Antenna assembly for aircraft

Abstract

An antenna assembly for aircraft including: a vertical tail of the aircraft including a front spar, a leading edge skin covering a leading portion of the front spar and a rib extended between the front spar and the leading edge skin; an antenna radiating element extending a length of the vertical tail and positioned between the leading edge skin and the front spar; a first metallic element included with or attached to the front spar; a second metallic element, wherein the second metallical element is electrically coupled to the antenna radiating element and to the first metallic element; an antenna coupler in electrical electrically connected to the antenna radiating element and the first metallic element, and wherein a closed looped electrical circuit is formed by the antenna radiating element, the first metallic element, the second metallic element and the antenna coupler.

Claims

1. An antenna assembly for aircraft comprising: an antenna radiating element; an antenna coupler in electrical contact with the antenna radiating element; a portion of a vertical tail of the aircraft, wherein the portion of the vertical tail includes a portion of a front spar; a first metallic element in electrical contact with the antenna coupler, wherein the first metallic element comprises said portion of the front spar, a second metallic element in electrical contact with the antenna radiating element and with the first metallic element, whereby the antenna radiating element is parallel to the portion of the front spar, and wherein the first and the second metallic elements and the antenna coupler are configured as an electrical circuit which in use is a closed loop current path flowing through said circuit.

2. The antenna assembly, according to claim 1 wherein the portion of the vertical tail includes a leading edge rib in contact with the front spar such that the second metallic element comprises said leading edge rib.

3. The antenna assembly, according to claim 2 wherein the antenna radiating element and the leading edge rib are in direct contact.

4. The antenna assembly, according to claim 1 wherein the first metallic element also comprises a metallic plate, wherein the metallic plate includes an attachment to the portion of the front spar.

5. The antenna assembly, according to claim 4 wherein the second metallic element comprises a metallic support mast extending between the antenna radiating element and the metallic plate.

6. The antenna assembly, according to claim 4 wherein the metallic plate comprises a grounded metallic attachment at a front end of the metallic plate, and the grounded metallic attachment is configured to be joined to the fuselage of the aircraft.

7. The antenna assembly, according to claim 6, wherein the grounded metallic plate extends to and contacts with the antenna coupler such that an electrical connection is formed between the metallic plate and the coupler.

8. The antenna assembly, according to claim 4 which further comprises at least a dielectric support mast extending between the antenna radiating element and the metallic plate.

9. The antenna assembly, according to claim 1 further comprising a portion of a fuselage whereby the fuselage is metallic and the antenna coupler is attached to the fuselage and the antenna coupler is also in electrical contact with the fuselage and the first metallic element is in electrical contact with the fuselage.

10. The antenna assembly, according to claim 1, further comprising an element configured to transmit electric current flowing between the first metallic element and the antenna coupler.

11. An antenna assembly for aircraft comprising: a vertical tail of the aircraft including a front spar, a leading edge skin covering the front spar, and a rib extending between the front spar and the leading edge skin; an antenna radiating element extending a length of the vertical tail and positioned between the leading edge skin and the front spar; a first metallic element included with or attached to the front spar; a second metallic element, wherein the second metallic element is electrically connected to the antenna radiating element and to the first metallic element; an antenna coupler is electrically connected to the antenna radiating element and the first metallic element, and wherein a closed looped electrical circuit is formed by the antenna radiating element, the first metallic element, the second metallic element and the antenna coupler.

12. The antenna assembly of claim 11 wherein the antenna radiating element is a metallic beam having a first end attached to the antenna coupler and an opposite end attached to the second metallic element.

13. The antenna assembly of claim 11 wherein the second metallic element is a metallic support mast extending between the antenna radiating element and the front spar.

14. The antenna assembly of claim 11 wherein the antenna radiating element is parallel to the first metallic element.

15. The antenna assembly of claim 11 wherein metal forming the front spar comprises the first metallic element, and metal forming the rib comprises the second metallic element.

16. The antenna assembly of claim 11 further comprising a dielectric support mast extending between the front spar and the antenna radiating element.

17. The antenna assembly of claim 11 further comprising a grounded metallic plate attached to the second metallic element and a fuselage of the aircraft, wherein the closed loop includes the grounded metallic plate.

18. The antenna assembly of claim 17 wherein the closed loop includes a metallic portion of the fuselage.

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1a is a schematic view of an embodiment having a non-metallic fuselage wherein the closed loop is created by the connection of the antenna coupler, the antenna radiating element, the first and the second metallic elements and an electrical connection between the first metallic element and the coupler.

(2) FIG. 1b is a schematic view of an embodiment having a metallic fuselage wherein the closed loop is created by the connection of the antenna coupler, the antenna radiating element, the first and second metallic elements and the fuselage.

(3) FIG. 2 is a schematic perspective view of a first embodiment of the invention showing for the sake of clarity only the front spar and a leading edge rib of a vertical tail plane and an antenna radiating element.

(4) FIG. 3 is a schematic perspective view of a second embodiment of the invention showing a rear part of an aircraft and the antenna assembly.

(5) FIG. 4 is a schematic perspective view of the second embodiment of the invention showing the front spar and the antenna assembly.

(6) FIG. 5 is a schematic perspective view of the second embodiment of the invention.

(7) FIG. 6 is a schematic perspective view of the rear part of the embodiment shown in FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

(8) As described in the figures the antenna assembly comprises the antenna radiating element (10) and a portion of the front spar (2) of the vertical tail plane (1), which is the first metallic element (2, 12) of the antenna assembly. It also comprises a second metallic element (3, 14) located in electrical contact with the antenna radiating element (10) and with the first metallic element. FIGS. 1, 2, 3 and 4 show the antenna radiating element (10) parallel to the portion of the front spar (2).

