Antenna

• US 20030001788A1
• Filed: 06/28/2002
• Published: 01/02/2003
• Est. Priority Date: 06/28/2001
• Status: Active Grant

• Current Assignee: Excel Engineering Incorporated (Excel Energy Tch Limited), Micro Ft Co., Ltd.
• Original Assignee: Excel Engineering Incorporated (Excel Energy Tch Limited), Micro Ft Co., Ltd.
• Inventors: Fujiwara, Masanao
• Granted Patent: US 6,686,883 B2
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142

Abstract

An antenna capable of being mounted on a compact wireless information communication apparatus is provided, where the antenna can be operated under stable condition without being influenced by a change of directivity and a phenomenon such as a body effect.

A transmission antenna 101 is formed on a transmission-sided board 102 as an electric conducting pattern having a length of ¼(λ/4)±20% of a wavelength, where the transmission-sided board 102 mounts thereon a transmission circuit used in a frequency range defined from 700[MHz] to 3[GHz], and a portion of the transmission antenna, which is longer than, or equal to ⅔ of an entire length of the transmission antenna, owns a width wider than, or equal to λ/400. And, an reception antenna 201 is formed on a reception-sided board 202 as an electric conducting pattern having a length of ¼(k/4)±20% of a wavelength, where the reception-sided board 202 mounts thereon a reception circuit used in a frequency range defined from 700[MHz] to 3[GHz], and a portion of the reception antenna, which is longer than, or equal to ⅔ of an entire length of the reception antenna, owns a width wider than, or equal to λ/400.

Claims

1. An antenna used in a frequency range defined from 700 MHz to 3 GHz wherein:

said antenna is formed on a printed circuit board as an electric conducting pattern having a length of ¼

(λ

/4)±

20% of a wavelength, where said printed circuit board mounts thereon a transmission circuit used in said frequency range; and

a portion of said antenna, which is longer than, or equal to ⅔

of an entire length of said antenna, owns a width wider than, or equal to λ

/400.

2. An antenna as claimed in claim 1 wherein:

said portion of the antenna longer than, or equal to ⅔

of the entire length thereof is separated from either a ground portion or said transmission circuit, which are formed on said printed circuit board, by λ

/400 or longer.

3. An antenna as claimed in claim 2 wherein:

transmission output terminal portions are provided on said antenna and said ground portion, where said transmission output terminal portions are capable of measuring a transmission output from said transmission circuit; and

said antenna is further comprised of a switching portion for switching as to whether or not said antenna is electrically conducted to said transmission circuit.

4. An antenna used in a frequency range defined from 700 MHz to 3 GHz wherein:

said antenna is formed on a printed circuit board as an electric conducting pattern having a length of ¼

(λ

/4)±

20% of a wavelength, where said printed circuit board mounts thereon a reception circuit used in said frequency range; and

a portion of said antenna, which is longer than, or equal to ⅔

of an entire length of said antenna, owns a width wider than, or equal to λ

/400.

5. An antenna as claimed in claim 4 wherein:

said portion of the antenna longer than, or equal to ⅔

of the entire length thereof is separated from either a ground portion or said reception circuit, which are formed on said printed circuit board, longer than, or equal to λ

/800.

6. An antenna as claimed in claim 5 wherein:

reception input terminal portions are provided on said antenna and said ground portion, where said reception input terminal portions are capable of inputting a reception signal into said reception circuit; and

said antenna is further comprised of a switching portion for switching as to whether or not said antenna is electrically conducted to said reception circuit.