Patent · US Expired

Soft handoff in a cellular telecommunications system

US5722074A · kind A · utility

92Cited by
4References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 14, 1996
Grant dateFeb 24, 1998
Priority date
Expiry dateJun 14, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W56/00
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A soft handoff in a cellular telecommunications system in which a user mobile station relays user communication radio signals via at least two base stations to and from a controlling mobile exchange connected to another system user. The relay of user information signals is performed by using digital frames carried on digital transmission connections in the uplink and downlink directions. The differential delay of the two or more terrestial routes between the base stations and the exchange is compensated by a novel time alignment procedure. Each of the base stations sends time alignment request to the mobile exchange which performs the frame time alignment of the downlink transmissions by taking into account TA requests from all base stations.

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