Introducing the Moorland Discovery Project

The vastness of British moorland carries lots of secrets. The debris of crashed planes, hidden caves, neolithic burial mounds, walls marking the outlines of long-forgotten farms, slight bumps marking the path of Roman roads, ruins of buildings centuries old, and many, many lost sheep.

One day while hiking off path on the open moorland, I found a solar-powered box of something. The box is easy to miss. It’s a few hundred meters from the nearest path and hidden from the path behind a few sloughs of rolling peat. I would guess that only a few dozen people have ever ventured to the right place to see it.

The origin of the box isn’t particularly mysterious. While it isn’t registered with Ofcom, research suggests the box is almost certainly a monitoring station used by an organization tasked with restoring the surrounding moorland. But the box has raised a question I cannot get out of my head:

What else is out there?

This question is the basis of the Moorland Discovery Project. This will be my first real experience with a lot of concepts related to embedded systems and electronics, so goals of the project are three-fold:

1. Locate and identify electronics on the moorland

2. Serve as a personal introductory project to the world of microcontrollers and security research

3. Do some killer fell walking in the process

The Game Plan

The strategy at the start of the project is to build a suite of sensors I can stick in my backpack that can be used to identify possible sites of electronics.

I will assume for now that the box transmits some sort of radio broadcast, at least periodically. This seems like a safe assumption, since the box is just over an hour’s brisk walk from nearest road and closer to a 90 minute walk from the nearest public car park. Of course, last time I was up there I didn’t check for antennas…

The hope is that if I hike across the moors carrying a device capable of GPS tracking and RF spectrum analysis (or some other way of measuring RF signal strength), I can use the data to identify likely locations for source of radio transmissions. Strong signals will indicate the location of a possible monitoring station, which I can then check out on foot.

So the device will need to be designed to stuff into a backpack and be composed of:

1. An RF spectrum analyzer

2. A GPS tracker

3. A storage device

4. A battery

5. (optional) A display

I know I could shell out for a fancy spectrum analyzer, but because this is meant to be a learning experience, I want to keep the design as bootleg as possible. The more I build from the ground-up, the better. So I am also avoiding using a USB SDR dongle with a raspberryPi, instead sticking to ESP32, Arduino, and cheap parts from eBay. At least for now. Ask me again in a few months.

Challenges

A lot of this ground is new to me and will require a lot of research and testing. Here are a few challenges in no particular order.

1. Developing a scanner with the right frequencies. I currently know very little about how the RF spectrum is populated. This will need to be learned and the right devices for checking the right frequencies will have to be acquired.

2. Adequately building the system. The scanner will need to be stuffed in a backpack. It will be jostled and may share that backpack with clothes, food, and water bottles. The inside of the backpack will get a bit damp if the hike is inside clouds or in the rain.

3. Antennas? Will I need beefy antennas? Again, this is new ground for me. Since I will occasionally pass other humans, the more I can hide any antennas, the better. I don’t want to be the crazy guy on the moors. Or at least any more than I already am.

4. Speaking of other humans, there will be lots of other RF signals on the hills. Depending on the frequencies I search, I may pick up other hiker’s cell phones, and if I go out on weekdays there will likely be walkie-talkie chatter. Hopefully I can sort this out at the same time as the challenge:

5. Math. What will I do when I get data? Math is definitely not my strong suit, but I may have to change that.

First step

The project is going to proceed in two directions to start.

First, I need to check that the mysterious box actually transmits frequencies I can measure. I need to build some sort of frequency scanner and lug it up to the box.

Second, I need to develop a way to combine GPS coordinates with frequency data. I plan to store this in a csv or tsv, but this requires some code and shopping on eBay.