Apparatus for and method of measuring clock skew
AssigneeAdvantest Corporation
InventorsTakahiro Yamaguchi, Masahiro Ishida, Mani Soma
Life of this patent
Estimating the term…
Abstract
Timing jitter sequences Δφj[n] and Δφk[n] of respective clock signals under measurement xj(t) and xk(t) are estimated, and a timing difference sequence between those timing jitter sequences is calculated. In addition, initial phase angles φ0j and φ0k of linear instantaneous phases of the xj(t) and xk(t) are estimated, respectively. A sum of a difference between those initial angles and the timing difference sequence is calculated to obtain a clock skew sequence between the xj(t) and xk(t).
Claims25
An apparatus for measuring a clock skew between a plurality of clock signals under measurement comprising:
- a timing jitter estimator to which the plurality of clock signals under measurement are inputted for estimating their respective timing jitter sequences;
- and
- a clock skew estimator to which the plurality of timing jitter sequences are inputted for calculating a timing difference sequence between those timing jitter sequences to output a clock skew sequence.
A method of measuring a clock skew between a plurality of clock signals under measurement comprising:
- a step of estimating timing jitter sequences of the respective clock signals under measurement;
- and
- a step of calculating a timing difference sequence between the plurality of timing jitter sequences to estimate a clock skew sequence.
Dependencies are inferred from the claim text.