Digital frequency receiver
US4510601A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1982 |
| Grant date | Apr 9, 1985 |
| Priority date | — |
| Expiry date | Feb 12, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q1/4575
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A digital frequency receiver connected to a processor for the recognition of multifrequency code signals received in signalling time slots and transmitted to the receiver in digital form by at least one time multiplex link. The receiver includes means (MO) for modulating the received signals with signals whose frequency corresponds to a code being used and which are supplied by a digital generator, means (FPB) for low-pass filtering the modulated signals and means (CL) for analyzing the energy contained in the spectrum of the signals received in the neighborhood of the frequencies of the code. The invention is particularly adapted for use in time-switched telephone exchanges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.