How much of a coil's field bleeds into its neighboring coil on a multi-coil mat, expressed as a percentage. When two coils sit close together, their fields don't always decay to zero before reaching each other. A peak reading at one coil can be partially inflated by the other coil's tail. Values below 20% mean the coils are well separated. Values at or above 20% indicate the field doesn't fully decay between coils. The reported peaks should be read with that overlap in mind. Coupling is calculated by comparing the lowest field value between two adjacent coils to their respective peaks. Each coil's reported value reflects the worst case across all of its neighbors.
A mat spreads many coils across a wide surface, and each coil lays down its own field footprint. How many coils there are is the coil count, how they are arranged is the coil layout, and the surface they cover together is the coverage area. When every coil peaks at about the same strength the coverage is uniform, and the field that spills from one coil into its neighbor is neighbor coupling.
