Transmitter-receiver for non-contact IC card system

  • US 5,703,573 A
  • Filed: 01/11/1996
  • Issued: 12/30/1997
  • Est. Priority Date: 01/11/1995
  • Status: Expired due to Term
  • ×
    • Pin Icon | RPX Insight
    • Pin
First Claim
Patent Images

1. A transmitter-receiver used for an interrogator in a non-contact IC card system which transmits and receives signals between the interrogator and a transponder;

  • said transmitter-receiver comprising;

    a distance detecting means for detecting the distance between the interrogator and the transponder; and

    an output control means for controlling the output level of the interrogator in accordance with the signals detected by the distance detecting means, so as to keep the receiving level of the transponder within the range of a given value.

View all claims

    Thank you for your feedback