Axially arrayed helical antenna

• US 5,587,719 A
• Filed: 02/04/1994
• Issued: 12/24/1996
• Est. Priority Date: 02/04/1994
• Status: Expired due to Term

• Current Assignee: Orbital Sciences Corporation (Northrop Grumman Corporation)
• Original Assignee: Orbital Sciences Corporation (Northrop Grumman Corporation)
• Inventors: Steffy, David A.
• Primary Examiner(s): Wimer, Michael C.
• Application Number:
  US08/191,247
• Time in Patent Office: 1,054 Days
• Field of Search: 343/725, 343/895, 343/844, 343/853, 343/881, 343/893
• US Class Current: 343/895
• CPC Class Codes: B64G 1/22 Parts of, or equipment specially adapted for fitting in or to, cosmonautic vehicles
• CPC Class Codes: H01Q 1/288 Satellite antennas
• CPC Class Codes: H01Q 11/08 Helical antennas

Abstract

The present invention comprises an axially arrayed helical antenna system adapted for use in a variety of broadcasting or receiving stations including a low Earth orbiting communication satellite station. The helical antenna array comprises a plurality of antenna structures each including at least one helical antenna element coaxially mounted on a common mounting structure with a separating distance between them. Each element is electromagnetically coupled to a corresponding element of the subsequent antenna structure in the array to form a separate, isolated antenna. A feeding means is included for supplying appropriately phase shifted signals to the elements that comprise each antenna. In addition, in accordance with the invention, additional independent antennas or other equipment or payload can be deployed in the separating distance between the arrayed antenna structures.

Claims

1. An antenna system comprising:

a plurality of antenna structures which include a first and second antenna element, said first antenna element having at least one helical conductive element wound in a left hand direction around a common axis, and said second antenna element having at least one helical conductive element wound in a right hand direction around said common axis, said antenna structures being arrayed axially spaced from one another along said common axis;

feeding means for feeding a common signal to each of said antenna elements, said feeding means comprising phase shifting means for shifting the phase of said common signal with respect to each of said antenna elements; and

wherein said first and second antenna elements further comprise quadrifilar helical antennas, each antenna having four orthogonal conductive elements helically wound around said common axis.

2. An antenna system according to claim 1 wherein said feeding means includes coupler elements for exciting said orthogonal conductive elements of each said quadrifilar helical antenna in phase quadrature.

3. An antenna system comprising:

a plurality of antenna structures which include at least one antenna element having at least one conductive element helically wound in a first direction around a common axis, said antenna structures being arrayed axially spaced from one another along said common axis;

feeding means for feeding a common signal to each of said antenna elements, said feeding means comprising phase shifting means for shifting the phase of said common signal with respect to each of said antenna elements; and

wherein said antenna elements are quadrifilar helical antennas having four orthogonal conductive elements helically wound around said common axis.

4. An antenna system according to claim 3 wherein said feeding means includes coupler elements for exciting said orthogonal conductive elements of said quadrifilar helical antenna elements in phase quadrature.

5. An antenna system comprising:

a plurality of antenna structures which include at least one antenna element having at least one conductive element helically wound in a first direction around a common axis, said antenna structures being arrayed axially spaced from one another along said common axis;

feeding means for feeding a common signal to each of said antenna elements, said feeding means comprising phase shifting means for shifting the phase of said common signal with respect to each of said antenna elements;

at least one independent, helical antenna element disposed along said common axis between said antenna structures;

wherein said independent, helical antenna element further comprises at least one antenna structure having both a right-handed helical element and a left-handed helical element and wherein said left-handed antenna element and said right-handed antenna element are quadrifilar helices having four helically wound conductive elements.

6. A self-deploying axial antenna system having multiple independent antennas comprising:

a first antenna comprising a plurality of antenna elements, each having at least one conductive element helically wound around a common axis, said antenna elements being arrayed axially spaced from one another along said common axis;

first feeding means for feeding a common signal to each of said antenna elements wherein said feeding means comprises a phase shifting means for shifting the phase of said common signal with respect to each of said elements;

a second antenna disposed along said common axis between said antenna elements of said first antenna;

second feeding means for feeding a signal to said second antenna; and

a foldable boom structure for mounting said first and second antennas, said boom structure having at least one hinge for folding said boom structure for stowage.

7. An antenna system comprising:

a plurality of antenna structures comprising at least one quadrifilar helical antenna element having four orthogonal conductors helically wound around a common axis, said antenna structures being arrayed axially spaced from one another along said common axis; and

feeding means for feeding a common signal to at least one antenna element of each said antenna structure, said feeding means comprising phase shifting means for shifting the phase of said common signal with respect to said antenna elements;

wherein said antenna structures further comprise a first and second antenna element, said first antenna element having four orthogonal conductors wound in a left-hand direction, and said second antenna element having four orthogonal conductors wound in a right-hand direction.

8. An antenna system comprising:

a plurality of antenna structures comprising at least one quadrifilar helical antenna element having four orthogonal conductors helically wound around a common axis, said antenna structures being arrayed axially spaced from one another along said common axis;

feeding means for feeding a common signal to at least one antenna element of each said antenna structure, said feeding means comprising phase shifting means for shifting the phase of said common signal with respect to said antenna elements; and

at least one independent antenna element disposed along said common axis between said antenna structures, said independent antenna element further comprises both a right-handed helical conductor and a left-handed helical conductor.

9. An antenna system according to claim 8 wherein said left-handed helical conductor and said right-handed helical conductor comprise quadrifilar helices having four helically wound conductors.

10. An antenna system comprising:

a first antenna array including a plurality of helical antenna elements disposed along a common axis spaced axially from one another along said common axis;

a second antenna array comprising one or more helical antenna elements sharing said common axis of said first antenna array;

first feeding means for feeding a common signal to each of the antenna elements of said first antenna array, said feeding means comprising phase shifting means for shifting the phase of said common signal with respect to each of said antenna elements of said first antenna array;

second feeding means for feeding a second signal to each of the antenna elements of said second antenna array;

wherein each helical antenna element of said first antenna array comprises a first helical conductive element wound in a left-hand direction and a second helical conductive element wound in a right-hand direction, and said first and second helical conductive elements comprise quadrifilar helical antennas having four orthogonal conductive elements helically wound around said common axis.