Transmitting and receiving loop antenna with reactive loading

• US 4,080,603 A
• Filed: 07/12/1976
• Issued: 03/21/1978
• Est. Priority Date: 07/12/1976
• Status: Expired due to Term

• Current Assignee: Howard Belmont Moody
• Original Assignee: Howard Belmont Moody
• Inventors: Moody, Howard Belmont
• Primary Examiner(s): Lieberman, Eli
• Application Number:
  US05/704,251
• Time in Patent Office: 617 Days
• Field of Search: 343/744, 343/752, 343/845, 343/846, 343/712
• US Class Current: 343/712
• CPC Class Codes: H01Q 1/3275 mounted on a horizontal surface of the vehicle, e.g. on roof, hood, trunk
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 9/265 Open ring dipoles; Circular dipoles

Abstract

The disclosure relates to an antenna system for C.B. radio use which is mounted upon a metallic base, such as the roof of an automobile, the antenna having the S-shape or Greek-key design configuration, the antenna being mounted at one end of the base through an insulating medium, the one end being coupled to a plate on the insulating medium which forms a capacitor with the insulating medium and the metallic base of fixed predetermined value. A variable capacitor is also formed between end extension of the plate and the free end of the antenna.

Claims

1. An antenna system which comprises:

a. an electrically conductive base surface, and

b. an antenna mounted on said base surface, including;

c. an electrically insulating layer disposed on said base surface,

d. an electrically conductive plate positioned on said insulating layer remote from said base surface to form a capacitor therewith, said antenna being coupled at one end to said plate,

e. said antenna having a plurality of S-shaped regions disposed about its continuous perimeter, and

f. means coupled to said base for providing a variable capacitance between said antenna and said base surface.

2. A system as set forth in claim 1, wherein said base surface is the exterior surface of an automobile.

3. A system as set forth in claim 2, wherein the perimeter of said antenna is substantially circular.

4. A system as set forth in claim 1, wherein said means coupled to said base includes said base surface, electrically insulating means having apertures therein positioned on said base surface, electrically conductive means coupled to said one end of said antenna and having apertures alinable with said apertures of said electrically insulating means, said electrically insulating means and electrically conductive means being rotatable relative to each other.

5. A system as set forth in claim 2 wherein said means coupled to said base includes said base surface, electrically insulating means having apertures therein positioned on said base surface, electrically conductive means coupled to said one end of said antenna and having apertures alinable with said apertures of said electrically insulating means, said electrically insulating means and electrically conductive means being rotatable relative to each other.

6. A system as set forth in claim 3, wherein said means coupled to said base includes said base surface, electrically insulating means having apertures therein positioned on said base surface, electrically conductive means coupled to said one end of said antenna and having apertures alinable with said apertures of said electrically insulating means, said electrically insulating means and electrically conductive means being rotatable relative to each other.