Wired microstrip linear array of dipoles

• US 4,071,846 A
• Filed: 06/14/1976
• Issued: 01/31/1978
• Est. Priority Date: 06/14/1976
• Status: Expired due to Term

• Current Assignee: Hughes Aircraft Company (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Oltman, Henry G. Jr.
• Primary Examiner(s): Borchelt, Archie R.
• Assistant Examiner(s): Moore, David K.
• Application Number:
  US05/695,359
• Time in Patent Office: 596 Days
• Field of Search: 343/846, 343/700 MS, 343/854
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 21/062 using dipole aerials; H01Q21/067, H01Q21/068 take precedence
• CPC Class Codes: H01Q 9/065 Microstrip dipole antennas patch antenna H01Q9/0407

Abstract

A microstrip linear array of dipoles is disclosed wherein the dipoles are phased in alternate directions thereby enabling them to be spaced at approximately one-half wavelength intervals along or across a microstrip line instead of the typical one wavelength interval. An additional embodiment includes two linear arrays of oppositely polarized dipoles fed by tributary lines located at either side of a main microstrip line. Alternatively, first and second linear arrays of dipoles are disposed on opposite sides of a circuit board and the dipoles fed by microstrip line that evolves into a balanced two wire line. The ground plane on one side of the circuit board is made to gradually taper to a width equal to the microstrip line on the opposite side at which point the latter is called a two-wire line. Dipoles attached to each terminal of the two-wire line are offset in opposite directions in order to properly phase the currents on each dipole so that the currents flow in the same direction and the pair of dipoles radiates incident power with an omnidirectional pattern similar to a conventional dipole antenna.

Claims

1. A wired microstrip linear array of dipole elements for radiating a signal of a predetermined frequency, said linear array of dipoles comprising a dielectric circuit board having a top side and an underside;

a conductive ground plane disposed over said underside of said circuit board;

a main microstrip line adapted to propagate said signal of said predetermined frequency therealong disposed on the top side of said circuit board;

a plurality of microstrip dipole elements disposed at intervals along a line on the top side of said circuit board, each of said microstrip dipole elements having a center;

a first set of tributary microstrip lines of equal electrical length connected at one wavelength intervals along said main microstrip line to successive alternate ones of said microstrip dipole elements at points offset in a consistent direction from the respective centers thereof; and

a second set of tributary microstrip lines of said equal electrical length connected along said main microstrip line midway between said first set thereof to successive remaining ones of said microstrip dipole elements at points offset in a direction opposite to said consistent direction from the respective centers thereof.

2. The wired microstrip linear array of dipole elements for radiating a signal of a predetermined frequency as defined in claim 1 wherein the respective centers of said microstrip dipole elements always fall within the width of the tributary microstrip line connected thereto.

3. A wired microstrip array of dipole elements for radiating a signal of a predetermined frequency, said array of dipole elements comprising a dielectric circuit board having a top side and an underside;

a conductive ground plane disposed over said underside of said circuit board;

a main microstrip line adapted to propagate said signal of said predetermined frequency therealong disposed on the top side of said circuit board;

first and second pluralities of microstrip dipole elements disposed at intervals along first and second parallel lines on opposite sides of said main microstrip dipole elements having a center;

a first set of tributary microstrip lines of equal electrical length connected at one wavelength intervals along said main microstrip line to successive alternate ones of said first and second pluralities of said microstrip dipole elements at points offset in a consistent direction from the respective centers thereof; and

a second set of tributary microwave lines of said equal electrical length connected along said main microstrip line midway between each line of said first set thereof to successive remaining ones of said first and second pluralities of microstrip dipole elements at points offset in a direction opposite to said consistent direction from the respective centers thereof.

4. A wired microstrip linear array of dipole elements for radiating a signal of a predetermined frequency, said array of dipole elements comprising a dielectric circuit board having a top side and an underside;

a main microstrip line adapted to propagate said signal of said predetermined frequency therealong disposed on the top side of said circuit board;

a first plurality of microstrip dipole elements disposed at intervals along a line on the top side of said circuit board, each of said microstrip dipole elements having a center;

a first set tributary microstrip lines of equal electrical length connected at one wavelength intervals along said main microstrip line to successive alternate ones of said microstrip dipole elements at points offset in a consistent direction from the respective centers thereof;

a second set of tributary microstrip lines of said equal electrical length connected along said main microstrip line midway between said first set thereof to successive remaining ones of said microstrip dipole elements at points offset in a direction opposite to said consistent direction from the respective centers thereof;

conductive ground plane disposed on the underside of said circuit board commencing directly under the respective junctions of said first and second sets of tributary microstrip lines with said first plurality of microstrip dipole elements and tapering outwards along and running the full length of said tributary microstrip lines;

additional conductive ground plane disposed on the underside of said circuit board along said main microstrip line connecting with said ground plane along said tributary microstrip lines; and

a second plurality of microstrip dipole elements corresponding to said first plurality thereof disposed on said underside of said circuit board along said line and connected to the commencement of said ground plane with an offset opposite to that of the respective dipole elements on said top side of said circuit board.

5. A wired microstrip linear array of dipole elements for radiating a signal of a predetermined frequency, said array of dipole elements comprising a circuit board;

a microstrip transmission line of predetermined width substantially less than one-half wavelength at said predetermined frequency disposed longitudinally along said circuit board; and

a plurality of microstrip dipole elements disposed orthogonally across said microstrip transmission line substantially at one-half wavelength intervals at said predetermined frequency, the junction of adjacent dipoles with said microstrip transmission line being offset in opposite directions from the respective centers thereof by an amount less than one-half of said predetermined width.

6. The wired microstrip linear array of dipole elements as defined in claim 5 wherein said circuit board is curved backwards from said microstrip transmission line.

7. A wired microstrip linear array of dipole elements for radiating a signal of a predetermined frequency, said array of dipole elements comprising a circuit board;

a ground plane disposed on one side of said circuit board;

a microstrip line of predetermined width substantially less than one-half wavelength at said predetermined frequency disposed along said circuit board on the side opposite from said one side thereof;

a plurality of microstrip dipole elements disposed orthogonally across said microstrip line at one-half wavelength intervals at said predetermined frequency, the junction of adjacent dipoles with said microstrip line being offset in opposite directions from the respective centers thereof by an amount less than one-half of said predetermined width; and

means coupled to the junction of a dipole with said microwave line for feeding said array.

8. The wired microstrip linear array of dipole elements for radiating a signal of a predetermined frequency as defined in claim 7 wherein said circuit board is curved normal to said microstrip line and away therefrom.