The useful model: Loss resistance is the equivalent feed-point resistance representing power dissipated as heat in conductors, ground, cores, loading coils, connections, and nearby materials.
What controls the result
Radiation resistance and loss resistance can add to a convenient feed resistance, so a 50-ohm match may include mostly useful radiation—or mostly heat.
The misleading shortcut
SWR and resistance measured at the radio cannot separate these terms, especially after feed-line loss transforms the load.
Make the better decision
Use controlled models or comparative field measurements, inspect component Q and temperature, minimize ground and common-mode loss, and measure at the antenna reference plane where possible.
Evidence boundary
Propagation and antenna metrics are meaningful only with their frequency, path, geometry, reference plane, loss assumptions, and measurement method. Use current observations and the exact installed system.
