Interference mitigation using a focal plane array
Article first published online: 25 JUN 2005
Copyright 2005 by the American Geophysical Union.
Volume 40, Issue 5, October 2005
How to Cite
2005), Interference mitigation using a focal plane array, Radio Sci., 40, RS5S16, doi:10.1029/2004RS003138., , , , and (
- Issue published online: 25 JUN 2005
- Article first published online: 25 JUN 2005
- Manuscript Accepted: 23 MAR 2005
- Manuscript Revised: 16 MAR 2005
- Manuscript Received: 26 JUL 2004
- radio astronomy;
- RFI mitigation;
- array feeds
 We consider the use of spatial filtering algorithms for radio frequency interference (RFI) mitigation in conjunction with a focal plane feed array of electrically small elements. Numerical simulations are used to study the performance of 7 and 19 element hexagonal dipole arrays with a 25 m reflector at an operating frequency of 1612 MHz. Using the maximum SNR algorithm to generate array weights, an interfering signal was attenuated by 40 dB or more. The effective sensitivity of the system, including interferer power in the system noise temperature, was comparable to the sensitivity attained in the absence of RFI. Moving the interferer through the reflector pattern sidelobes caused fluctuations in the gain and system sensitivity. This effect was exacerbated by a reflector model with random surface distortions. These results indicate that array feeds are a promising approach for RFI mitigation, but achieving stable radiation patterns in the presence of an interferer may require a trade-off between pattern control and maximum attainable sensitivity.