Adaptive filters revisited: Radio frequency interference mitigation in pulsar observations
Article first published online: 24 MAY 2005
Copyright 2005 by the American Geophysical Union.
Volume 40, Issue 5, October 2005
How to Cite
2005), Adaptive filters revisited: Radio frequency interference mitigation in pulsar observations, Radio Sci., 40, RS5S06, doi:10.1029/2004RS003136., , , , , and (
- Issue published online: 24 MAY 2005
- Article first published online: 24 MAY 2005
- Manuscript Accepted: 21 DEC 2004
- Manuscript Revised: 16 NOV 2004
- Manuscript Received: 28 JUL 2004
- RFI mitigation;
- adaptive filter
 Pulsar detection and timing experiments are applications where adaptive filters seem eminently suitable tools for radio frequency interference (RFI) mitigation. We describe a novel variant which works well in field trials of pulsar observations centered on an observing frequency of 675 MHz and a bandwidth of 64 MHz and with 2-bit sampling. Adaptive filters have generally received bad press for RFI mitigation in radio astronomical observations with their most serious drawback being a spectral echo of the RFI embedded in the filtered signals. Pulsar observations are intrinsically less sensitive to this as they operate in the (pulsar period) time domain. The field trials have allowed us to identify those issues which limit the effectiveness of the adaptive filter. We conclude that adaptive filters can significantly improve pulsar observations in the presence of RFI.