Patent · US Expired

Method and system for synchronous code division multiplexed communications

US6215780A · kind A · utility

22Cited by
6References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 17, 1998
Grant dateApr 10, 2001
Priority date
Expiry dateJul 17, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W56/005
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

In a code division multiplexed system, a subscriber unit (260, FIG. 1), which includes a pseudonoise code generator (70), is synchronized with the pseudonoise code generator (220) of a communications node (200). Synchronization between the pseudonoise code generators (70, 220) is achieved through measuring the time delay of a signal transmitted from the communications node (200) to the subscriber unit (260) and advancing the code generator of the subscriber unit in accordance with the time delay. This permits transmissions from the subscriber unit (260) to be received synchronously at the satellite. The synchronization is maintained through the periodic transmission from the communications node (200) to the subscriber unit (260) of a message which commands the subscriber unit (260) to adjust the timing of its pseudonoise code generator. The resulting synchronous code division multiplexed system offers increased capacity over conventional systems.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.