Meander line antenna

• US 7,205,954 B2
• Filed: 06/21/2005
• Issued: 04/17/2007
• Est. Priority Date: 02/01/2005
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Kai, Manabu, Maniwa, Toru, Yamagajo, Takashi
• Primary Examiner(s): Wimer; Michael C.
• Application Number:
  US11/156,532
• Publication Number:
  US 20060170606A1
• Time in Patent Office: 665 Days
• Field of Search: 343/713, 343/795, 343/803, 343/806
• US Class Current: 343/803
• CPC Class Codes: G06K 19/0726 the arrangement including a circuit for tuning the resonance frequency of an antenna on the record carrier
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: H01Q 1/22 by structural association with other equipment or articles
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 9/26 with folded element or elements, the folded parts being spaced apart a small fraction of operating wavelength resonant loop antennas H01Q7/00
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

A meander line antenna formed in the shape of meander is disclosed. The meander line antenna includes a bottom half section that is constituted by a folded conductive pattern of a folded dipole antenna, and includes a feeding point for mounting an IC chip at the central part; a top half section that is constituted by a folded conductive pattern of a folded dipole antenna shaped like the bottom half section; and a frequency adjusting section consisting of connecting conductive patterns arranged at an interval corresponding to a desired frequency centering on the feeding point, the connecting conductive patterns connecting the bottom half section and the top half section. The connecting conductive patterns can be cut off, and the folded conductive pattern outside of the cut-off connecting conductive patterns can be removed.

Claims

1. A meander line antenna formed by folding a conductor pattern of a folded dipole antenna in the shape of a meander, comprising:

a bottom half section that includes a folded conductor pattern, and a feeding point arranged at approximately a central part of the bottom half section;

a top half section that includes a folded conductor pattern shaped like the folded conductor pattern of the bottom half section; and

a frequency adjusting section constituted by connecting conductor patterns and configured to connect the bottom half section and the top half section at intervals corresponding to desired resonance frequencies, the intervals centering on the feeding point,

wherein connecting conductor patterns of the frequency adjusting section corresponding to a desired frequency remain intact, connecting conductor patterns inside of the intact connecting conductor patterns are removed, and the folded conductor patterns outside of the intact connecting conductor patterns are removed.

2. A meander line antenna formed by folding a conductor pattern of a folded dipole antenna in the shape of a meander, comprising:

a bottom half section that includes a folded conductor pattern, and a feeding point arranged at approximately a central part of the bottom half section;

a top half section that includes a folded conductor pattern shaped like the folded conductor pattern of the bottom half section;

a frequency adjusting section constituted by connecting conductor patterns and configured to connect the bottom half section and the top half section at intervals corresponding to desired resonance frequencies, the intervals centering on the feeding point; and

a fine-tuning section that includes a plurality of short-circuit conductor patterns that connect certain countering conductor patterns of the top half section at predetermined intervals, the certain countering conductor patterns being located at a position that counters the feeding point formed in the bottom half section.

3. A meander line antenna comprising:

conductor patterns of a folded dipole antenna, folded in a meander shape, said conductor patterns comprising;

a first part including a folded conductor pattern and a central region having a feeding point;

a second part including a folded conductor pattern having the same shape, length and width as the folded conductor pattern of the first part;

a frequency adjusting part formed by connecting conductor patterns configured to connect the first and second parts at intervals with reference to the feeding point and correspond to selecting frequencies,

wherein the connecting conductor patterns of the frequency adjusting part corresponding to a selecting frequency remain intact, while connecting conductor patterns arranged on an inner side of the intact connecting conductor patterns and the folded conductor patterns arranged on an outer side of the intact connecting conductor patterns are removed.

4. The meander line antenna as claimed in claim 3, further comprising:

a fine-tuning part including a plurality of short-circuit conductor patterns configured to connect conductor patterns of the second part, confronting the feeding point, at predetermined intervals.

5. The meander line antenna as claimed in claim 3, wherein selected connecting conductor patterns of the frequency adjusting part are removable depending on a selecting frequency together with the folded conductor patterns arranged on an outer side of the connecting conductor patterns other than the selected connecting conductor patterns.