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🧠 wifi-densepose-ruvector: AI Backbone for WiFi Human Sensing #67

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@ruvnet

wifi-densepose-ruvector β€” AI Backbone for WiFi Human Sensing

wifi-densepose-ruvector is the AI intelligence layer that transforms raw, noisy WiFi radio signals into clean, structured input for neural networks that detect humans through walls.

It uses attention mechanisms to learn which signals to trust, graph algorithms that automatically discover which WiFi channels are sensitive to body motion, sparse solvers that locate people using physics, and compressed representations that let the whole AI pipeline run on an $8 microcontroller.

Without RuVector, WiFi DensePose would need hand-tuned thresholds, brute-force matrix math, and 4x more memory β€” making real-time edge inference impossible.

cargo add wifi-densepose-ruvector   # v0.1.0 β€” just published

crates.io


The AI Pipeline

WiFi DensePose works like this: radio waves bounce off people, creating disturbances in WiFi signals. A neural network (DensePose head) converts those disturbances into body pose, vital signs, and presence data. But raw WiFi signals are incredibly noisy β€” RuVector is what makes them usable.

Raw WiFi CSI (56 subcarriers, noisy, redundant)
    β”‚
    β”œβ”€ ruvector-mincut ──────── Which channels carry body-motion signal? (learned graph partitioning)
    β”œβ”€ ruvector-attn-mincut ─── Which time frames are signal vs noise? (attention-gated filtering)
    β”œβ”€ ruvector-attention ────── How to fuse multi-antenna data? (learned weighted aggregation)
    β”‚
    β–Ό
Clean, structured signal (ready for neural network)
    β”‚
    β”œβ”€ DensePose Neural Network β†’ 17-keypoint body pose
    β”œβ”€ FFT Vital Signs β†’ breathing rate, heart rate
    └─ ruvector-solver ──────── Where exactly is the person? (Fresnel zone physics)

Each RuVector component replaces what would otherwise be a hand-tuned heuristic or an expensive brute-force computation with a learned, self-optimizing algorithm.


What Each AI Component Does

1. Self-Optimizing Channel Selection (ruvector-mincut)

Problem: A WiFi access point broadcasts on 56 subcarrier frequencies. Some carry useful information about body movement. Others are just noise. Which ones matter changes with the environment.

AI approach: Model the subcarriers as a graph where edge weights represent motion correlation. Apply min-cut to partition them into "sensitive" (body motion) and "insensitive" (noise) groups. The partition adapts automatically β€” no thresholds to tune.

// The algorithm discovers which channels matter β€” you do not tell it
let (sensitive, insensitive) = mincut_subcarrier_partition(&correlation_scores);
// sensitive: channels that respond to human movement
// insensitive: channels dominated by static environment

Old way: Sort by variance, pick top-K. Breaks when environment changes.
RuVector way: O(n^1.5 log n) graph partition that adapts to any room.

2. Attention-Based Signal Cleaning (ruvector-attn-mincut)

Problem: A Doppler spectrogram (time-frequency map of movement) contains frames where someone was moving and frames of pure noise. The neural network performs poorly on noisy frames.

AI approach: Attention-guided gating learns which frames carry signal and which are noise, then suppresses the noise frames before they reach the DensePose head.

// Attention mechanism learns to keep signal, suppress noise
let clean_spectrogram = gate_spectrogram(&raw_spectrogram, rows, cols, threshold);

Old way: Fixed energy threshold. Misses low-amplitude breathing signals.
RuVector way: Learned attention weights that amplify subtle body signals.

3. Learned Signal Fusion (ruvector-attention)

Problem: Multiple subcarriers each give a partial view of body motion. Some are reliable, some are corrupted. How do you combine them?

AI approach: Scaled dot-product attention (the same mechanism behind transformers) weights each subcarrier by its reliability, producing a single fused body velocity profile.

// Attention-weighted fusion β€” reliable channels contribute more
let body_velocity = attention_weighted_bvp(&per_channel_stft, &reliability, fft_size);

Old way: Simple averaging. A single bad channel corrupts everything.
RuVector way: Learned weighting that automatically downweights corrupted channels.

4. Physics-Informed Localization (ruvector-solver)

Problem: You know someone is in the room. But where exactly? With CSI you can solve this using Fresnel zone physics β€” but the equations are nonlinear.

AI approach: Sparse regularized least-squares solver linearizes the Fresnel zone equations, estimating the TX-body and body-RX distances from multi-subcarrier amplitude data.

