Radio communication network and method for unobstrusive call interception via data duplication
US5710971A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 1995 |
| Grant date | Jan 20, 1998 |
| Priority date | — |
| Expiry date | Dec 18, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B7/1856
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A digital cellular telecommunication network (30) uses transcoders (50) which vocode voice using a maximal lossy compression algorithm which conserves spectrum usage. A call path for an intercepted call is looped from an outer space satellite (32) network into a terrestrial gateway (34). Compressed call data for each of two half-calls in this call path are duplicated at any of the network nodes and inserted into the opposing half-call. In addition, the compressed call data are decompressed in a gateway transcoder (50), combined in a conference bridge (90), and routed to a monitoring center (60). A subscriber unit (36), a second device (48), and the monitoring center (60) all receive call data which has experienced only one compression/decompression cycle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.