Patent · US Expired

Transmitting and receiving circuit for an apparatus for the automatic identification of objects and/or living organisms

US4556883A · kind A · utility

21Cited by
17References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 20, 1982
Grant dateDec 3, 1985
Priority date
Expiry dateDec 20, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S13/825
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Transmitting and receiving circuit for an apparatus for the automatic identification of objects and/or living organisms, including a stationary interrogator and a transponder fastened to the object or living organism to be identified, the interrogator including an energy transmitter, a signal transmitter, a first directional coupler connected to the energy and signal transmitters for receiving outgoing waves from the transmitters and for decoupling a first energy component from the outgoing waves, a first transmitting and receiving antenna, a second directional coupler being connected in series with the first directional coupler and being connected to the first transmitting and receiving antenna for receiving returning waves from the transponder and for decoupling a second energy component from the returning waves, an adjustable attenuator connected to the first directional decoupler for receiving the first energy component, an adjustable phase shifter connected to the adjustable attenuator for receiving the first energy component, a third directional coupler having a first input connected to the adjustable phase shifter for receiving the first energy component, a second input conn…

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