EX17 — Altitude Trade Sweep¶

Tags: sweep · altitude trade · coverage · repeatability Input: altitude-trade-sweep.yaml · Runtime tier: extended · Interface: CLI

Purpose¶

Compare coverage at three altitudes while repeating each altitude with two seeds that alter constellation phasing. The repetition shows whether the apparent altitude trend is larger than the sampled phasing variation.

Setup¶

The base RunSpec describes a 48-satellite constellation, European coverage, and a 24-hour timeline. A Cartesian sweep materializes six child cases.

astraeus sweep run astraeus-resources/examples/user/altitude-trade-sweep.yaml

RunSpec Focus¶

Only altitude and seed vary. Requested summary fields are extracted from every child bundle into the group JSON and CSV.

sweep:
  mode: cartesian
  dimensions:
  - path: constellation.design.orbit.altitude_km
    values: [450, 550, 650]
  - path: runtime.seed
    values: [11, 29]
  summary:
    fields:
    - coverage.covered_surface_fraction

Results¶

All six reference cases succeeded in 31.18 seconds. Represented-surface coverage was 27.12–28.24% at 450 km, 35.32–36.23% at 550 km, and 43.29–44.40% at 650 km. Each case retained its child RunSpec and complete run bundle.

Area-weighted coverage across altitude and two constellation phasing seeds

Artifacts To Inspect¶

Artifact	What it shows
`sweep_plan.json`	The six materialized override combinations and child RunSpecs
`sweep_summary.json` / `.csv`	Altitude, seed, status, timing, and requested coverage KPIs per case
`sweep_results.json`	Execution status, failures, and child-run locations
`cases/.../coverage/coverage_summary_by_area.parquet`	Full regional evidence behind each summary row

Interpretation¶

Coverage increases materially across the sampled altitude range, while the two phasing realizations differ by roughly one percentage point at each altitude. This supports an altitude trend for this constellation and mask, but it does not capture the latency, link-budget, radiation, or launch trades that altitude also changes.