Wireless Communication Apparatus and Operating Frequency Control Method of Power Conversion Apparatus

• US 20070195722A1
• Filed: 08/24/2006
• Published: 08/23/2007
• Est. Priority Date: 08/26/2005
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Hiramoto, Toshikazu
• Granted Patent: US 7,957,488 B2
• Time in Patent Office: Days
• US Class Current: 370/318
• CPC Class Codes: H04B 15/06 by local oscillators of receivers

Abstract

In order to decrease a negative influence on other electric apparatuses because of conduction noise occurring from a wireless communication apparatus along with preventing increasing cost and an increase in size of communication module, the wireless communication apparatus includes: a high accuracy oscillator which is applied for communication operation of the wireless communication portion, and which generates a predetermined clock signal which becomes a predetermined frequency by dividing at a predetermined division rate; a low accuracy oscillator which has a lower accuracy than the high accuracy oscillator, and which generates a first clock signal close to the predetermined frequency; a frequency divider which divides the operation clock signal at a predetermined division rate, and generates a second clock signal; and a control portion which conducts a switching operation in which the operation clock signal supplied to the power conversion apparatus is switched to the second clock signal when the wireless communication portion receives an annunciation signal, and to the first clock signal when receiving of the annunciation signal is suspended.

Claims

1. A wireless communication apparatus comprising:

a power conversion apparatus which operates a switching operation based on an operation frequency regulated in accordance with an operation clock signal to convert power supplied externally to a DC power for an inside power source;

a wireless communication portion;

a high accuracy oscillator which is applied for communication operation of the wireless communication portion, and which generates a predetermined clock signal which becomes a predetermined frequency by dividing at a predetermined division rate;

a low accuracy oscillator which has a lower accuracy than the high accuracy oscillator, and which generates a first clock signal close to the predetermined frequency;

a frequency divider which divides the predetermined clock signal at a predetermined division rate, and generates a second clock signal; and

a control portion which conducts a switching operation in which the operation clock signal supplied to the power conversion apparatus is switched to the second clock signal when the wireless communication portion receives an annunciation signal, and to the first clock signal when receiving of the annunciation signal is suspended.

2. A wireless communication apparatus according to claim 1, wherein the control portion stops oscillation operation of the high accuracy oscillator upon suspending receiving of the annunciation signal.

3. A wireless communication apparatus according to claim 1, wherein the control portion transits to a sleeping state upon suspending receiving of the signal.

4. A wireless communication apparatus according to claim 1, wherein the low accuracy oscillator is a RC oscillator.

5. A wireless communication apparatus according to claim 1, wherein the high accuracy oscillator is a TCXO (Temperature Compensated Crystal Oscillator).

6. An operation frequency control method of a power conversion apparatus in a wireless communication apparatus which includes:

the power conversion apparatus which operates a switching operation based on an operation frequency regulated in accordance with an operation clock signal to convert power supplied externally to a DC power for an inside power source; and

a wireless communication portion which communicates with a base station, the operation frequency control method comprising the steps of;

a first step of generating with high accuracy a predetermined clock signal which is applied for communication operation of the wireless communication portion, and which has a predetermined frequency by dividing at a predetermined division rate;

a second step of generating a first clock signal which has a lower accuracy than the first step and which is close to the predetermined frequency;

a third step of generating a second clock signal by dividing the predetermined clock signal at a predetermined division rate; and

a fourth step of conducting a switching operation in which the operation clock signal supplied to the power conversion apparatus is switched to the second clock signal when the wireless communication portion receives an annunciation signal from the base station and to the first clock signal when receiving of the annunciation signal is suspended.