CBO–TGRA · Stage 0 · USC–NGA CRADA
Physics-informed buffers and the MTEBB envelope
Stage 0 defines the analytical universe 𝒰 = 𝔅 ∪ 𝔓 ∪ 𝔖. The statutory buffer 𝔅 is the government's fixed circle; the shadow buffer 𝔖 absorbs positional uncertainty; the physics pathway 𝔓 asks what a parcel could physically enable against the facility through four exploitation modalities. The MTEBB envelope is their per-azimuth maximum. Everything on this page is computed live from a synthetic terrain scene.
How to read the scene
The cardinal point is the protected facility. The dashed circle is 𝔅, the dotted circle is 𝔖, and each coloured hull is one modality's reach. The thick cardinal line is the MTEBB envelope, and the faint fill behind everything is 𝒰. Parcels are coloured by the pathway that admitted them; excluded parcels stay hollow. The surface layer paints the underlying field for one modality: visibility probability, link margin, travel time, or UAS endurance margin.
Toggling a pathway removes it from 𝒰 and from the envelope, so the parcel counts and the universe area respond immediately. The azimuth chart shows the same envelopes unrolled by bearing, which makes the maximum rule visible as the upper edge of the coloured lines.
Model notes
- VIS viewshed
- Radial line of sight from the facility target height to an observer on each parcel, repeated over Monte Carlo draws of target height, observer height, and correlated terrain error. Admission uses the probability of an unobstructed sight line, so false deterministic precision never enters the screen.
- RF propagation
- Free-space path loss plus single knife-edge diffraction from the dominant terrain obstruction of the first Fresnel zone, plus a clutter term per kilometre. A link closes where the loss stays inside the budget.
- MOB network reach
- A Dijkstra isochrone over the terrain grid with road speed on the network and a slope-penalised off-road speed elsewhere. The hull follows corridors instead of terrain shadow.
- UAS feasibility
- Round-trip range from usable endurance, cruise airspeed, and the wind vector resolved into along-track and crosswind components, plus the observation standoff. Piloted missions add a command-link range and terrain line of sight from the operator to the aircraft at altitude; autonomous missions remove it. Geofence compliance is an assumption the screen deliberately declines.