Spectrum Bandwidth 6dB Limits

[Noob_intern]

Equipment: E4440A Spectrum Analyzer 

Software: Labview, required driver all downloaded already 

Connection: GPIB-USB-HS

• So my objective is to write a labview program to auto do setting on this equipment, where values like Span, Res BW, VBW and Sweep are constant.
• The only 2 controls at front panel are Center Freq and Ref Lvl. 
• After the wavefrom is produced, my labview program will capture a screenshot and save in my PC.

the photo below is the steps:

➡️➡️➡️➡️➡️ So what i need help is: part (g) ⬅️⬅️⬅️⬅️⬅️

How do i get the peak value. 

Use the peak value minus by 6 = X

Then, use X to draw a straight horizontal limit line 

Find the 2 intersection point of the waveform and the limit line.  

inside LABVIEW*******

Thank you friend from all around the World 

Guy w 1 month experience of labview 

8Jan2022

[Noob_intern]