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This paper describes methods for accurate pattern modeling of large axisymmetric paraboloidal focus-fed reflector antenna systems. We demonstrate that the incorporation of the developed pattern models helps in advancing the state-of-the-art in coherent time-domain canceling (CTC) for interference mitigation in radio astronomy. The first method yields a closed form expression for the antenna pattern with parameters accounting for the focal ratio and feed pattern. In subsequent adaptive methods, parameters of this model are calculated using measurements of interference signals. The corrected pattern model improves the prediction of the change in the true pattern for future times. The methods are compared by (1) comparing the error in the pattern model with respect to the true pattern and (2) comparing the pattern value update period required to achieve a specified level of residual interference when used in CTC. The efficacy of the pattern modeling methods is demonstrated by showing that the error in the pattern model decreases and the pattern value needs to be updated at a much slower rate for effective CTC.
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Effect of Antenna Pattern on Time-Domain Canceling of Interference from Satellites
Signals from satellites are a source of interference to radio telescopes. One possible scheme for mitigation of this interference is coherent time-domain canceling. Using a simple but broadly-applicable model for the antenna pattern, we show how the antenna pattern combined with the motion of the satellite limits the time available to compute an accurate estimate of the interference waveform, which subsequently limits the extent to which interference can be canceled in the output. We suggest a simple remedy to the problem.
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- Award ID(s):
- 2029948
- PAR ID:
- 10534942
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 978-1-6654-4228-2
- Page Range / eLocation ID:
- 1131 to 1132
- Format(s):
- Medium: X
- Location:
- Portland, OR, USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/USNC-URSI52151.2023.10237408
