when passed through the gate, it will only display the measurement results from the portion of the signal selected by the time position of the gate closure. The time gate acts as a time filter, rejecting signals and spectra not occurring at the desired time.
The time gate utility simplifies the use of the time gate. In the gate utility, the spectrum analyzer can display the time domain and the frequency domain simultaneously, using two separate windows. The user is able to adjust the time position of the gate closure relative to the input signal, using interactive graphic tools in the gate utility. The gate position relative to the signal is clearly shown in the time domain window. The spectral effects corresponding to an adjustment of the gate time position are displayed in the frequency domain window. Tools are provided to aid the user in determining the best gate position, and optimizing the spectrum analyzer settings for the input signal.
CENTER | 9BB.BBB | RHz | SPAN B HZ |
YRES BW | 1.B MHz | WUBW 1 MHz | YSWP |
I________ | ____ |
| ....... |
| ||||
| 900 | MHz |
| SPAN | 1.800 | &Hz | L | |
RES BW | 3.0 | NHz | VBW 1 MHz | #SWP | 36.8 | msec | ||
| ||||||||
Figure 5-15. Time-Gate Utility Display
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