ISDN-to-ISDN communication via satellite microwave radio frequency communications link
US5412660A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1993 |
| Grant date | May 2, 1995 |
| Priority date | — |
| Expiry date | Sep 10, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q2213/333
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An embodiment of the present invention includes a plurality of portable satellite terminals (PSTs) and a network control unit (NCU) in mutual communication by a communications satellite. Integrated services digital network (ISDN) basic rate interfaces (BRI) are provided at each PST and NCU such that commercially available equipment may be connected and link access procedure D-channel (LAPD) protocols are supported end-to-end. CCITT Recommendation V.42 link access procedure-modem (LAPM) with the selective frame reject option is used to carry whole LAPD frames within the information fields of LAPM frames over the satellite link. Protocol conversion units are employed at each PST and NCU to convert LAPD to LAPM and back again.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.