Drive align filter has been implemented. The procedure is as follows:
- Measure the L2P/L2Y coupling without DRIVEALIGN. I measured the TF from the MNL to OLP and OLY.
- Roughly fit the TF as shown in the attachd figure. I did not care about Q factor finely. It is difficult to know how much it is, and it changes by the condition of the control, so it is not really usefull to know the exact Q.
- We know which is the resonance of the Y2Y. So remove it from L2P/L2Y coupling TF and use it as the DRIVEALIGN filter.
The result of the decoupling is shown in the attached figure. Red is the L2P./L2Y with the frequency dependent DRIVEALIGN, blue is the one with the frequency independent DRIVEALIGN, and the brown is the one without DRIVEALIGN.
- At whole frequency region, coupling has been improved by DRIVEALIGN. Especially around 1 Hz, the frequency dependent one reduce the L2P around 1 Hz.