Full duplex transponder system

• US 4,963,887 A
• Filed: 08/29/1989
• Issued: 10/16/1990
• Est. Priority Date: 08/31/1988
• Status: Expired due to Fees

• Current Assignee: Yamatake-Honeywell Company Limited, Yokowo Company Limited
• Original Assignee: Yamatake-Honeywell Company Limited, Yokowo Manufacturing Company Limited
• Inventors: Ishikawa, Ko, Sekiguchi, Fusao, Haruyama, Shinichi, Kawashima, Yoshikazu
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): Hellner, Mark
• Application Number:
  US07/399,869
• Time in Patent Office: 413 Days
• Field of Search: 342/42, 342/44, 342/45, 342/51
• US Class Current: 342/44
• CPC Class Codes: G01S 13/758 using a signal generator powered by the interrogation signal
• 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 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles

Abstract

A full duplex transponder system includes an interrogation apparatus and a transponder apparatus. The transponder apparatus includes a reception antenna for receiving an interrogation signal wave whose carrier wave is phase- or frequency-modulated with an interrogation signal, a demodulator for demodulating the interrogation signal from the interrogation signal wave received by the antenna, a rectifier for rectifying the carrier wave of the interrogation signal wave received by the antenna and outputting a DC power used as a drive power source of the transponder apparatus, a multiplier for generating a predetermined harmonic component from the carrier wave of the interrogation signal wave received by the antenna, a modulator for amplitude-modulating the harmonic component with a response signal, and a transmission antenna for transmitting a response signal wave output from the modulator. The interrogation apparatus includes an oscillator for generating the carrier wave, a modulator for phase- or frequency-modulating the carrier wave generated by the oscillator with an interrogation signal, a transmission antenna for transmitting an interrogation signal wave output from the modulator, a reception antenna for receiving the response signal wave output from the transmission antenna of the transponder apparatus, and a demodulator for demodulating the response signal from the response signal wave received by the reception antenna.

Claims

1. A full duplex transponder system in which interrogation is performed from an interrogation apparatus to a moving unit to be interrogated by using a radio wave, and a transponder apparatus of the moving unit responds to the interrogation, said transponder apparatus comprising:

reception antenna means for receiving an interrogation signal wave whose carrier wave is phase- or frequency-modulated with the interrogation signal,

demodulating means for demodulating the interrogation signal from the interrogation signal wave received by said antenna means,

rectifying means for rectifying the carrier wave of the interrogation signal wave received by said antenna means and outputting a DC power used as a drive power source of said transponder apparatus,

multiplying means for generating a predetermined harmonic component from the carrier wave of the interrogation signal wave received by said antenna means,

modulating means for amplitude-modulating the harmonic component with a response signal, and

transmission antenna means for transmitting a response singal wave output from said modulating means; and

said interrogation apparatus comprising;

oscillating means for generating the carrier wave,

modulating means for phase- or frequency-modulating the carrier wave generated by said oscillating means with an interrogation signal,

transmission antenna means for transmitting an interrogation signal wave output from said modulating means,

reception antenna means for receiving the response signal wave output from said transmission antenna means of said transponder apparatus, and

demodulating means for demodulating the response signal from the response signal wave received by said reception antenna means.

2. A system according to claim 1, wherein the harmonic component is a second harmonic component.