In 2015 I completed my degree in Electronic Engineering at the University of York. I took the four-year MEng course (along with an industrial "sandwich" year, for a total of 5) and completed a final-year project at the end (equivalent to a dissertation). My project was to build a wireless sensor network to detect the presence of the Speckled bush cricket by its distinctive mating call.

I designed circuits and built software for sensor nodes and a base station, where the sensor nodes could periodically report cricket detections to the base station, which would store them locally and (in theory) upload them over a small GSM modem. I also laid out and made a PCB for the sensor node and built a breadboard prototype of the base station. The sensor nodes used ultrasonic transducers to detect the cricket calls, controlled by an SI Labs ZeroGecko microcontroller and communicating with the base station over a HopeRF RFM69W RF transceiver. The base station used the same radio, along with an SD card for data storage, all controlled by the refreshingly cheap STM32F4 Discovery board.

Designing a suitable low-power input amplifier proved quite complicated, although by far the project's biggest challenge was getting the radios to communicate with each other - designing a lower-power access scheme is quite complex! There were also a few glitches found after manufacture and with power-on timing which I ran out of time to fix in the 4 months I had! Got a first (with distinction!) though 🎉