Communication terminal for transceiving two frequencies using a common one turn antenna

• US 6,911,876 B2
• Filed: 07/03/2001
• Issued: 06/28/2005
• Est. Priority Date: 08/31/2000
• Status: Expired due to Term

• Current Assignee: SKIDATA AG (Thales SA)
• Original Assignee: SKIDATA AG (Thales SA)
• Inventors: Grabner, Wolfgang
• Primary Examiner(s): Summons, Barbara
• Application Number:
  US10/363,289
• Publication Number:
  US 20030179108A1
• Time in Patent Office: 1,456 Days
• Field of Search: 333/24.R, 333/100, 333/101, 333/129, 333/132, 455/41, 455/59, 455/88, 455/103, 455/500, 342/44, 342/51, 340/825.72, 340/825.73, 343/718, 343/841, 343/842
• US Class Current: 333/24.00R
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles

Abstract

The invention relates to a terminal for communication with data supports which function in a non-contact manner, comprising a transreceiver circuit with two resonant circuits with antenna and condenser for the emitting of two radio frequency fields of different carrier frequencies, whereby the common antenna (A) for both resonant circuits comprises a winding.

Claims

1. A terminal for communication with contactless-type data carriers having transceiving electronics with two resonant circuits with common antenna (A) and capacitor for radiating two radio frequency fields with different carrier frequency, wherein the common antenna (A) for both the resonant circuits comprises a coaxial cable and an antenna shield interrupted in a middle area and has one turn.

2. A terminal according to claim 1, wherein the coaxial cable has an inner conductor cross section of 1 to 5 millimeters.

3. A terminal according to claim 1, wherein the coaxial cable has an inner conductor cross section between 0.5 and 10 millimeters.

4. A terminal for communication with contactless-type data carriers having transceiving electronics with two resonant circuits with common antenna (A) and capacitor for radiating two radio frequency fields with different carrier frequency,

wherein the transceiving electronics has an auxiliary coil (L) disposed so as to be connected in series with the antenna (A) for a low-frequency resonant circuit while being connected in parallel for a high-frequency resonant circuit, and

wherein the common antenna (A) for both the resonant circuits has one turn.

5. A terminal for communication with contactless-type data carriers having transceiving electronics with two resonant circuits with common antenna (A) and capacitor for radiating two radio frequency fields with different carrier frequency,

wherein the transceiving electronics has a switch (S) disposed so as to be connected in series with the antenna (A) for a low-frequency resonant circuit while being connected in parallel for a high-frequency resonant circuit, and

wherein the common antenna (A) for both the resonant circuits has one turn.

6. A terminal according to claim 5, wherein the switch (S) is selected from the group comprising an electromechanical relay, a pin diode, a field-effect transistor (FET), a wave trap, an inductance and a semiconductor relay.