File:Null-Data-Packet-NDP-derived-CSI-encodes-reflections-from-6702244f.jpg

NDP-derived CSI encodes reflections from walls, objects, and the human body, enabling passive presence detection and movement tracking through ambient Wi-Fi.

AI-generated illustration for Null Data Packet, made with fal.ai (fal-ai/flux-2-pro).

Prompt: A floor-plan view of a room containing a Wi-Fi access point in one corner and a passive monitoring device in another corner, with a human figure standing in the centre. Radiating signal waves from the access point bounce off the walls, furniture, and the human body, creating distorted wavefront patterns that differ from the direct path. The monitoring device captures these reflected and attenuated wavefronts, illustrating how the human body's presence reshapes the channel and leaves a detectable signature in the received NDP training fields. Style: Detailed digital illustration blending technical schematic linework with painterly atmospheric rendering, as if a scientific textbook were reimagined by a noir graphic novelist. Colour palette of deep midnight blue, charcoal black, and slate grey as foundations, accented with electric teal, bioluminescent green, and cold amber. Lighting is dramatic and directional, suggesting surveillance or laboratory environments — pools of cold light against deep shadow, with occasional glowing circuit-trace highlights. Compositions favour tight framing with layered depth: foreground technical detail dissolving into abstracted background geometry. Detail level is high but purposeful, prioritising legible structure over decorative complexity. Mood is clinical yet ominous, precise yet unsettling. No text, lettering, captions, logos, watermarks or borders unless it is a technical drawing.