§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
EP0427342A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Transmission system

Assignee: Koninklijke Philips NV
•
Filing: 1990-11-06
•
Granted: —
•
Expires: 2010-11-06
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A transmission system comprising an interrogator (1) and a number of transponders (2). The transponders (2) communicate with the interro­gator (1) by means of individual addresses for reading and/or writing of information in the transponders, which admits more than one transponder to be located within the read/write zone of the interrogator. By trans­mitting the start code from the interrogator and giving the transponders opportunity to answer with an address dependent time delay of the reply code and investigating time differences between transmitted and received reply codes in the interrogator, the address of the transponder is deter­mined. The transmission system is suitable for use in connection with identification, for example, personal identification.

Inventors

  • 👤 Stig Rune Johansson

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-30 15:35
CPC Classifications
G; G06; G06K; G06K7/00; G06K7/10; G06K7/10009; G06K7/10019; G06K7/10029; G06K7/10059; G06K17/00; G06K17/0022; G06K7/0008; G07; G07C; G07C9/00; G07C9/20; G07C9/28; G08; G08G; G08G1/00; G08G1/01; G08G1/017

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 154 words
A transmission system comprising an interrogator and a number of transponders, the transponders of which by means of individual addressing may communicate with the interrogator for reading and/or writing of in­formation in the transponders even when more than one transponder is within the read/write zone of the interrogate, characte­rized in that for addressing of a transponder the transmitter/recei­ver unit of the interrogator is arranged to transmit a start code, trans­ponders within the read/write zone by means of the transmitter/receiver unit are arranged to transmit a reply code having a time delay dependent on the address of the transponder as a reply to a detected start code, the interrogator in dependence on the measured time delay of the received reply codes is arranged to determine the addresses for within the read/­write zone replying transponders, whereupon when a transponder in ques­tion has been addressed information transmission may take place between the addressed transponder and the interrogator.
Claim 2
Dependent Claim 154 words
A transmission system comprising an interrogator and a number of transponders, the transponders of which by means of individual addressing may communicate with the interrogator for reading and/or writing of in­formation in the transponders even when more than one transponder is within the read/write zone of the interrogate, characte­rized in that for addressing of a transponder the transmitter/recei­ver unit of the interrogator is arranged to transmit a start code, trans­ponders within the read/write zone by means of the transmitter/receiver unit are arranged to transmit a reply code having a time delay dependent on the address of the transponder as a reply to a detected start code, the interrogator in dependence on the measured time delay of the received reply codes is arranged to determine the addresses for within the read/­write zone replying transponders, whereupon when a transponder in ques­tion has been addressed information transmission may take place between the addressed transponder and the interrogator.
Claim 3
Dependent Claim 107 words
A transmission system as claimed in claim 1, characte­rized in that the interrogator is arranged to determine the addres­ses of the transponders in dependence on the measured time delay of received reply codes and the measured continuos length of the received reply codes, and that the interrogator from the measured continuous length of the received reply codes determines the magnitude of the address regions within which the address for replying transponders is located and by use of the measured time delay determines the addresses included within the respective address region, whereupon the transponders with the addresses included within the respective address regions are addressed for information transmission.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag