This repository condenses the work that I've done on topics involving radio frequency interference and other astronomy topics during my undergraduate years and in my post-graduation internship.
These files are taken from my larger berkeley repository at https://github.com/rgao/berkeley.
Identifying radio frequency interference is central to most work involving radio astronomy. Due to the proliferation of radio technology in this digital era, radio sources from Earth (along with some of extraterrestrial origins) must be filtered as noise before work is done to detect target extraordinary signals.
These Jupyter Notebooks are produced during my internship at Breakthrough Listen. They serve as tutorials for future interns who engage in the basics of scientific computing and radio frequency interference.
The sdr_stations project uses the Realtek RTL2838 hardware to receive signals in the range emitted by radio stations to track them in a nearby radius. I plotted and identified about 20 stations surrounding the San Francisco East Bay region, then made a waterfall plot displaying the corresponding frequencies.
The hack_rf notebook teaches using the HackRF hardware, along with GNU Radio software, to detect and process cellphone transmissions. HackRF outputs data in I/Q binary format and has first to be converted to floats. The end result of the notebook displays the received cellband transmissions as a function of frequency.
One of the most fascinating aspects of space is the omnipresent 21cm hyperfine transition radiation emitted from dust containing neutral hydrogen. Connecting my HackRF to a rooftop telescope at the university and using the gqrx visualization software, I displayed the 21cm line.
This is one of my undergraduate lab reports. The work involved celestial coordinate transformation, the physics of interferometry, processing real-time data from the Sun, Moon, and Orion Nebula. Least-squares regression was applied to the lunar data to visualize the power of the data as a function of radians. The processed data is used to produce results on various characteristics of the celestial objects, such as the size of the object projected onto the sky, which would be useful for image reconstruction.