Coupler Directivity Calculator is used to calculate the minimum and maximum values of Reflection Coefficient, VSWR, Return Loss and Mismatch Loss. The Directivity Error Calculator shows the accuracy of a reflection measurement of unknown impedance. It bases its readings on the directivity of the coupler used for the measurement. It is also a convenient way to convert a reflection coefficient to an equivalent standing wave ratio (SWR), return loss, or mismatch loss. LIKE and Share us: Go