Cal-ing the Coax with SOLs, and Other Awesome Jargon

Welcome to my Senior Research Project blog! My name is Luke Wohlford, and I throughout the course of my project I will be working with Dr. Melde of the University of Arizona, some of her graduate students, and an Engineering Senior Design team to learn about the new innovations in tracking-collar technology for small mammals. For three years Engineering Senior Design teams at the University of Arizona have been working on tracking collars for the Golden Lion Tamarin, but much of my own project will be concerned with how the new technology can be applied towards tracking collars for the Monterrey Bay Otters.

I finally got to meet Dr. Melde and her team of graduate students on Monday, and I have a lot of reading to do on previous projects. Fortunately I already have the chance to get my hands dirty this week, since I have been asked to build several PIFAs. PIFA stands for Planar-Inverted-F Antenna, the F resulting from the F-shape. Today, one of the graduate students taught some Computer Engineering seniors and me how to calibrate a network analyzer using a short circuit, and open circuit, and a 50 Ohm load (SOL for short) so that we can test to make sure that our antennas resonate at the correct frequencies. It was like using a TI-83 on steroids, which, needless to say, was awesome.

The magnificent network analyzer, in all of its calibrated glory

After the demonstration, I got to use a caliper, one of the coolest things ever, to measure the already-built PIFAs so that I could get the dimensions for my new antennas. I got a little zealous and ended up measuring three different old PIFAs with different frequencies so that I could figure out the exact proportions of the different planes, the coaxial copper wire, and the distance between the planes and how they were all proportional to the wavelength or frequency. I'm a numbers guy, so it was a ton more fun than I'm probably making it sound, and now I'm ready to learn how to solder and build these PIFAs!

A PIFA and some of my calculations

The caliper (bottom), which electronically measures lengths

One more thing. There's a LOT of jargon that the electrical engineers and microwave engineers are throwing around. I mean, I definitely expected that from working with engineers, but it's pretty fun to talk in jargon and try to figure out what my parents would think if they heard what I'm saying. Everything that can be made an acronym already has one, and if an item is only two words long, most of the time it's cut down to two syllables. Need a coaxial cable? Just ask for a coax. Need a purple pen? Just ask for a pup (kidding). Also, having a larger bandwidth apparently isn't always a bad thing, because it can also mean that you have more free time. Clever, no? Overall, I'm really enjoying my project so far, and I'm really looking forward to the rest of what I will be doing over these next few months.