Amplitude/frequency correcting device and corresponding frequency equalizer
US5789993A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 1997 |
| Grant date | Aug 4, 1998 |
| Priority date | — |
| Expiry date | Feb 11, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/145
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A device (1) for correcting the amplitude/frequency characteristic of an input signal (FI), particularly from transmission cables (40), having a minimal frequency f1, a center frequency f0 and a maximal frequency f2, the input signal (FI) having an attenuation as a function of frequency characteristic that increases between f1 and f2, the correction device (1) supplying a corrected output signal (). The correction device includes two cascaded filters (41, 42), the first of the filters receiving the input signal (FI) and supplying a filtered signal (SFI) to the second of the filters, the second of the filters supplying the corrected output signal (). One of the filters is a band-stop filter (41) having a center frequency f3 less than or equal to f1, the other of the filters being a band-pass filter (42) having a center frequency f4 greater than or equal to f2. The center frequencies f3 and f4 satisfy the equation: EQU f3.times.f4=f0.sup.2 The filters (41, 42) are of the same order and their Q-factors are adjusted by a control signal (SC) from a control device (43).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.