Patent · US Expired

Cellular radiotelephone system with dropped call protection

US4811380A · kind A · utility

62Cited by
24References
32Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 29, 1988
Grant dateMar 7, 1989
Priority date
Expiry dateJan 29, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W36/38
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

An improved cellular telephone communication system is described having operational steps which prevent a call from being dropped due to a radiotelephone not receiving a handoff instruction from its host base site. The system includes a switch controller for determining that the radiotelephone requires a handoff from a first base site coverage area to a second base site coverage area and for communicating a handoff message to the associated first and second base site equipment. The first base site equipment then transmits the handoff message to the radiotelephone. If the radiotelephone does not receive the message, it determines that the call has been lost, siezes a signalling channel from the second base site, and requests, via the second base site a call reconnection by transmitting a special message. The second base site then informs the radiotelephone of the handoff instruction and the handoff is completed with a successful reconnection of the call.

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