gnss-navigation-knowledge-patch

# GNSS Navigation Knowledge Patch Baseline and covered range: GNSS navigation fundamentals through mid-2024, including GPS, Galileo, GLONASS, BeiDou, SBAS, RTK, and PPP; covers the included operational and specification updates through 2026-07-11. ## Reference index | Reference | Topics | | --- | --- | | [constellation-signals.md](references/constellation-signals.md) | GPS L2C/L1C, Galileo E1/E5/E6, GLONASS FDMA/CDMA, BeiDou B1/B2/B3 signal structures | | [galileo-services-and-osnma.md](references/galileo-services-and-osnma.md) | Galileo HAS, time offsets, SAR return link, OSNMA trust bootstrap, transport, status, availability, TTFF, and events | | [augmentation-corrections-and-products.md](references/augmentation-corrections-and-products.md) | SBAS, GBAS, DGNSS, WARTK, RTCM, RTK bases, RINEX 4, SSR, SPARTN, and IGS products | | [atmosphere-and-multipath.md](references/atmosphere-and-multipath.md) | Ionosphere-free PPP, second-order ionosphere, troposphere states and mappings, multipath bounds and diagnostics | | [zed-f9p-operations.md](references/zed-f9p-operations.md) | ZED-F9P variants, ports, configuration, correction inputs, moving base, integrity, timing, OSNMA, raw data, and IMX integration | | [receiver-software-and-timing.md](references/receiver-software-and-timing.md) | Linux serial/PPS timing, Android raw GNSS, antenna corrections, SUPL, logging, GNSS Analysis, and GNSS-SDR | ## Breaking boundaries and deprecations ### Pin data formats to exact revisions - RT...