What this thing is

This site is the public face of a PhD research project at FIIT STU Bratislava about a simple question with an annoying answer: how many people are in this room?

Cameras can tell you, but nobody wants cameras everywhere. Wearables can tell you, but only if everyone agrees to wear one (they won't). So we listen to something that's already there: the WiFi. People are mostly water, water absorbs and scatters radio waves, and the Channel State Information (CSI) that WiFi hardware reports for free turns out to wobble in proportion to the crowd. The catch — and the thesis — is that this wobble drifts: move a chair, and yesterday's model is confidently wrong. We counter that with periodic BLE calibration campaigns, crowd-flow simulation, and a lot of stubbornness.

Everything here is generated from the actual research vault — the same notes, experiments and reading logs the work is done in. Nothing is written for the website; the website just tells you what happened. That means:

  • Experiments — simulations, measurement campaigns and their results: figures, trajectory replays, synthesis reports. Including the ones that failed, because those are usually the informative ones.
  • The building — the floors we've digitised and the devices deployed on them.
  • Research map — the concepts this field is made of, and how they connect.
  • Read — long-form explainers distilled from the papers we read.

Who's behind it

Jakub Dubec — PhD student at the Faculty of Informatics and Information Technologies, Slovak University of Technology in Bratislava. Software engineer by trade, researcher by escalation: it started with "how hard can counting people be?" and is now a thesis.

By day I build the pipelines that read papers, run simulations and argue with me about my own conclusions. By night the pipelines run unsupervised and leave reports for me to find in the morning, like a very diligent cat leaving dead birds.

Things I will happily talk about for too long: channel state information, indoor positioning, crowd dynamics, why your office WiFi knows you're in a meeting before your calendar does, and self-hosted research infrastructure.

If any of this is relevant to your interests — student, researcher, or person who just really wants to know how many people are in a room — write me.

Last updated 2026-06-05 · Reach out: jakub.dubec@stuba.sk