Radiotelephone communications system
US4268722A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 1979 |
| Grant date | May 19, 1981 |
| Priority date | — |
| Expiry date | Sep 6, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q11/0407
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone system for providing communications between mobile radiotelephones, portable radiotelephones and landline telephones includes a land-line telephone system including a land-line switching network for providing communication paths for land-line telephones and a mobile radiotelephone system for providing communications paths for mobile and portable radiotelephones. The mobile radiotelephone system includes a digital switching network, base stations, and PCM analog-to-digital (A/D) and digital-to-analog (D/A) converters interposed between the base stations and the digital switching network and between the land-line switching network and the digital switching network. Analog ports are interfaced by the PCM A/D and D/A converters to incoming and outgoing serial bit streams coded according to pulse-code-modulation (PCM) techniques standardized for telecommunications systems by the International Telegraph and Telephone Consultative Committee (CCITT). The digital switching network receives the incoming serial PCM bit streams and provides the outgoing serial PCM bit streams so that telephone calls are automatically routed between the calling and called parties in the telephone sy…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.