Wireless communication circuit, wireless communication terminal and method, recording medium, and program

• US 7,031,662 B2
• Filed: 10/02/2003
• Issued: 04/18/2006
• Est. Priority Date: 10/22/2002
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Ericsson Mobile Communications Japan Incorporated (Sony Group Corp.)
• Inventors: Arisawa, Shigeru, Suzuki, Mamoru, Kusakabe, Susumu, Mizusawa, Nishiki, Nagano, Tomonori, Nakazawa, Takaki
• Primary Examiner(s): Nguyen, Simon
• Application Number:
  US10/676,019
• Publication Number:
  US 20040121739A1
• Time in Patent Office: 929 Days
• Field of Search: 455/76, 455/78, 455/81, 455/88, 455/558, 455/63.1, 455/114, 455295-296, 375/346
• US Class Current: 455/63.1
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: H04B 1/3833 Hand-held transceivers
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

In a communication terminal that is capable of carrying out communications based on a plurality of communication standards, for example, a cellular phone, information representing a reception carrier frequency of a wireless channel being received by a cellular-phone functional block is output from a CPU to a contactless-IC-card-reader/writer functional block. In the contactless-IC-card-reader/writer functional block, a controller controls a switching circuit to switch a transmission carrier frequency being used so that harmonic components of an electromagnetic wave radiated from a coil antenna will not work as an electromagnetic-interference wave that affects reception sensitivity of the cellular-phone functional block.

Claims

1. A wireless communication circuit comprising:

receiving means for receiving a first electromagnetic wave having a first carrier frequency for communication based on a first wireless communication standard;

transmitting means for transmitting a second electromagnetic wave having a second carrier frequency for communication based on a second wireless communication standard; and

controlling means for controlling the second carrier frequency so that a frequency of an electromagnetic-interference wave that is generated by transmission of the second electromagnetic wave by the transmitting means does not fall within a predetermined frequency range with which reception sensitivity of the receiving means to the first electromagnetic wave is degraded.

2. A wireless communication circuit according to claim 1, further comprising a plurality of generating means for generating respectively different frequencies, wherein the controlling means controls the second carrier frequency by selecting one of the plurality of generating means.

3. A wireless communication circuit according to claim 1, further comprising generating means for generating different frequencies in accordance with change in a resonance frequency of an oscillator, wherein the controlling means controls the second carrier frequency by changing the resonance frequency.

4. A wireless communication circuit according to claim 1, further comprising generating means for generating different frequencies in accordance with change in a load capacitance of an oscillator, wherein the controlling means controls the second carrier frequency by changing the load capacitance.

5. A wireless communication circuit according to claim 1, wherein the controlling means controls the second carrier frequency by using a clock used by the receiving means or a real-time clock for timekeeping as a reference clock for a phase-locked loop circuit, and setting a frequency-dividing number for the phase-locked loop circuit.

6. A wireless communication circuit according to claim 1, wherein the controlling means determines that the reception sensitivity to the first electromagnetic wave is degraded by the electromagnetic-interference wave when the first carrier frequency has a value in a vicinity of an integer multiple of the second carrier frequency, and controls the second carrier frequency.

7. A wireless communication circuit according to claim 1, wherein the controlling means determines that the reception sensitivity to the first electromagnetic wave is degraded by the electromagnetic-interference wave when communication based on the first wireless communication standard is being carried out, and controls the second carrier frequency.

8. A wireless communication terminal comprising:

receiving means for receiving a first electromagnetic wave having a first carrier frequency for communication based on a first wireless communication standard;

transmitting means for transmitting a second electromagnetic wave having a second carrier frequency for communication based on a second wireless communication standard; and

controlling means for controlling the second carrier frequency so that a frequency of an electromagnetic-interference wave that is generated by transmission of the second electromagnetic wave by the transmitting means does not fall within a predetermined frequency range with which reception sensitivity of the receiving means to the first electromagnetic wave is degraded.

9. A wireless communication terminal according to claim 8, further comprising a plurality of generating means for generating respectively different frequencies, wherein the controlling means controls the second carrier frequency by selecting one of the plurality of generating means.

10. A wireless communication terminal according to claim 8, further comprising generating means for generating different frequencies in accordance with change in a resonance frequency of an oscillator, wherein the controlling means controls the second carrier frequency by changing the resonance frequency.

11. A wireless communication terminal according to claim 8, further comprising generating means for generating different frequencies in accordance with change in a load capacitance of an oscillator, wherein the controlling means controls the second carrier frequency by changing the load capacitance.

12. A wireless communication terminal according to claim 8, wherein the controlling means controls the second carrier frequency by using a clock used by the receiving means or a real-time clock for timekeeping as a reference clock for a phase-locked loop circuit, and setting a frequency-dividing number for the phase-locked loop circuit.

13. A wireless communication terminal according to claim 8, wherein the controlling means determines that the reception sensitivity to the first electromagnetic wave is degraded by the electromagnetic-interference wave when the first carrier frequency has a value in a vicinity of an integer multiple of the second carrier frequency, and controls the second carrier frequency.

14. A wireless communication terminal according to claim 8, wherein the controlling means determines that the reception sensitivity to the first electromagnetic wave is degraded by the electromagnetic-interference wave when communication based on the first wireless communication standard is being carried out, and controls the second carrier frequency.

15. A wireless communication method comprising:

a receiving step of receiving a first electromagnetic wave having a first carrier frequency for communication based on a first wireless communication standard;

a transmitting step of transmitting a second electromagnetic wave having a second carrier frequency for communication based on a second wireless communication standard; and

a controlling step of controlling the second carrier frequency so that a frequency of an electromagnetic-interference wave that is generated by transmission of the second electromagnetic wave in the transmitting step does not fall within a predetermined frequency range with which reception sensitivity to the first electromagnetic wave in the reception step is degraded.

16. A recording medium having recorded thereon a computer-readable program that allows a computer to execute processing for receiving a first electromagnetic wave having a first carrier frequency for communication based on a first wireless communication standard, and processing for transmitting a second electromagnetic wave having a second carrier frequency for communication based on a second wireless communication standard, the program comprising a controlling step of controlling the second carrier frequency so that a frequency of an electromagnetic-interference wave that is generated by transmission of the second electromagnetic wave does not fall within a predetermined frequency range with which reception sensitivity to the first electromagnetic wave is degraded.

17. A computer-readable program that allows a computer to execute processing for receiving a first electromagnetic wave having a first carrier frequency for communication based on a first wireless communication standard, and processing for transmitting a second electromagnetic wave having a second carrier frequency for communication based on a second wireless communication standard, the program comprising a controlling step of controlling the second carrier frequency so that a frequency of an electromagnetic-interference wave that is generated by transmission of the second electromagnetic wave does not fall within a predetermined frequency range with which reception sensitivity to the first electromagnetic wave is degraded.