40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Message ID: 10266     Entry time: Wed Jul 23 19:30:34 2014
Author: Nichin 
Type: Update 
Category: Electronics 
Subject: Time delay in the RF multiplexer (Rack 1Y1) 

A time delay can be modeled as the exponential transfer function :  e(-sTd)  as seen HERE . Therefore the slope of the phase gives us the time delay.

The transfer function of RF multiplexer in rack 1Y1 (NI PXI-2547) was fit to an ideal delay function e(-sTd) , with Td = 59 ns.

The plots shows the actual data, fit data and data after correction using the ideal model stated above.

Conclusion:

Delay the RF Multiplexer is approximately 59 ns. This value can be used to correct the phase in measurements of transimpedance for each PD by dividing out the ideal transfer function for time delay.

 

Attachment 1: RFmux1.pdf  7 kB  | Hide | Hide all
RFmux1.pdf
Attachment 2: RFmux2.pdf  6 kB  | Hide | Hide all
RFmux2.pdf
ELOG V3.1.3-