Jitter measurements: from theory to practice

Some problems arising in jitter measurements on clock signals are discussed. The reported problems have been approached by proposing new measurement techniques, completely based on digital signal processing of raw data. For better clarity as well as in order to describe the procedure in more detail, simulated signals have been considered first. Then, for completeness, the procedure has been applied to actual signals acquired by a digital store oscilloscope. As far as the measurement of data stream jitter is concerned, ITU-T Recommendations suggest to make use of a data-to-clock converter. In this conformity, the proposed procedures can be extended to data jitter measurement as well. The research is still in progress and a new arrangement is actually being tested in order to avoid the use of the data-to-clock converter, possibly with an increase of the total measurement accuracy.