A5031392979- Radio Astronomy Observations and Technology
- Advanced Wireless Communication Techniques
- GNSS positioning and interference
- Astrophysics and Cosmic Phenomena
- Soil Moisture and Remote Sensing
- Antenna Design and Optimization
- Radio Wave Propagation Studies
- Satellite Communication Systems
- Millimeter-Wave Propagation and Modeling
- Precipitation Measurement and Analysis
University of Cambridge
2023-2025
We detail the REACH radiometric system designed to enable measurements of 21-cm neutral hydrogen line. Included is radiometer architecture and end-to-end simulations as well a discussion challenges intrinsic highly-calibratable development. Following this, we share laboratory results based on calculation noise wave parameters utilising an over-constrained least squares approach. For five hours integration custom-made source with comparable impedance that antenna used in field, demonstrate...
Interfering signals such as radio frequency interference from ubiquitous satellite constellations are becoming an endemic problem in fields involving physical observations of the electromagnetic spectrum. To address this we propose a novel data cleaning methodology. Contamination is simultaneously flagged and managed at likelihood level. It modeled Bayesian fashion through piecewise that constrained by Bernoulli prior distribution. The techniques described paper can be implemented with just...
We detail the REACH radiometric system designed to enable measurements of 21-cm neutral hydrogen line. Included is radiometer architecture and end-to-end simulations as well a discussion challenges intrinsic highly-calibratable development. Following this, we share laboratory results based on calculation noise wave parameters utilising an over-constrained least squares approach demonstrating calibration RMSE 80 mK for five hours integration custom-made source with comparable impedance that...
Abstract Contamination by radio frequency interference (RFI) is a ubiquitous challenge for astronomy. In particular, transient RFI difficult to detect and avoid, especially in large data sets with many time bins. this work, we present Bayesian methodology time-dependent, anomaly mitigation performed jointly model fitting. The computation correcting anomalies manner time-separated grows proportionally the number of We demonstrate that utilizing likelihood reweighting can allow our method be...
Due to the large dynamic ranges involved with separating cosmological 21-cm signal from Cosmic Dawn galactic foregrounds, a well-calibrated instrument is essential avoid biases instrumental systematics. In this paper we present three methods for calibrating global cosmology experiment using noise wave parameter formalisation characterise low amplifier including careful consideration of how calibrator temperature and singularities will bias result. The first method presented in builds upon...
Interfering signals such as Radio Frequency Interference from ubiquitous satellite constellations are becoming an endemic problem in fields involving physical observations of the electromagnetic spectrum. To address this we propose a novel data cleaning methodology. Contamination is simultaneously flagged and managed at likelihood level. It modeled Bayesian fashion through piecewise that constrained by Bernoulli prior distribution. The techniques described paper can be implemented with just...
Contamination by Radio Frequency Interference (RFI) is a ubiquitous challenge for radio astronomy. In particular, transient RFI difficult to detect and avoid, especially in large data sets with many time bins. this work, we present Bayesian methodology time-dependent, anomaly mitigation. general, the computation correcting anomalies time-separated grows proportionally number of We demonstrate that utilising likelihood reweighting can allow our mitigation method be performed close independent...