Cable compensation circuit
US4996497A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 5, 1989 |
| Grant date | Feb 26, 1991 |
| Priority date | — |
| Expiry date | Jun 5, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/14
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Circuitry is disclosed which compensates for magnitude and phase variations in the transfer function of a transmission medium. The medium is characterized by amplitude and phase variations in its transfer function wherein the amplitude variations produce increasing loss in the medium as frequency increases. The circuitry possesses an inverse characteristic to these variations, thereby generating a relatively flat magnitude characteristic for the medium-circuitry combination. The circuitry includes a buffer amplifier that receives a portion of an input signal, a network coupled to the amplifier and having zero-pole pairs in its signal transfer function, and a summer which has both the input signal and the output of the network as inputs. Accordingly, the compensation circuit has an overall transfer function which has fixed poles but adjustable zeros, these zeros being dependent on the amplifier gain and the portion of the input signal applied to the amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.