Unit interval (data transmission)
The Unit Interval, abbreviated as UI, is an auxiliary unit of measurement for the evaluation of jitter in the context of digital signal processing and is used among other things in the ITU- T G.810 and digital video interfaces such as Serial Digital Interface (SDI ).
A unit interval (1 UI) corresponding to the period of transmitting one transmission symbol. By jitter occur in the actual time period to variations, which may consequently lead to transmission errors. Typical limits for jitter in the range of 0.1 to 0.3 UI UI. From 0.5 UI, the so-called horizontal opening of the eye diagram is closed and there is symbol crosstalk.