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Sensor-less human detection? It’s not magic—it’s 5GHz physics. 👤🚫

Because the XIAO ESP32-C5 operates on the 5GHz band, its shorter wavelengths are hypersensitive to human movement. So you can monitor a room's occupancy using NOTHING but the Wi-Fi signal.
High precision, zero privacy concerns. 🤯

See how to achieve it: https://tutoduino.fr/en/wifi-presence-detection/

https://blog.adafruit.com/2026/02/14/from-pdf-to-lbr-using-deep-think-to-write-custom-cad-parts/

Just a moment...

High-speed sensing often fails not because the sensor is slow, but because the amplifier can’t keep up. When signals live in the GHz range, bandwidth, noise, and slew rate decide whether you see real data or just distortion.
OPA855 is built for that extreme edge. With 8 GHz bandwidth and an ultra-high 2750 V/µs slew rate, it can respond to tiny, fast current pulses without rounding or delay. That’s why it fits perfectly as a high-speed transimpedance amplifier (TIA) in optical systems.
In this setup, a pulsed laser hits an object and the reflected light is captured by photodiodes. The current from those diodes is extremely small and very fast. OPA855 converts that current into a clean voltage while feedback components (RF and CF) control stability and noise. The fast comparator then creates precise timing edges, allowing the time-to-digital converter to measure distance accurately.
Low voltage noise (0.98 nV/√Hz) matters here—it preserves weak reflections that define range resolution. This is exactly why OPA855 shows up in LiDAR, drone vision, and 3D scanning, where every nanosecond counts.
If you had to capture sub-nanosecond optical pulses, would your amplifier be fast enough—or would it blur the truth?

BREAKING NEWS
The Royal Swedish Academy of Sciences has decided to award the 2025 in Physics to John Clarke, Michel H. Devoret and John M. Martinis “for the discovery of macroscopic quantum mechanical tunnelling and energy quantisation in an electric circuit.”

This year’s physics laureates’ experiments on a chip revealed quantum physics in action.

A major question in physics is the maximum size of a system that can demonstrate quantum mechanical effects. The 2025 physics laureates conducted experiments with an electrical circuit in which they demonstrated both quantum mechanical tunnelling and quantised energy levels in a system big enough to be held in the hand.

Quantum mechanics allows a particle to move straight through a barrier, using a process called tunnelling. As soon as large numbers of particles are involved, quantum mechanical effects usually become insignificant. The laureates’ experiments demonstrated that quantum mechanical properties can be made concrete on a macroscopic scale.

In 1984 and 1985, John Clarke, Michel H. Devoret and John M. Martinis conducted a series of experiments with an electronic circuit built of superconductors, components that can conduct a current with no electrical resistance. In the circuit, the superconducting components were separated by a thin layer of non-conductive material, a setup known as a Josephson junction. By refining and measuring all the various properties of their circuit, they were able to control and explore the phenomena that arose when they passed a current through it. Together, the charged particles moving through the superconductor comprised a system that behaved as if they were a single particle that filled the entire circuit.

This macroscopic particle-like system is initially in a state in which current flows without any voltage. The system is trapped in this state, as if behind a barrier that it cannot cross. In the experiment the system shows its quantum character by managing to escape the zero-voltage state through tunnelling. The system’s changed state is detected through the appearance of a voltage.

The laureates could also demonstrate that the system behaves in the manner predicted by quantum mechanics – it is quantised, meaning that it only absorbs or emits specific amounts of energy.

The transistors in computer microchips are one example of the established quantum technology that surrounds us. This year’s Nobel Prize in Physics has provided opportunities for developing the next generation of quantum technology, including quantum cryptography, quantum computers, and quantum sensors.

Learn more
Press release: https://bit.ly/42jAlZg
Popular information: https://bit.ly/4gKFvTX
Advanced information: https://bit.ly/48CSBjZ

Trixie — the new version of Raspberry Pi OS - Raspberry Pi New Raspberry Pi OS Trixie has an updated desktop theme, a new Control Centre application, easier customisation possibilities, and more.