Fast start-up system for transversal equalizers
US4430743A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 13, 1981 |
| Grant date | Feb 7, 1984 |
| Priority date | — |
| Expiry date | Nov 13, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/03133
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A fast start-up system is disclosed for a transversal equalizer comprising a transmitter capable of generating a periodic symbol sequence with a period L, the auto correlation function of said sequence being 0, except for its center. The system generates and transmits a test signal based upon the generated symbol sequence. A receiver generates the same periodic symbol sequence as that generated in the transmitter in a proper phase relation thereto according to a received signal. The correlation between L sampled values and a sequence obtained by recirculating the periodic symbol sequence for each of consecutive M shifted phases, and for each of M' consecutive shifted phases is calculated. The calculated M+M' correlation values are multiplied by a constant. A discrete Fourier transform is obtained for the M+M' multiplied correlation values at N points equal to or greater than M+M' in number. The values of a predetermined frequency characteristic for frequency points obtained from the discrete Fourier transform are stored. The stored values are then divided by the respective values obtained by the discrete Fourier transform and the inverse discrete Fourier transform of the N divided …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.