Plain English Meaning

The various small mistakes that can creep into a GPS-calculated position. They come from the satellites themselves, from the atmosphere bending the signal, from signals bouncing off nearby surfaces, and from poor satellite arrangement overhead.

Full Definition

The collection of inaccuracies that can affect a Global Positioning System position solution, including satellite clock and orbit errors, ionospheric and tropospheric signal delays, receiver noise, multipath reflections (signals bouncing off surfaces before reaching the antenna), and geometric weakness when too few satellites are visible or they are poorly distributed across the sky.

Context Anchor

Seen in instrument flying, GPS navigation, , and any where is relying on GPS guidance instead of .