radioplanbr — RF coverage planning in the browser

radioplanbr is a browser tool for planning amateur-radio coverage: where a signal reaches, given terrain, antenna, and band. It runs entirely client-side, with no server of its own.

Propagation as models. Coverage is estimated with established path-loss models — Okumura-Hata, COST-231, ECC-33, Friis, Ericsson — selected by band and environment, with terrain and line-of-sight taken into account rather than assuming free space.

HF is a different problem. Above VHF, coverage is mostly geometry; on HF it depends on the ionosphere, which changes by the hour. radioplanbr adds an HF skywave model fed by real-time ionospheric data from NOAA, so a prediction reflects current conditions instead of a static assumption.

The map carries the detail. On top of the coverage estimate, the map shows the antenna radiation diagram rotated by azimuth, polarization, Maidenhead grid locators, and the CQ/ITU radio zones for the transmit site. Repeaters can be registered and persisted locally, imported and exported as JSON.

radioplanbr is on GitHub.