K. Venkateswara
I've attached ASD and coherence plots from 40k seconds of data from BRS/T240 and the super sensor from last night. Wind speeds were in the 5-10 mph range. This time, I showed the raw signals coming out from BRS and the T240 X instead of showing the output of the filters. I've also shown the ref. mirror and the output of the super-sensor.
BRS has much larger noise below 2-3 mHz, than the T240, even though the sensor noise appears to be much less. It was interesting to me that it had a similar shape as the ref. mirror output and there does appear to be some coherence between the two. Temperature is the usual suspect at these frequencies. A sensitive temperature sensor on the BRS platform would be useful in diagnosing this noise.