The ratio of the amplitude of a standing wave at an anti-node (minimum) to the amplitude at an adjacent node (maximum). ( 188 ) Note 1: The standing wave ratio ( SWR ) in a uniform transmission line is given by
where is the reflection coefficient . Note 2: Reflections occur as a result of discontinuities, such as an imperfection in an otherwise uniform transmission line, or when a transmission line is terminated with other than its characteristic impedance .