Wireless communication terminal having an impedance matching circuit

• US 7,603,150 B2
• Filed: 10/17/2005
• Issued: 10/13/2009
• Est. Priority Date: 10/21/2004
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Takahashi, Shin
• Primary Examiner(s): Eng; George
• Assistant Examiner(s): FARAGALLA, MICHAEL A
• Application Number:
  US11/252,985
• Publication Number:
  US 20060105820A1
• Time in Patent Office: 1,457 Days
• Field of Search: 455/575.7, 455/550.1, 455/572, 455/574, 455/575.1, 455/575.3, 455/575.4, 455/575.5, 370318-320, 330/298
• US Class Current: 455/575.3
• CPC Class Codes: H01Q 1/242 specially adapted for hand-held use
• CPC Class Codes: H04M 1/0214 Foldable telephones, i.e. with body parts pivoting to an open position around an axis parallel to the plane they define in closed position combined with translation movement H04M1/0235
• CPC Class Codes: H04M 1/03 Constructional features of telephone transmitters or receivers, e.g. telephone hand-sets
• CPC Class Codes: H04M 2250/16 including more than one display unit
• CPC Class Codes: H04M 2250/52 including functional features of a camera

Abstract

A wireless communication terminal able to suppress deterioration of antenna characteristics due to opening/closing of a terminal, that is, wireless communication terminal having, a first housing; a second housing connected so that both housings can be opened and closed with respect to each other; an antenna arranged in one housing of the first housing and second housing; an electric signal/audio converting portion arranged in the other housing of the first housing and second housing; and an audio processing unit for performing audio processing of the electric signal/audio converting portion, wherein the antenna is arranged facing the vicinity of the electric signal/audio converting portion when the first housing and second housing are in the closed state and is arranged away from the electric signal/audio converting portion when the housings are in the opened state, and a matching circuit for matching an impedance of the antenna is arranged between the audio processing unit and the electric signal/audio converting portion.

Claims

1. A wireless communication terminal comprising:

a first housing;

a second housing connected to the first housing so that the housings open and close with respect to each other;

an antenna arranged in one housing of the first housing and second housing;

an electric signal/audio converting portion arranged in the other housing of the first housing and second housing; and

an audio processing unit for performing audio processing of the electric signal/audio converting portion, wherein

the antenna is arranged facing the vicinity of the electric signal/audio converting portion when the first housing and second housing are in the closed state and is arranged away from the electric signal/audio converting portion when the housings are in the opened state, and

a matching circuit for matching an impedance of the antenna is arranged between the audio processing unit and the electric signal/audio converting portion,

wherein the terminal further comprises;

an open/close detection unit for detecting whether the first housing and second housing are in the opened state or the closed state,

a first signal line connected to the electric signal/audio converting portion and having the matching circuit arranged therein,

a second signal line connected to the electric signal/audio converting portion and not having the matching circuit arranged therein, and

a switch unit for switching a signal line connected to the audio processing unit between the first signal line and the second signal line, and

the switch unit switches the signal line based on detection results of the opening/closing detection unit.

2. A wireless communication terminal as set forth in claim 1, wherein the matching circuit is set so as to operate when the first housing and second housing are in the closed state.

3. A wireless communication terminal as set forth in claim 1, wherein the matching circuit is set so as to operate with respect to a communication frequency bandwidth and not operate with respect to an audio frequency bandwidth.

4. A wireless communication terminal as set forth in claim 1, wherein the matching circuit is set so as to operate when the first housing and second housing are in the closed state.

5. A wireless communication terminal as set forth in claim 1, wherein the matching circuit is set so as to operate with respect to a communication frequency bandwidth and not operate with respect to an audio frequency bandwidth.