Patent · US Expired

Radio telephone and method for operating a radiotelephone in slotted paging mode

US5910944A · kind A · utility

85Cited by
14References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 1997
Grant dateJun 8, 1999
Priority date
Expiry dateFeb 28, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D30/70
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Prior to entry into a low-power sleep mode, a radiotelephone (104) in a radiotelephone system (100) calculates in advance the timing required to wake up selected portions of the radiotelephone and stores the calculated wakeup times in registers (216). Also prior to entry into sleep mode, local timing of the radiotelephone is synchronized to received PN roll boundaries from the radiotelephone system. In the sleep mode, the radiotelephone uses a sleep timer (210) to simulate system timing. When the sleep timer (210) matches the stored wakeup times, the radiotelephone re-activates the selected portions of the radiotelephone, such as an oscillator (116) and a radio frequency portion (109) of an analog front end (108), to exit the sleep mode and reacquire communication with the system. This also permits an early exit from sleep mode, for example to service an interrupt, while maintaining system timing.

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