Technique for combatting jitter in multiple phase transmission system
US4146841A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1977 |
| Grant date | Mar 27, 1979 |
| Priority date | — |
| Expiry date | Sep 28, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/22
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
To eliminate the effects of phase jitter, successively measured phase values received in an N-phase transmission system are stored and compared with a phase node reference plot to derive values representative of the respective phase nodes to which the measured phase values are closest and the degree of deviation from these "closest" phase node values. The degree of deviation for a prescribed number of successive phase measurements is averaged over this number to obtain a mean phase error. The successive phase deviations are then adjusted by this mean deviation and, based upon the adjusted deviation values, the originally chosen node values may be changed to one of their immediately adjacent nodes. This process is carried out for each phase measurement in the sequence, so as to obtain a phase adjustment factor, by which each of the respective nodes relative to what the measured phase values were originally measured is shifted. This shifting effectively rotates the phase node reference plot by an amount which minimizes the mean square error of the phase node measurements for the prescribed number of phase measurements. The difference between the adjusted node values of the two adjace…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.