Multi-resonance horizontal-U shaped antenna

• US 5,644,319 A
• Filed: 05/31/1995
• Issued: 07/01/1997
• Est. Priority Date: 05/31/1995
• Status: Expired due to Term

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Chen, Yung Jinn, Lee, Dou-Ken, Wu, Ruey-Beei, Li, Hsueh-Jyh
• Primary Examiner(s): Hajec, Donald T.
• Assistant Examiner(s): PHAN, THO GIA
• Application Number:
  US08/455,916
• Time in Patent Office: 762 Days
• Field of Search: 343/702, 343/829, 343/830
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence

Abstract

A novel design of high frequency hidden hand-held antenna which includes two metal arms above a lower arm of finite ground plane. By properly choosing the lengths of these arms and the separations between them, the bandwidth can be broadened more than 20%. Thus, it is suitable for personal mobile communication applications. A full wave equivalent circuit analytic model is also developed to analyze and optimize the geometrical configuration including the lengths and separations between the arms. Numerical analyses for current distribution on the conductor surface and various antenna characteristics such as input impedance and radiation patterns are computed by the use of the analytical models. Experimental results and numerical computations all confirm that better performance characteristics including broadened antenna bandwidth are achieved by this novel antenna.

Claims

1. A horizontal-U shaped antenna provided for application with a signal transmitting and receiving device, said antenna comprising:

a conductive base plate including two vertically side plates extending upwardly from one edge of said base plate;

two horizontal conductive antenna arms of unequal lengths each connected to a corresponding side plate extending horizontally over said base plate; and

said conductive base plate is further provided to be electrically insulated from said signal transmitting and receiving device whereby a plurality of resonance currents are induced in said conductive base plate, said vertical side plates and said horizontal conductive antenna arms to generate a plurality of antenna resonant frequencies.

2. The antenna of claim 1 wherein:

said two horizontal conductive antenna arms of unequal lengths and said two corresponding side plates connected thereto further are separated by an opening slot.

3. The antenna of claim 2 wherein:

said opening slot further being tapered having a narrower opening near said plates and having an opening which being gradually widened therefrom.

4. The antenna of claim 1 further comprising:

a containing box for containing said signal transmitting and receiving device therein;

said containing box further including an upper cover; and

said base plate being securely attached to and electrically insulated from said upper cover of said containing box.

5. A horizontal-U shaped antenna provided for application with a signal transmitting and receiving device, said antenna comprising:

a conductive base plate including two vertically side plates extending upwardly from one edge of said base plate;

two horizontal conductive antenna arms of unequal lengths each connected to a corresponding side plate extending horizontally over said base plate;

said two horizontal conductive antenna arms of unequal lengths and said two corresponding side plates connected thereto further are separated by an opening slot;

said opening slot further being tapered having a narrower opening near said plates and having an opening which being gradually widened therefrom;

a containing box for containing said signal transmitting and receiving device therein;

said containing box further including an upper cover; and

said base plate being securely attached to and electrically insulated from said upper cover of said containing box and being electrically insulated from said signal transmitting and receiving device whereby a plurality of resonance currents are induced in said conductive base plate, said vertical side plates and said horizontal conductive antenna arms to generate a plurality of antenna resonant frequencies.

6. A method of generating multiple-resonance modes of operation in a horizontal-U shaped antenna including a conductive base plate of length L6 having two vertically side plates extending upwardly from one edge of said base plate and two horizontal conductive antenna arms of unequal lengths L1 and L2 respectively each connected to a corresponding side plate and extending horizontally over said base plate, said method including a step of:

(a) providing an insulation means to said horizontal-U shaped antenna for substantially insulating said antenna from external interference; and

(b) adjusting the lengths of said L1, L2 and L6 whereby L1+L2 and L1+L6 are both approximately half of the wavelength λ

corresponding to a main resonance frequency.

7. A method of generating multiple-resonance mode of operation in a horizontal-U shaped antenna comprising the steps of:

(a) forming a base plate having multiple vertically side plates extending upwardly from one edge of said base plate;

(b) forming multiple horizontal conductive antenna arms corresponding to each of said vertical side plates each being of unequal length and being connected to said corresponding side plate and extending horizontally over said base plate; and

(c) adjusting the lengths of said base plates and each of said horizontal antenna arms for achieving said multiple-resonance mode of operation; and

(d) providing an insulation means to said horizontal-U shaped antenna for substantially insulating said base plate from a ground potential whereby a plurality of resonance currents may be induced in said base plate, said vertical side plates and said horizontal conductive antenna arms to generate a plurality of antenna resonant frequencies.

8. A method of designing a multiple-resonance horizontal-U shaped antenna for application with a signal transmitting and receiving device, wherein said antenna including a base plate having multiple vertically side plates extending upwardly from one edge of said base plate and multiple horizontal conductive antenna arms corresponding to each of said vertical side plates each being of unequal length and being connected to said corresponding side plate and extending horizontally over said base plate wherein said base plate is provided to be electrically insulated from said signal transmitting and receiving device, the method comprising the steps of:

(a) making a preliminary selection of a plurality of geometrical parameters of said antenna;

(b) performing a full wavelength equivalent circuit analysis with said geometrical parameters for said antenna for obtaining several performance variables;

(c) comparing said performance variables with a set of targeted performance variables; and

(d) adjusting the lengths of said base plates and each of said horizontal antenna arms for achieving an optimal design wherein said performance variables being most approximating to said target performance variables.