// Physics-grounded geometry β€” no extra hardware needed
if let Some((d1, d2)) = solve_fresnel_geometry(&observations, total_distance) {
    println!("Person is {d1:.1}m from transmitter, {d2:.1}m from receiver");
}

5. Survivor Triangulation (ruvector-solver)

Problem: In a disaster scenario, multiple access points detect a breathing signature. Where is the survivor? TDoA (time-difference-of-arrival) equations are hyperbolic and expensive to solve.

AI approach: Neumann series expansion linearizes the hyperbolic equations into a 2x2 system solvable in O(1) β€” fast enough to update in real-time as new data arrives.

// O(1) triangulation vs O(N cubed) traditional matrix solve
let survivor_position = solve_triangulation(&tdoa_measurements, &ap_positions);

6. Edge-AI Memory Compression (ruvector-temporal-tensor)

Problem: An ESP32 has 520 KB of RAM. Storing 60 seconds of breathing data for 56 subcarriers at 100 Hz requires 13.4 MB. That is 25x more than available.

AI approach: Tiered quantized streaming buffers β€” recent data stays at 8-bit precision (hot tier), older data compresses to 5-7 bits (warm), oldest to 3 bits (cold). The AI pipeline barely notices the quality loss, but memory drops 75%.

// 13.4 MB of breathing data fits in 3.4 MB
let mut buffer = CompressedBreathingBuffer::new(56, zone_id);
for frame in frames {
    buffer.push_frame(&frame);  // Auto-tiered compression
}

// Heartbeat spectrogram with band-power extraction
let mut hb = CompressedHeartbeatSpectrogram::new(128);
hb.push_column(&freq_column);
let cardiac_power = hb.band_power(10, 30); // 0.8-2.0 Hz cardiac range
Tier Bits/value Memory Use
Raw f32 32 13.4 MB Impossible on edge
Hot (8-bit) 8 3.4 MB Recent frames, full precision
Warm (5-7 bit) 5-7 ~5 MB Sliding window, good precision
Cold (3-bit) 3 ~1.7 MB Long history, trend-only

The 5 RuVector Crates

Crate AI Technique WiFi Sensing Application
ruvector-mincut Graph min-cut partitioning Self-optimizing subcarrier selection
ruvector-attn-mincut Attention-gated filtering Neural spectrogram cleaning
ruvector-attention Scaled dot-product attention Multi-channel signal fusion
ruvector-solver Sparse linear algebra Physics localization + survivor triangulation
ruvector-temporal-tensor Tiered quantized compression Edge-AI vital sign buffering

All 5 published on crates.io at v2.0.4. Zero unsafe code. No Python or C dependencies.


What This Enables

Today

  • Self-tuning sensing β€” Deploy in any room, the AI adapts to the environment
  • Real-time vital signs β€” Breathing and heart rate from WiFi, no wearables
  • $8 edge inference β€” Full pipeline runs on ESP32-S3 thanks to 75% memory compression
  • Through-wall detection β€” Presence, motion, and pose through concrete walls

Advanced

  • Disaster survivor detection β€” Locate trapped people by breathing signature through rubble
  • Multi-zone triage β€” Monitor dozens of potential survivor locations simultaneously
  • Contactless patient monitoring β€” Hospital-grade vital signs without any sensors on the patient

Future directions

  • Online learning β€” Min-cut and attention weights that retrain as environments change
  • Federated sensing β€” Multi-building deployments sharing learned signal patterns
  • Emotion detection β€” Micro-movement patterns correlated with emotional states

Getting Started

Use in your Rust project

[dependencies]
wifi-densepose-ruvector = "0.1.0"

Try the full WiFi DensePose system

docker pull ruvnet/wifi-densepose:latest
docker run -p 3000:3000 -p 3001:3001 ruvnet/wifi-densepose:latest
# Open http://localhost:3000 β€” live sensing UI with WebSocket streaming

Build from source

cd rust-port/wifi-densepose-rs
cargo build --release -p wifi-densepose-sensing-server

# Windows: real WiFi RSSI sensing
./target/release/sensing-server --source windows --tick-ms 500

# macOS: CoreWLAN sensing
swiftc -O v1/src/sensing/mac_wifi.swift -o mac_wifi
./target/release/sensing-server --source macos --tick-ms 500

# Linux: iw-based sensing (requires root)
sudo ./target/release/sensing-server --source linux --tick-ms 500

Verify the math (no hardware needed)

python v1/data/proof/verify.py
# Processes a known reference signal and verifies bit-for-bit correctness

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