Poseidon the Warwalker

Overview

Our phones, our routers, our smart devices emit invisible radio signals every second. We are surrounded by millions of interlaced signals everyday of our lives. How do you find a needle in the haystack when reading from millions of competing signals? How can you identify and read these invisible radio signals?

There is a process called warwalking that requires an expensive device that you carry around to intercept and interpret these signals. The software and hardware packages to do warwalking or wardriving costs well north of $60,000.

We built one for cheaper.

The Problem

We have worked with many different radio frequency reading equipment over the years including LoRa, Wi-FI, 3G, 4G, and 5G. A common problem we’ve seen in this domain is that many tools to inspect these invisible radio frequencies are expensive and inaccessible to a typical consumer.

The software and hardware packages to do warwalking, or wardriving, analysis will cost at least $60,000. That price tag won’t include classes to get trained in utilizing the proprietary software as well as software upgrades, which can cost thousands more.

Companies still pay these costs because the signal analysis can do a range of tasks such as probing different issues on a piece of hardware to assisting with the discovery of people lost in desolate areas like the woods who happened to have a smartwatch on them, or even detecting hidden transmitters in secure locations that may be siphoning proprietary industry information to competitors .

To avoid these ridiculous costs of competing hardware, and still own this industry standard equipment - we decided to create our own portable signal analysis equipment we call Poseidon.

Development

Turns out building the device from parts made it much more affordable. We built Poseidon’s signal analysis hardware platform to allow users to detect and decode signals within the 300 MHz - 3.8GHz range. Poseidon comes with 2 omnidirectional antennas as well as a directional antenna to assist with rapidly sweeping radio transmissions in order to detect and decode unknown traffic. We built the software platform using open source tools on the Raspbian OS, which allows the software suite to be configurable to The Garage’s needs as well as accessible to software upgrades. Our custom Raspbian image contains multiple known Signal Analysis software suites such as Aircrack-ng, Inspectrum, LTE-Cell-Scanner, and SDRAngel. The Poseiden also supports a variety of Software Defined Radio (SDR) front ends such as the Blade x40, LimeSDR, and RTL-SDR. The device was built using a Raspberry Pi 4B, 7 inch display, and a Blade x40 for the SDR front end. The Poseidon project is housed in a Pelican Case with custom designed 3D printed parts to meld the project together. Finally, we built the Poseidon to be modular - supporting external USB devices to be added and configured to the overall hardware package by the user.