Voice, data or both over one telephone line in a T-1 carrier system
US4730312A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 21, 1986 |
| Grant date | Mar 8, 1988 |
| Priority date | — |
| Expiry date | Feb 21, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/1647
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A standard T-1 span is connected to a digital central office or remote terminal. Telephone equipment for such a T-1 span defines a superframe format with each frame of the twelve frames of a superframe having twenty-four eight-bit position time slots. Telephone system signalling requires T-1 signalling bits be located in the least significant bit position of each time slot in every sixth frame. In the disclosed system, simultaneous digitized voice and data share a single time slot for transmission along with the T-1 signalling bits in that time slot. In order to achieve the additional capability, the disclosed system employs least and next-to-least digitized voice bit swapping and a data bit occupying the space of the swapped least significant digitized voice bit, which bit is deleted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.