RF Topological Sensing — Research Index
SOTA Research Compendium
Generated: 2026-03-08
Total Documents: 12
Total Lines: 14,322
Branch: claude/rf-mincut-sensing-uHnQX
Core Concept
RF Topological Sensing treats a room as a dynamic signal graph where ESP32 nodes
are vertices and TX-RX links are edges weighted by CSI coherence. Instead of
estimating position, minimum cut detects where the RF field topology changes —
revealing physical boundaries corresponding to objects, people, and environmental
shifts. This creates a "radio nervous system" that is structurally aware of space.
Document Index
Foundations (Documents 1-2)
| # |
Document |
Lines |
Key Topics |
| 01 |
RF Graph Theory & Mincut Foundations |
1,112 |
Max-flow/min-cut theorem, Stoer-Wagner/Karger algorithms, Fiedler vector, Cheeger inequality, spectral graph theory, comparison to classical RF sensing |
| 02 |
CSI Edge Weight Computation |
1,059 |
CSI feature extraction, coherence metrics, MUSIC/ESPRIT multipath decomposition, Kalman filtering of edges, noise robustness, normalization |
Machine Learning (Documents 3-4)
| # |
Document |
Lines |
Key Topics |
| 03 |
Attention Mechanisms for RF Sensing |
1,110 |
GAT for RF graphs, self-attention for CSI, cross-attention fusion, differentiable mincut, antenna-level attention, efficient attention variants |
| 04 |
Transformer Architectures for Graph Sensing |
896 |
Graphormer/SAN/GPS, temporal graph transformers, ViT for spectrograms, transformer-based mincut prediction, foundation models for RF, edge deployment |
Algorithms (Document 5)
| # |
Document |
Lines |
Key Topics |
| 05 |
Sublinear Mincut Algorithms |
1,170 |
Sublinear approximation, dynamic mincut, streaming algorithms, Benczúr-Karger sparsification, local partitioning, Rust implementation |
Hardware & Systems (Documents 6, 10)
| # |
Document |
Lines |
Key Topics |
| 06 |
ESP32 Mesh Hardware Constraints |
1,122 |
ESP32 CSI capabilities, 16-node topology, TDM synchronization, computational budget, channel hopping, power analysis, firmware architecture |
| 10 |
System Architecture & Prototype Design |
1,625 |
End-to-end pipeline, crate integration, DDD module design, 100ms latency budget, 3-phase prototype, benchmark design, ADR-044, Rust traits |
Learning & Temporal (Documents 7-8)
| # |
Document |
Lines |
Key Topics |
| 07 |
Contrastive Learning for RF Coherence |
1,226 |
SimCLR/MoCo for CSI, AETHER-Topo extension, delta-driven updates, self-supervised pre-training, triplet edge classification, MERIDIAN transfer |
| 08 |
Temporal Graph Evolution & RuVector |
1,528 |
TGN/TGAT/DyRep, RuVector graph memory, cut trajectory tracking, event detection, compressed storage, cross-room transitions, drift detection |
Analysis (Document 9)
| # |
Document |
Lines |
Key Topics |
| 09 |
Resolution & Spatial Granularity |
1,383 |
Fresnel zone analysis, node density vs resolution, Cramér-Rao bounds, graph cut resolution theory, multi-frequency enhancement, scaling laws |
Quantum Sensing (Documents 11-12)
| # |
Document |
Lines |
Key Topics |
| 11 |
Quantum-Level Sensors |
934 |
NV centers, Rydberg atoms, SQUIDs, quantum illumination, quantum graph algorithms, hybrid architecture, quantum ML, NISQ applications |
| 12 |
Quantum Biomedical Sensing |
1,157 |
Biomagnetic mapping, neural field imaging, circulation sensing, coherence diagnostics, non-contact vitals, ambient health monitoring, BCI |
Key Findings
Resolution
- 16 ESP32 nodes at 1m spacing → 30-60 cm spatial granularity
- Dual-band (2.4 + 5 GHz) → 6 cm theoretical coherent limit
- Information-theoretic limit: 8.8 cm for dense deployment
Computational Feasibility
- Stoer-Wagner on 16-node graph: ~2,000 operations per sweep
- At 20 Hz: 0.07% of one ESP32 core
- Full pipeline CSI → mincut: < 100 ms latency budget
Quantum Enhancement
- NV diamond: 100-1000× sensitivity improvement at room temperature
- Rydberg atoms: self-calibrated, SI-traceable RF field measurement
- D-Wave quantum annealing: native QUBO solver for graph cuts
Biomedical Extension
- Non-contact cardiac monitoring at 1-3m with quantum sensors
- Coherence-based diagnostics: disease as topological change in body's EM graph
- Same graph algorithms (mincut, spectral) apply to both room sensing and medical
Proposed ADRs
- ADR-044: RF Topological Sensing (Document 10)
- ADR-045: Quantum Biomedical Sensing Extension (Document 12)
Implementation Phases
- Phase 1 (4 weeks): 4-node POC — detect person in room
- Phase 2 (8 weeks): 16-node room — track movement boundaries < 50 cm
- Phase 3 (16 weeks): Multi-room mesh — cross-room transition detection
- Phase 4 (2027-2028): Quantum-enhanced — NV diamond + ESP32 hybrid
- Phase 5 (2029+): Biomedical — coherence diagnostics, ambient health