Patent · US Expired

Ultra-sensitive magnetic field receiver capable of operating in high noise environments

US6476719B2 · kind B2 · utility

8Cited by
10References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 6, 2001
Grant dateNov 5, 2002
Priority date
Expiry dateMar 6, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/707
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The unwanted influence a noise-source environment upon a modulated (e.g., FSK-encoded) magnetic field-based communication system is diminished by a non-modulated AC magnetic field communication scheme that uses a demodulatorless magnetic field detector. When installed in a tag to be tracked by a geolocation system, the demodulatorless detector responds when the tag comes within a prescribed proximity of the field generator producing the non-modulated AC magnetic field. The received signal is downconverted to baseband and processed to detect a valid AC magnetic field tone and indicate whether the tag is within a prescribed proximity of the AC magnetic field source.

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