Adaptive Noise Cancellation: A Panacea

1. Adaptive Noise Cancellation:A Panacea • Evans, R. Adhikari

2. The Concept • 5000 Channels • 1 GW Channel • Signal = DARM - noise

3. Wiener Filter Norbert Wiener, MIT Block Toeplitz Cross Correlation Matrix Input Signal (PEM) Covariance Matrix

4. Wiener Filter Sim H1 L1 • H1 & L1 DARM (S5) • All Guralp & STS2 • Vault not used • Requires ~9 GB RAM • Levinson-Durbin x10 x7

5. Adaptive Filtering /Neural Network Keenan Pepper Elena Gasparri LMS Algorithm (1st chapter of textbooks)

6. ATNF

7. Filtered-X LMS Edwards, Thesis (declassified) Naval Research Postgraduate School

8. Applications • Seismic Noise (0 - 40 Hz) • Upconversion • Lock Acquisition • Bilinear (Crab shoulder) • Acoustic Noise (50-900 Hz) • Magnetic (power lines) • H1/H2 correlation • MICH/PRC/SRC

9. From LMS to Filtered-X Noisy Signal • LMS Noise Witness FIR Cleaner Signal Adapt

10. From LMS to Filtered-X Total Control Signal • Injecting into a high gain servo loop Noise Witness FIR G Servo Control Signal Adapt

11. From LMS to Filtered-X Total Control Signal • Separated Actuators • Special case of “Filtered X-LMS” Noise Witness FIR A2 G A1 Servo Control Signal Adapt C

12. At the 40m MC Length • Test on input mode-cleaner Seismic Sensors FIR MC1 G MC2 MC_L Adapt C

13. At the 40m

14. At the 40m

15. And more !