Architecture
Two tiers, because one node cannot do both jobs.
A sensor cheap enough to deploy in grids is not a sensor whose measurements survive a legal challenge. Trying to build one that is both is the standard way networks like this fail.
SCOUT and SENTINEL
SCOUT — occupancy
Swept tuner, power only, no demodulation. Answers is this channel occupied, how often, and how hard.
Cheap enough to deploy densely. Density is what makes occupancy statistics representative rather than anecdotal.
SENTINEL — evidence
Coherent IQ capture, GPS-disciplined timing, traceable calibration. Answers what exactly is that emitter, where is it, and does this hold up in a dispute.
Deployed sparsely. Each one also serves as a transfer standard.
SENTINEL nodes cross-calibrate the SCOUT fleet in the field. This is how meteorological and seismic networks solve the same problem, and it turns calibration from a per-node cost into a per-region one.
Design targets
Specifications under development. These are the acceptance criteria the hardware must meet before any node is deployed.
| Parameter | Target | Why it matters |
|---|---|---|
| Frequency range | 400 MHz – 7.2 GHz | Covers TVWS through the full upper 6 GHz IMT candidate band |
| Resolution | 1 MHz, with 100 kHz zoom on innovation bands | Channel-level occupancy in the bands under coordination |
| Full sweep time | ≤ 3 s | Fast enough to catch intermittent and bursty emitters |
| Noise floor | ≤ −105 dBm at 1 MHz RBW | Sensitive enough to see weak incumbents, not just strong ones |
| Dynamic range | ≥ 75 dB | Measures weak signals in the presence of strong co-sited transmitters |
| Amplitude accuracy | ± 2.5 dB after cross-calibration (Tier 1) | Occupancy grade. Evidentiary work uses Tier 2's traceable chain. |
Density is driven by requirement, not by coverage
Blanket uniform coverage is the wrong model. Three distinct requirements drive where nodes go, and they produce different patterns:
Incumbent protection
Clustered near registered earth stations and along high-density point-to-point corridors. Targeted, not gridded.
Representative statistics
Stratified sampling across geotypes — metro core, peri-urban, industrial, rural, agricultural. Each behaves differently and needs its own baseline.
Emitter geolocation
Deliberate clusters of coherent nodes with overlapping reception, sited where interference disputes are most likely.
Data handling
A node sweeping 6,800 frequency bins once a second produces about 2.3 GB per day. At fleet scale that is untransportable, so aggregation happens at the node: per-minute statistics, then change-thresholded reporting, reducing the stream by roughly two orders of magnitude without losing what the statistics describe.
What reaches the platform is retained permanently. Historical occupancy is the one thing in this business that cannot be bought, accelerated or recreated — a competitor starting later starts later, and stays that far behind.
Evidentiary handling
Measurements intended to support a dispute are held in an append-only archive with per-record hash chaining and periodic external anchoring, and every record carries the calibration state of the instrument that produced it.
The verification method is published, and the tool that checks it is open source. A chain that only the operator can verify is a chain the opposing expert will challenge on exactly that basis.