# Multi-GNSS availability from orbital geometry: GPS + Galileo combined.
#
# The same geometry-derived availability as orbit-gnss-challenged.toml, but the
# user now sees two constellations at once. Combining GPS and Galileo roughly
# doubles the visible-satellite count, lifting availability and tightening the
# dilution of precision for the same challenging user orbit. Add further
# `[[constellations]]` blocks (GLONASS, BeiDou) to model full multi-GNSS.
# Vendor-neutral; constellation parameters are public/cited.

kind = "orbit"
seed = 7
threshold_ns = 5.0
mask_deg = 10.0
sigma_uere_m = 1.0

[time]
step_s = 60.0
duration_s = 86400.0   # one day

# User spacecraft at ~8,000 km altitude, inside the GNSS shell.
[user]
altitude_km = 8000.0
inclination_deg = 0.0

# Primary constellation: GPS-like Walker-delta (24 sats, 6 planes, 55 deg,
# ~20,180 km; IS-GPS-200 / USCG NAVCEN).
[constellation]
altitude_km = 20180.0
inclination_deg = 55.0
planes = 6
sats_per_plane = 4
phasing_f = 1.0

# Additional constellation: Galileo-like Walker (24 sats, 3 planes, 56 deg,
# ~23,222 km; European GNSS Service Centre / Galileo OS SIS ICD).
[[constellations]]
altitude_km = 23222.0
inclination_deg = 56.0
planes = 3
sats_per_plane = 8
phasing_f = 1.0

[clock_quantum]
id = "optical-sr-lattice"
provenance = "Strontium optical lattice clock, space-oriented goal sigma_y(1s)=1e-15 (arXiv:1503.08457); not flown."
y0 = 1.0e-15
q_wf = 1.0e-30
q_rw = 1.0e-40

[clock_classical]
id = "csac-sa45s"
provenance = "Microchip SA.45s / SA65 chip-scale atomic clock, sigma_y(1s)=3.0e-10 (datasheet); deployed commercial part."
y0 = 1.0e-11
q_wf = 9.0e-20
q_rw = 1.0e-28
