This program was attended by a group of six excellent highly motivated teachers from all over the country. The participants included:
- John Makous, NC
- Howard Chun, RI
- Alexis Emch, WV
- Daniel Bonnette, WV
- Tad Herman, NY
- John Clarke, FL
One of the aims of this program is to prepare teachers to implement Digital Signal Processing (DSP) projects with their students, exposing them to exciting STEM career opportunities. To its end, the first four weeks of the program involved the teachers attending daily lectures establishing a foundation in astronomy and DSP.
Astronomy topics covered included celestial sphere, astronomical time, solar time, Kepler's laws, H-R diagram, galaxies, and cosmology topics such as dark matter and galaxy rotation curves. The digital signal processing lecture has been modeled after an undergraduate DSP course to help the teachers establish a thorough foundation in topics from signal basics to fast Fourier transforms.
Additionally, the Teachers dedicated time to prepare lesson plans and activities to incorporate DSP in day to day class activities.
2. The Laboratory Sessions - Hands-on learning
Lectures were followed by daily laboratory sessions. This year in addition to re-hashing the 2017 lab material a lot of time was spent on mastering them. These focused on a systematic application of rather abstract DSP concepts in a tangible sense. This is made possible through software defined radio. The tool being used is GNURadio. GNURadio is free and open-source software framework to help develop software defined radio and signal processing applications. It can be used with readily-available low-cost external radio hardware. The structured labs end with the teachers developing their own software spectrometer a vital component of every radio telescope system.
The teachers additionally built a radio telescope from scratch. This involved assembling a low noise amplifier by soldering really small components and building a horn antenna. The horn design is such that it could be built using materials and tools one could purchase at a local hardware store. The teachers built horn antennas in the industrial design workshop at West Virginia University. The horn construction was expertly executed as an assembly line by the teachers. Along with the spectrometer, the LNA and the horn each teacher had a working radio telescope by the end of the four weeks in Morgantown. It should be noted that the teachers implemented a new iterative design for the horn antenna mount that they themselves designed! To ensure proper functioning of the telscopes several tests were performed at WVU. The performance of the LNAs were tested in our lab at WVU. The noise figure was testing inside the faraday cage in the RF lab.
Interstingly two teachers from the cohort are attending for the second time to further get an involved understanding of software defined radio in the context of Radio Astronomy. They worked to learn the details of the inner wokring of GNURadio to be able to design their custom programs and blocks to streamline the Radio astronomy data acquisition. They also worked to create DSP teaching tools in GNURadio.
3. Science Experiments
The horn antennas were tested in Morgantown and were taken to the Green Bank Observatory.
The next two weeks of the the program were spent at the Green Bank Observatory. The teachers went through a full suite of outreach activities planned by the the Green Bank Observatory. This included training on using the 40 Foot outreach telescope. They even tapped into the signal from the 40 foot. The signal from the 40 foot was routed through the SDR dongle and the GNU Radio spectrometer they designed at WVU.
Primarily, time was spent planning and executing observations using the horn antenna. The teachers deviced their own observing plan to map the whole sky. Moreover, we used the state of art facilities avalable on site to further test and improve the horn antenna. The myriad experiments conducted on site at Green Bank are as follows:
- Comparitive analysis of LNA performance
- Comparative analysis of Horn Response
- Optmization of horns
- Optimization of data acquisition Software
- Comparative analysis of analog data from 40 foot data and digital GNURadio backend
- Measuring horn beam pattern
- Milky Way Veloity Curve
- All sky map of Neutral Hydrogen
4. Students and Lessons
While at Green Bank, DSPiRA group of teachers worked with the West Virginia Governer's STEM Academy. This allowed the teachers utilize their research experience to develop and execute lesson plans. Digital signal processing activities targeted towards school children. This involved teaching DSP in Radio Astronomy through several involved activities over a couple of days. The teachers did this with three groups of children.
One of our teachers, Tad Herman, have documented their entire experience in detail on their blog:
5. Undergraduate Research
Our 2018 program involved two undergratuate students -- Andy Dycke from University of Toronto and Rhys Lockhard from West Virginia University. They worked with the inexpensive horn antenna system to attempt to detect radio transients such as pulsars. They worked with a hour horn aperture array and a custom data acquisition software to detect the brightest pulsars.