Capacitor-loaded type single-pole planar antenna

• US 6,452,551 B1
• Filed: 08/02/2001
• Issued: 09/17/2002
• Est. Priority Date: 08/02/2001
• Status: Active Grant

• Current Assignee: Auden Techno Corp.
• Original Assignee: Auden Techno Corp.
• Inventors: Chen, I-Fong
• Primary Examiner(s): Ho, Tan
• Application Number:
  US09/919,945
• Time in Patent Office: 411 Days
• Field of Search: 343/700.MS, 343/702, 343/745, 343/749, 343/841, 343/895
• US Class Current: 343/700.0MS
• 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
• CPC Class Codes: H01Q 5/335 at the feed, e.g. for impedance matching
• CPC Class Codes: H01Q 5/371 Branching current paths

Abstract

A capacitor-loaded type single-pole planar antenna, the antenna has a base installed on a non-electric conductive housing of a communication equipment with a metal shield inside, the base has a surface of a desired area, a tortuous low band antenna with a total length of ¼λ of 900 MHz is provided on the surface, the low band antenna contains an open circuit end and a feed end, the feed end is driven by an interior RF circuit of the communication equipment, a capacitor and an open stub with a total length of ¼λ of 1800 MHz and functioning as a high band antenna are installed on the tailing end of the low band antenna. Thus a dual-frequency planar antenna which can be directly installed on the surface of the housing of the communication equipment such as a mobile phone in a completely flat mode is accomplished.

Claims

1. A capacitor-loaded type single-pole planar antenna, said antenna has a base which is installed on a non-electric conductive housing of a communication equipment with a metal shield inside, said base has a surface of a desired area, a tortuous low band antenna with a total length of ¼

λ

of 900 MHz is provided on said surface, said low band antenna contains an open circuit end and a feed end, said feed end is driven by an interior RF circuit of said communication equipment, a capacitor and an open stub with a total length of ¼

λ

of 1800 MHz and functioning as a high band antenna are installed on the tailing end of said low band antenna.

2. A capacitor-loaded type single-pole planar antenna as claimed in claim 1, wherein,

said capacitor is installed at a location λ

/16 of said open stub of said high band antenna.

3. A capacitor-loaded type single-pole planar antenna as claimed in claim 2, wherein, said capacitor is one with a minimal capacity value of PF class.

4. A capacitor-loaded type single-pole planar antenna as claimed in claim 1, wherein, said capacitor is one with a minimal capacity value of PF class.

5. A capacitor-loaded type single-pole planar antenna as claimed in claim 1, wherein,

said open stub is installed in a gap space between two confronting bending sections of a serial bending line of said low band antenna.

6. A capacitor-loaded type single-pole planar antenna as claimed in claim 5, wherein,

said capacitor is installed at a location λ

/16 of said open stub of said high band antenna.

7. A capacitor-loaded type single-pole planar antenna as claimed in claim 6, wherein, said capacitor is one with a minimal capacity value of PF class.

8. A capacitor-loaded type single-pole planar antenna as claimed in claim 4, wherein, said capacitor is one with a minimal capacity value of PF class.