Patent · US Active

Method of preventing collisions between RFID readers in RFID system

US8222997B2 · kind B2 · utility

1Cited by
9References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 7, 2007
Grant dateJul 17, 2012
Priority date
Expiry dateNov 11, 2029

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W84/18
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Disclosed herein is a method of preventing collisions between readers in an RFID system. The method includes a first step of RFID readers selecting transmitting channels by examining channels, a second step of transmitting signals via the selected transmitting channels, a third step of receiving signals via channels having the same frequencies as the selected transmitting channels; a fourth step of determining whether a collision has occurred by examining the status of the signals that are received via the transmitting channels; a fifth step of, if, as a result of the determination at the fourth step, it is determined that a collision between the readers has occurred, repeating the first to fourth steps after delays of random time periods based on a predetermined equation, and a sixth step of, if, as a result of the fourth step, no collision between readers is detected, communicating with the corresponding RFID tags.

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