Amplitude modulated telephone carrier systems
US4087639A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 1977 |
| Grant date | May 2, 1978 |
| Priority date | — |
| Expiry date | Jan 28, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J1/06
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A plural channel amplitude modulated telephone carrier system having a plurality of transmitters to provide for the transmission of a like plurality of frequency division multiplexed, amplitude modulated carrier signals in a common direction along a transmission line to a remote termination of the transmission line, and an automatic carrier level coordination control circuit having a first circuit means for developing a d.c. control signal that varies as a predetermined function of the transmission line length, and a second circuit means connected to the first circuit means for controlling the transmit power of each of the aforesaid carrier signals as a function of its own carrier frequency and as a function of the d.c. control signal. The telephone carrier system may be of the station carrier type and may have two or more plural channel amplitude modulated carrier sub-systems, each having its own transmission line. The automatic carrier level coordination control circuit is designed to be common to two or more of the carrier sub-systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.