Spread spectrum conference calling system and method
US5179572A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 17, 1991 |
| Grant date | Jan 12, 1993 |
| Priority date | — |
| Expiry date | Jun 17, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/0332
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A spread-spectrum-conference-calling receiver, for use over a communications channel. At each of a plurality of spread-spectrum transmitters, a transmitter-generic-chip-code generator generates a generic-chip-code signal and a transmitter-message-chip-code generator generates a message-chip-code signal. An EXCLUSIVE-OR gate spread-spectrum processes message data with the message-chip-code signal to generate a spread-spectrum signal. The combiner combines the generic-chip-code signal and the spread-spectrum-processed signal. A plurality of receiver-generic-chip-code generators generate a plurality of replicas of the generic-chip-code signal. Each receiver-generic mixer recovers a carrier signal from one of the plurality of received spread-spectrum-communications signals. A plurality of receiver-message-chip-code generators generate a plurality of replica of the message-chip-code signals. A plurality of receiver-message mixers despread one of the plurality of received spread-spectrum-communications signal as a modulated-data signal. Tracking and acquistion circuits use the recovered carrier signal for synchronizing the replicas of the generic-chip-code signals to the recovered carrie…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.