alcinnz
and 1 other
boosted
I've got a new paper out on eprint: Monitoring tamper-sensing meshes using low-cost time-domain reflectometry.
In the paper, I wrote up how you can build a ~200 ps resolution time-domain reflectometer from an STM32 and some cheap display bus redriver ICs. The circuit is sensitive enough to distinguish several identical copies of the same test specimen PCB from manufacturing tolerances!
blog post: https://jaseg.de/blog/paper-sampling-mesh-monitor/
paper preprint: https://eprint.iacr.org/2025/1962
The sampling edges as measured by the board itself. As you can see, using a cheap microcontroller and some cheap display signal redriver ICs along with commodity RF schottkies you can get pretty spicy edges on a budget.
The final setup. On the right is the measurement board, and on the left is the mesh test specimen plugged in. In a real application, you would integrate both into your target circuit.
