Undergraduate Radio Lab

This course consists of four laboratory experiments that concentrate on radio instrumentation and laboratory techniques. We will build receiving, observing, and data analysis systems for two telescopes: a single-dish 21-cm line system, and a 10.7-GHz interferometer. We will use these telescopes for astronomical observing projects including structure of the Milky Way galaxy, precise position measurement of several radio sources, and measurement of the radio brightness distributions of the sun and moon with high angular resolution. There is a heavy emphasis on digital data acquisition, software development in the Python language, and high-quality written reports.

Class Programmatics

• Class Code Repository: http://github.com/AaronParsons/ugradio
• Syllabus

Experiments

• Lab 1: Exploring Digital Sampling, Fourier Transforms, and both DSB and SSB Mixers
  • Groups TBD
• Lab 2: Astronomy with the 21cm Line; Some Microwave Electronics
  • Groups TBD
• Lab 3: Radio Interferometry at X Band
  • Groups TBD
• Lab 4: Mapping the HI Line: the Galaxy and Supershells
  • Galactic Warp
  • Superbubble
  • North Polar Spur
  • Magellanic Stream

General Skills Used Through-Out Course

• Python Installation and Basic Programming
• Unix Primer
• Unix Text Editors
• Latex
• Revision Control
• Least Squares
• Unit Testing

Topics by Date

Lab 1 (Analog Lab) Due Feb 6 5:00p

• Lab 1, Part 1 (Jan 16)
  • Necessary Topics
    • In the Mind: Introduction to the Fourier Transform
    • Nyquist Sampling
    • Convolution Theorem
    • Fast Fourier Transform
    • Office Hours, etc.
  • Breakout Sessions:
    • Astrobaki, Syllabus, Office Hours
    • Radio Astronomy: State of the Union
    • Tour of lab
      • Lab Components
    • Getting accounts / setting up environments
      • Unix Primer
      • Python Installation and Basic Programming, first pass
      • Introduction to Python and Plotting
      • Revision Control, first pass

• Lab 1, Part 2 (Jan 23)
  • Necessary Topics:
    • Heterodyne Mixers
  • Breakout Sessions:
    • Rope Demo
    • Python (numpy, pylab, scipy)
      • Python Installation and Basic Programming, second pass
    • Write-ups
      • Unix Text Editors
      • Latex
    • Transistors

• Lab 1, Part 3 (Jan 30)
  • Necessary topics:
    • Noise Temperature
  • Breakout Sessions:
    • Flipping Coins
    • Cooling the Noise on a Resistor
    • Writing Lab Reports
  • Lab 1 (Analog Lab) Due Feb 6 5:00p

Lab 2 (Digital Lab) Due Mar 3 5:00p

• Lab 2, Part 1 (Feb 11)
  • Quiz 4 on:
  • Breakout Sessions:
    • Discrete Fourier Transform
    • Convolving and Smoothing
    • Aliasing
    • Intro to Lab 2, pick groups

• Lab 2, Part 2 (Feb 18)
  • Quiz 5 on:
    • Data Representations
    • Digital Down Conversion
  • Breakout Sessions:
    • Data Representations demo
    • Mixing, Filtering, Decimation, and the FFT
    • Intro to ROACH

• Lab 2, Part 3 (Feb 25)
  • Quiz 6 on:
    • Synchronous and Asynchronous Logic
    • Processor Architectures
    • FIR Filters
  • Breakout Sessions:
    • Acting out various processors
    • Simulating an FIR filter
    • Lab feedback
  • Lab 2 (Digital Lab) Due Mar 3 5:00p

Lab 3 (Interferometer Lab) Due Apr 7 5:00p

• Lab 3, Part 1 (Mar 04)
  • Quiz 7 on:
    • Coordinates
    • Basic Interferometry
  • Breakout Sessions:
    • Exercise Ball Coordinates and Dynabee Precession
    • Interferometry with Strings
    • Tour of the Rooftop Interferometer

• Lab 3, Part 2 (Mar 11)
  • Quiz 8 on:
    • Measurement Equation
    • Telescope Field of View/Resolution
  • Breakout Sessions:
    • Controlling the Telescope
    • Tracking the Sun
    • Scheduling Observations

• Lab 3, Part 3 (Mar 18)
  • Quiz 9 on:
    • Basic Interferometry II
    • Least Squares
  • Breakout Sessions:
    • Linear Least-Squares in Python
    • Minimizing Chi-Square
    • Noise in Observations

• No Class (Mar 25)

• Lab 3, Part 4 (Apr 01)
  • Quiz 10 on:
    • Correlators
    • Units of radiation
  • Breakout Sessions:
    • Lab feedback
    • Presentations on progress
    • Photon bucket demo
  • Lab 3 (Interferometer Lab) Due Apr 7 5:00p

Lab 4 (Dish Lab) Due May 5 5:00p

• Lab 4, Part 1 (Apr 08)
  • Quiz 11 on:
    • Specific Intensity
    • Radio Sky
  • Breakout Sessions:
    • Leuschner Field trip
      • drive mechanism (how the dish moves)
      • feed (notice probes) and cables
      • IF setup (one channel for OH, one for HI)
      • show spectrum
      • demo action
      • spatial sampling with dish

• Lab 4, Part 2 (Apr 15)
  • Quiz 12 on:
    • 21cm Transition
    • Black-Body Radiation
    • Line Profile Functions
  • Breakout Sessions:
    • pointing control
    • how to take data
    • computing doppler width for a line of sight (assuming circular motion)

• Lab 4, Part 3 (Apr 22)
  • Quiz 13 on:
    • Emission Line Observing
    • Pulsars
  • Breakout Sessions:
    • show and tell
    • close-out plan
    • calibrating spectra
    • doppler correction

• Lab 4, Part 4 (Apr 29)
  • Quiz 14 on:
    • Calibrating the Intensity and Shape of Spectral Lines (Carl Heiles)
  • Breakout Sessions:
    • show and tell
    • displaying information in image form
  • Lab 4 (Dish Lab) Due May 5 5:00p

Unused but Useful?

• • Radiometer Equation
  • Quantization and Rounding
  • Reciprocity Theorem
  • Dipole Antennas
  • Impedance of Free Space
  • Radiometer Equation Applied to Telescopes
  • Radiometer Equation Applied to Interferometers
  • Fringe Stopping
  • Single Sideband Systems
  • Direction Dependent Beams
  • Self Calibration
  • Flux Calibration
  • Gridding
  • Earth Rotation Synthesis
  • Delay Imaging