Patent · US Expired

Acknowledge back pager with adaptive variable transmitter output power

US4825193A · kind A · utility

98Cited by
5References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 7, 1988
Grant dateApr 25, 1989
Priority date
Expiry dateJan 7, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W84/025
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

An acknowledge back (ack-back) pager is provided for receiving paging signals from a central paging station. The central paging station transmits a group of message signals to a group of ack-back pagers which are addressed as a group. The users of the group of addressed ack-back pagers indicate a response to their respective pagers thus providing ack-back data. The pagers in the group of addressed ack-back pagers then simultaneously transmit back to the central station their ack-back data on different frequency sub-bands, a different frequency sub-band being dynamically allocated to each of the pagers in the group. Each ack-back pager determines whether the paging signals received thereby exhibits a signal level less than a predetermined threshold level. If the paging signals received by a particular ack-back pager exhibit a signal level less than such predetermined threshold level, then the pager transmits back to the central station at a first output power level. Otherwise, the pager transmits at a second ouput power level substantially less than the first output power level. In this manner, the problem of the ack-back signal from a particular pager being so strong at the central…

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