Circuit and method for equalization of signals received over a communication system transmission line
US6531931B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1999 |
| Grant date | Mar 11, 2003 |
| Priority date | — |
| Expiry date | May 28, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/145
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A circuit and method for equalization of a communication signal received over a communication system transmission line using switched filter characteristics. Equalization for frequency-independent and frequency-dependent attenuation of the communication signal is accomplished with a linear equalization channel which includes an input biasing circuit which provides a common input signal to two parallel amplifier paths. One path includes a wideband, fixed-gain, frequency-independent amplifier stage. The other path is a wideband multiplier amplifier stage in series with a wideband, frequency-dependent amplifier stage having a switchable high-pass characteristic. The outputs of the fixed-gain wideband frequency-independent amplifier stage and wideband, frequency-dependent amplifier stage having a switchable high-pass characteristic are both tied in common to the input of a wideband gain buffer amplifier stage, which has a switchable high-frequency boost frequency response characteristic. Filter characteristic for the frequency-dependent amplifier stages are selected to accommodate predetermined ranges of cable lengths. The amplifier stages are formed as simple n-MOS transconductance di…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.