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1	Real-time adaptive cancellation of satellite interference in radio astronomy / Poulsen, Andrew Joseph. January 2003 (has links) (PDF) Thesis (M.S.)--Brigham Young University. Dept. of Electrical and Computer Engineering, 2003. / Includes bibliographical references (p. 377-382).
2	Active Impedance Matching and Sensitivity Optimized Phased Array Feed Design For Radio Astronomy Carter, David E. 24 August 2011 (has links) (PDF) One of the many challenges in radio astronomy is the ability to make accurate measurements quickly. In recent years engineers and astronomers have begun implementing phased array feeds (PAFs) as a way to negate the long observation times required by single antenna feeds. Unfortunately, large mutual coupling and other loss terms result in low sensitivity, restricting PAF usefulness in on dish observation. This thesis addresses several ways to reduce mutual coupling and maximize sensitivity for PAFs in radio astronomy. Antenna design of this magnitude requires accurate modeling capabilities. To this end, electromagnetic software models and low loss component designs are verified and validated with measured data. This process required the construction of a 50 Ω matched dipole and measurements on a network analyzer at Brigham Young University. The design and optimization of several single and dual polarization hexagonal grid arrays of 19 and 38 elements respectively are also described. Model figures of merit are compared with measurements taken on the 20-Meter dish at the National Radio Astronomy Observatory (NRAO) in Green Bank, WV and the 300 meter dish at the Arecibo Observatory in Arecibo, PR. Although some unexplained discrepancies exist between measured and model datasets, the dual pol cryocooled kite array described boasts the highest PAF sensitivity ever measured. Karl Jansky National Radio Astronomy Observatory Arecibo Observatory phased array feed active impedances beamforming Electrical and Computer Engineering
3	A social and political history of the National Radio Astronomy Observatory at Green Bank, WV Kenwolf, Lenora G. January 1900 (has links) Thesis (M.A.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains v, 78 p. Includes abstract. Includes bibliographical references (p. 64-78).
4	Real-time Adaptive Cancellation of Satellite Interference in Radio Astronomy Poulsen, Andrew Joseph 17 July 2003 (has links) (PDF) Radio astronomy is the science of observing the heavens at radio frequencies, from a few kHz to approximately 300 GHz. In recent years, radio astronomy has faced a growing interference problem as radio frequency (RF) bandwidth has become an increasingly scarce commodity. A programmable real-time DSP least-mean-square interference canceller was developed and demonstrated as a successful method of excising satellite down-link signals from both an experimental platform at BYU, and the Green Bank Telescope at the National Radio Astronomy Observatory in West Virginia. A performance analysis of this cancellation system in the radio astronomy radio frequency interference (RFI) mitigation regime constitutes the main contribution of this thesis. The real-time BYU test platform consists of small radio telescopes, low noise RF receivers, and a state-of-the-art DSP platform. This programmable real-time radio astronomy RFI mitigation tool is the first of its kind. Basic tools needed for radio astronomy observations and the analysis and implementation of interference mitigation algorithms were also implemented in the DSP platform, including a power spectral density estimator, a beamformer, and an array signal correlator. real-time radio astronomy interference DSP least-mean-square LMS satellite Green Bank Telescope GBT NRAO National Radio Astronomy Observatory RFI radio frequency interference telescope RF radio frequency mitigation power spectral density PSD beamformer correlator Very Small Array VSA antenna software OH sources hydroxyl algorithm spectral analysis GLONASS red-shifted Green Bank Electrical and Computer Engineering

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