Patent · US Expired

Airtime usage limiting system

US6442406B1 · kind B1 · utility

13Cited by
6References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 1999
Grant dateAug 27, 2002
Priority date
Expiry dateOct 15, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M2215/92
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A call time usage system for a portable telephone allows entering call time usage information into the portable telephone. The limits include limits on total airtime and airtime per call for a specified interval. After the specified interval, the limits are reset. A list of exempt numbers is also stored so that the user can call those exempt numbers even after the limit is exceeded.

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