I spent a day in the lab building my antenna out of coaxial cable and SMA connectors - Caitlin

The STEM placement students are sending us weekly blogs all about their experience in the world of work! 

Work experience is great and it provides students with many benefits whilst gaining skills and helping choose the right future career path for pupils. Having work experience on a Curriculum Vitae will make a person stand out to employers as they will notice they have motivation and a real passion for work. It will also help to boost a students confidence in themselves!

See how Caitlin got on at her Extended Work Placement! 

Week one - 

"It’s the end of my first week at Surrey satellites, and I’m already having an amazing time. The week began with me being rather lost at Guildford train station, before spotting the minibus which takes me directly to Tycho house. The receptionist was lovely and guided me through the signing in process which I would have to complete every morning. 

Once I had received my work experience card, Andy was called down to meet me. He was very welcoming and gave me a tour of both the office (Tycho) and lab (Kepler) buildings. I was told what codes I needed to get into each building, where to go and who to ask for technical help, and most importantly, where to go for lunch! From there, I was taken to IT to receive a laptop for me to work on at my time at Surrey Satellites. I was given a laptop rather than a desktop as many of my experiments involved moving buildings or staying outside for prolonged periods of time. The rest of the week mainly consisted of research into what ADS-B actually was, and different computer programs to find and record ADS-B signals.

 I also got a chance to learn how to solder professionally which I’d never done before! I can’t wait for next week!"

Week two - 

"My second week at SSTL went really well, and I’m amazed by how much I’ve learnt. I was given an ‘RTL-SDR dongle’ by a colleague (a device which is tuned to 1090Mhz, ADS-B frequency) and I’ve managed to get it working, with some help from IT! I’ve been using programs such as SDR# and DUMP1090 to convert the received signals into aircraft data, and RTL1090 to plot the data into a live map showing where aircraft are in the nearby area.

 My next goal is to increase the range of the antenna, either by building a new antenna myself, or perhaps by using a LNA to boost the signal. I’ve also been calculating the range the antenna should receive by using some tricky calculations involving antenna gain, using measurements I hadn’t heard of before I came here! I found that my antenna should receive a lot more signals than it currently is, but this lack of signal may be down to the large buildings and trees nearby that are blocking the signal. I’m looking forward to building things next week!"

Week three - 

"It’s the end of another week, and there has been a small amount of improvement! After a lot of research, I discovered that an antenna design worth trying would be a ‘coaxial collinear antenna’. A study online described the calculations for the proportions of the antenna in detail which was just what I needed! Next, I headed down to the lab and put on all of the necessary gear. It’s taken some time to get used to, but now putting on all of the electrostatic protection and clean room clothes feels like second nature. 

I spent a day in the lab building my antenna out of coaxial cable and SMA connectors, before taking it out to test. To my surprise, it worked quite well, though somewhere my measurements weren’t perfect as the antenna was slightly out of tune. It worked wonderfully at 900-1000Mhz, but not at that magic 1090Mhz that I was looking for! We still tested it in the ‘R2D2 building’ – named as such because of its shape – and my signal strength and range has increased slightly. Next week I hope to make another antenna with what I’ve learned!"

Week four - 

"I can’t believe my time at SSTL has come to an end already, it feels as if I only started yesterday! In my final week, I managed to significantly improve my antenna design, so much so that I’m now receiving signals from as far as Scotland! This time, I decided to create a helical antenna with a copper baseplate. This antenna would be much more predictable as the calculations were simpler and it could easily be adjusted. The antenna expert very kindly helped me with my design by showing me how to 3D print with solidworks. The 3D print would have a groove carved into the outside of a cylinder, to make the angle of the wire more accurate than I could by hand. 

The print took over 25 hours, but in the end made my antenna so much more solid and stable. When we tested the antenna on an RF analyser in an anechoic chamber, we found that the antenna had a huge gain at 1090Mhz, which was exactly what I wanted! As expected, the antenna worked really well, so well in fact that the computer program couldn’t handle the amount of data that we were discovering!

There are so many more things I’d like to try but unfortunately my time here has come to an end. I said my goodbyes and gave out presents and cards on my last day and yet I didn’t feel like it was enough after everything that everyone had done for me. Hopefully I’ll get to work with some of these people again!"

                                                                                                                                  - Caitlin