Patent · US Active

Systems and methods for an RF nulling scheme in RFID

US7787837B2 · kind B2 · utility

9Cited by
2References
25Claims
0Family size

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Inventor

Key dates

Filing dateSep 14, 2006
Grant dateAug 31, 2010
Priority date—
Expiry dateFeb 13, 2029

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/525
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Systems and methods for an RF nulling scheme are provided. An RF nulling scheme can minimize the level of unwanted RF signal reflections entering the receiver without attenuating the desired signal response from an RFID tag. In one aspect of the RF nulling scheme a synthesizer signal can be split between a main path and a nulling path. In the nulling path the signal from the splitter can be routed through an electronically variable phase shifter and variable gain amplifier to create a nulling signal. The nulling signal can cancel the unwanted reflected signal. The phase or amplitude of the nulling signal can then be adjusted to improve cancellation as necessary.

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