Wireless communication surrounds people at all times, even though it cannot be seen. Signals from Wi-Fi routers, Bluetooth devices, and mobile networks constantly travel through homes and cities unless blocked by heavy shielding. A France-based digital artist has developed a way to visually represent this invisible activity using light and low-cost computing hardware.
The creator, Théo Champion, who is also known online as Rootkid, designed an installation called Spectrum Slit. The project captures radio activity from commonly used wireless frequency ranges and converts that data into a visual display. The system focuses specifically on the 2.4 GHz and 5 GHz bands, which are widely used for Wi-Fi connections and short-range wireless communication.
The artwork consists of 64 vertical LED filaments arranged in a straight line. Each filament represents a specific portion of the wireless spectrum. As radio signals are detected, their strength and density determine how brightly each filament lights up. Low signal activity results in faint and scattered illumination, while higher levels of wireless usage produce intense and concentrated light patterns.
According to Champion, quiet network conditions create a subtle glow that reflects the constant but minimal background noise present in urban environments. As wireless traffic increases, the LEDs become brighter and more saturated, forming dense visual bands that indicate heavy digital activity.
A video shared on YouTube shows the construction process and the final output of the installation inside Champion’s Paris apartment. The footage demonstrates a noticeable increase in brightness during evening hours, when nearby residents return home and connect phones, laptops, and other devices to their networks.
Champion explained in an interview that his work is driven by a desire to draw attention to technologies people often ignore, despite their significant influence on daily life. By transforming technical systems into physical experiences, he aims to encourage viewers to reflect on the infrastructure shaping modern society and to appreciate the engineering behind it.
The installation required both time and financial investment. Champion built the system using a HackRF One software-defined radio connected to a Raspberry Pi. The radio device captures surrounding wireless signals, while the Raspberry Pi processes the data and controls the lighting behavior. The software was written in Python, but other components, including the metal enclosure and custom circuit boards, had to be professionally manufactured.
He estimates that development involved several weeks of experimentation, followed by a dedicated build phase. The total cost of materials and fabrication was approximately $1,000.
Champion has indicated that Spectrum Slit may be publicly exhibited in the future. He is also known for creating other technology-focused artworks, including interactive installations that explore data privacy, artificial intelligence, and digital systems. He has stated that producing additional units of Spectrum Slit could be possible if requested.
