ADSL receiver high pass filter architecture
US7079646B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 17, 2002 |
| Grant date | Jul 18, 2006 |
| Priority date | — |
| Expiry date | Dec 26, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/1252
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An ADSL receiver HPF architecture 300 that reduces the number of Op Amps below that required for known ADSL receiver HPFs. The ADSL receiver HPF 300 is implemented as an active RC filter to provide a single fifth-order Elliptic filter instead of the more conventional pair of third-order Elliptic filters. Since the HPF Elliptic filter stage having the lowest Q factor is reduced as the order of an Elliptic filter transfer function is increased, a single fifth-order Elliptic filter suitable for use as an ADSL receiver HPF can be implemented using only one Op Amp in the second 2nd-order HPF stage 308. A notch (imaginary zero) is provided by summing of output signals associated with active RC structure state variables. This structure minimizes the number of capacitors while preserving the capability to provide a high Q factor for the first 2nd-order HPF stage 304.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.