Patent · US Expired

Induction field coupled transmission system incorporating a passive transmitter

US5542118A · kind A · utility

3Cited by
7References
16Claims
0Family size

Inventor

Key dates

Filing dateSep 13, 1994
Grant dateJul 30, 1996
Priority date
Expiry dateSep 13, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K19/0723
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A remote, unpowered passive transmitter has a tank circuit, a coil and capacitor. The capacitor is variable to vary the frequency of the tank. This is coupled to a receiver having a hybrid splitter. With four ports, two balanced, opposing ports connect to two lines terminating in line impedance. The tank couples into one of the two line so that a difference signal is formed and output. Line loading forms a signal indicating tank frequency.

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