Information-processing apparatus wireless communication system and wireless communication method

• US 20070120674A1
• Filed: 09/29/2004
• Published: 05/31/2007
• Est. Priority Date: 09/30/2003
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Takeuchi, Isao
• Granted Patent: US 7,705,711 B2
• Time in Patent Office: Days
• US Class Current: 340/572.200
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• 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 7/10376 the interrogation device being adapted for being moveable
• CPC Class Codes: H04B 5/0056 for use in interrogation, identification or read/write systems record carriers G06K7/00, G06K19/00; for railways B61L3/12
• CPC Class Codes: H04B 5/77 for interrogation

Abstract

An information-processing apparatus shown in FIG. 4 is a wireless communication apparatus for communicating prescribed data in wireless with a back-scattering communication scheme, in which a tag (10) for receiving a carrier wave signal Sf having a frequency of 2.45 GHz and transmitting response signal Sf (D) obtained by modulating the carrier wave signal Sf based on the data and a tag reader (20) for transmitting a carrier wave signal to the tag (10) and receiving and signal-processing a response composite signal that is returned from the tag (10) are provided. This tag reader (20) has a carrier-wave-compensating circuit (30) that compares a phase of the carrier wave signal in transmitting the carrier wave signal and a phase of the carrier wave signal in receiving the carrier wave signal and eliminates a carrier wave composite signal that is not synchronized with the carrier wave signal in transmitting the carrier wave signal based on a comparison result thereof.

Claims

1. An information-processing apparatus that transmits a carrier wave signal having a prescribed frequency to a signal-responding member of a back-scattering communication scheme and receives and processes a response signal obtained by modulating the carrier wave signal based on prescribed data from the signal-responding member, the apparatus comprising:

a signal-transmitting unit that transmits the carrier wave signal to the signal-responding member; and

a signal-processing unit that receives and processes the response signal scattered from the signal-responding member,

wherein the signal-processing unit is provided with a carrier-wave-compensating circuit, the carrier-wave-compensating circuit comparing a phase of the carrier wave signal in transmitting the carrier wave signal with a phase of the carrier wave signal in receiving the carrier wave signal and eliminating therefrom any carrier wave signal that is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal on the basis of a comparison result thereof.

2. The information-processing apparatus according to claim 1, wherein the carrier-wave-compensating circuit includes:

a phase synchronization detection unit that compares a phase of the carrier wave signal in transmitting the carrier wave signal with a phase of the carrier wave signal in receiving the carrier wave signal and detects a carrier wave signal that is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal; and

an amplitude-controlling unit that eliminates therefrom the carrier wave signal, which is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal, detected in the phase synchronization detection unit.

3. The information-processing apparatus according to claim 2, wherein the amplitude-controlling unit includes:

an amplitude-adjusting circuit that adjusts amplitude of the carrier wave signal, which is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal, detected in the phase synchronization detection unit; and

a calculation circuit that subtracts the carrier wave signal adjusted in its amplitude by the amplitude-adjusting circuit from the carrier wave signal in receiving the carrier wave signal.

4. A wireless communication system that performs a wireless communication of prescribed data with a back-scattering communication scheme, the system comprising:

a signal-responding member that receives a carrier wave signal having a prescribed frequency and transmits a response signal obtained by modulating the carrier wave signal based on the prescribed data; and

an information-processing apparatus having a wireless transmission and reception function, the information-processing apparatus transmitting the carrier wave signal to the signal-responding member and receiving and information-processing the response signal scattered from the signal-responding member,

wherein the information-processing apparatus includes a carrier-wave-compensating circuit that compares a phase of the carrier wave signal in transmitting the carrier wave signal with a phase of the carrier wave signal in receiving the carrier wave signal and eliminates therefrom any carrier wave signal that is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal on the basis of a comparison result thereof.

5. The wireless communication system according to claim 4, wherein the carrier-wave-compensating circuit includes:

a phase synchronization detection unit that compares a phase of the carrier wave signal in transmitting the carrier wave signal with a phase of the carrier wave signal in receiving the carrier wave signal and detects a carrier wave signal that is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal; and

an amplitude-controlling unit that eliminates therefrom the carrier wave signal, which is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal, detected in the phase synchronization detection unit.

6. The wireless communication system according to claim 5, wherein the amplitude-controlling unit includes:

an amplitude-adjusting circuit that adjusts amplitude of the carrier wave signal, which is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal, detected in the phase synchronization detection unit; and

a calculation circuit that subtracts the carrier wave signal adjusted in its amplitude by the amplitude-adjusting circuit from the carrier wave signal in receiving the carrier wave signal.

7. The wireless communication system according to claim 4, wherein the signal-responding member is used with it being attached to a prescribed object to be specified.

8. The wireless communication system according to claim 4, wherein the signal-responding member comprises:

an antenna body that receives the carrier wave signal;

a memory unit that stores the data;

an amplitude modulation unit that performs amplitude modulation on the carrier wave signal based on the data read out of the memory unit; and

a power-supplying unit that supplies induced power to the memory unit and the amplitude modulation unit, the induced power being induced based on the carrier wave signal received by the antenna body.

9. A wireless communication method of a back-scattering communication scheme comprising the steps of:

attaching to an object to be specified a signal-responding member that receives a carrier wave signal having a prescribed frequency and transmits a response signal obtained by modulating the carrier wave signal based on the prescribed data;

transmitting the carrier wave signal to the signal-responding member attached to the object; and

receiving and signal-processing the response signal return from the signal-responding member,

wherein a phase of the carrier wave signal in transmitting the carrier wave signal with a phase of the carrier wave signal in receiving the carrier wave signal are compared and a carrier wave signal that is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal is eliminated on the basis of a comparison result thereof.

10. The wireless communication method according to claim 9, wherein a phase of the carrier wave signal in transmitting the carrier wave signal with a phase of the carrier wave signal in receiving the carrier wave signal are compared;

a carrier wave signal that is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal; and

the detected carrier wave signal, which is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal is eliminated therefrom.

11. The wireless communication method according to claim 10, wherein amplitude of the carrier wave signal, which is not synchronized with the phase of the carrier wave signal in transmitting the carrier wave signal is adjusted;

and the carrier wave signal thus adjusted in its amplitude is subtracted from the carrier wave signal in receiving the carrier wave signal.