(9) FIGS. 1a and 1b show a schematic view of the closed loop created by the connection of the elements of the antenna assembly. The antenna coupler (11) is electrically connected to the antenna radiating element (10) which is in electrical contact with the second metallic element which is also in electrical contact with the first metallic element which is also in electrical contact with the antenna coupler (11) by means of the fuselage (20) or by means of an element (40) able to transmit the electric current both extending between the first metallic element and the coupler (11). The current path is shown in the figures by the arrows.

(10) FIG. 1a shows an embodiment in which the fuselage (20) is non-metallic, therefore unable to transmit an electrical current. In this embodiment for performing an electrical circuit in which a closed loop is described, the first metallic element and the coupler (11) are to be connected by an element (40) able to transmit the electric current, for instance, a cable, a metallic element, etc, Therefore, the antenna assembly further comprises said element (40) able to transmit the electric current that extends between the first metallic element and the antenna coupler (11).

(11) FIG. 1b shows an embodiment in which the fuselage (20) is metallic. As shown in FIGS. 1a, 1b, 2, 3 and 4 the first metallic element is connected to the fuselage (20) of the aircraft and FIGS. 1a, 1b, 3 and 4 show the antenna coupler (11) also connected to the fuselage (20), therefore as the antenna assembly is configured as an electrical circuit, the current flows through the portion of the metallic fuselage (20) extending between the joint with the first metallic element and with the antenna coupler (11). Therefore the antenna assembly further comprises said portion of the fuselage (20) extending between the joint with the first metallic element and with the antenna coupler (11).

(12) FIG. 2 shows a first embodiment of the invention. This first embodiment may be used in aircrafts which have an internal metallic structure so that the front spar (2) and the leading edge ribs (3) are metallic. In this first embodiment the second metallic element comprises said leading edge rib (3). In addition the antenna radiating element (10) and the leading edge rib (3) are in direct contact. The fuselage (20) is also metallic.

(13) The antenna coupler (11) is electrically connected to the antenna radiating element (10) and also attached to the fuselage (20) so that the antenna radiating element (10), the leading edge rib (3), the front spar (2), the antenna coupler (11) and the portion of the fuselage (20) extending between the connection with the front spar (2) and the antenna coupler (11) are configured as an electrical circuit in which a closed loop is described by the current path.

(14) FIG. 3 shows a perspective view of a second embodiment of the invention, clearly showing that the antenna assembly is integrated into the internal supporting structure, more specifically being arranged as a part of or attached to the front spar (2).

(15) FIG. 4 is an expanded view of FIG. 3, showing the antenna radiating element (10) and the front spar (2). In this embodiment the first metallic element also comprises a metallic plate (12), which comprises metallic attaching means (13) to the front spar (2), as shown in FIG. 6. A metallic plate with U shape or grounded metallic plate (15) allows the mechanical and electrical connection of the metallic plate (12) to fuselage (20) which is also metallic and so reproducing the aforementioned closed loop also in this embodiment.

(16) For a non-metallic fuselage (20), ie, for a fuselage (20) made of composite, the grounded metallic plate (15) can be extended until it contacts the antenna coupler (11) such that the electrical connection between the metallic plate (12) and the coupler (11) is made.

(17) It further comprises at least a metallic support mast (14) extending between the antenna radiating element (10) and the metallic plate (12) as a second metallic element. This second embodiment may be used in aircrafts, which have an internal structure made of composite materials, where the front spar (2) and the leading edge ribs (3) are made of composite material. In this second embodiment the first metallic element comprises the front spar (2), which is made of composite and the metallic plate (12), which are directly attached together.

(18) The antenna coupler (11) is operatively connected to the antenna radiating element (10) so that the antenna radiating element (10), the support mast (14) and the metallic plate (12) attached to the front spar (2) are configured as a circuit in which a closed loop is described by the current path. As previously explained, if the fuselage (20) is metallic the current flows through it (20) as the metallic plate (12) is electrically connected with the fuselage (20) by means of the grounded metallic plate (15) and the antenna coupler (11) is also electrically connected to the fuselage (20). If the fuselage (20) is non-metallic an electrical connection between the metallic plate (20) and the antenna coupler (11) has to be provided.

(19) It may further comprises at least a dielectric support mast (16) extending between the antenna radiating element (10) and the metallic plate (12).

(20) The antenna metallic plate (12) is electrically connected to the aircraft structure through the metallic attachments means (13) in contact with the front spar (2) of the VTP (1) and to the fuselage (20) through a specific grounded metallic attachment (15) designed to interconnect this element with the fuselage (20). This design provides good electrical continuity between the metallic plate (12) and fuselage (20), ensuring a low DC impedance path for the radio frequency return current towards the antenna coupler (11) which is also grounded to the fuselage (20), this being a critical feature for proper HF system efficiency.

(21) FIG. 4 also shows a dielectric rib (4), which is used to support a dorsal fin in order not to disturb the antenna radiation pattern.

(22) The antenna radiating element (10) is coupled by one or more feed lines (30) to the HF radio coupler or couplers (11). To increase system efficiency, it is necessary to locate the antenna couplers (11) adjacent to the antenna radiating element (10) to reduce losses and ensure proper antenna coupling. Two feed line attachments could be used, one for couplers (11) with coaxial output using a metallic plate and other for couplers (11) with screwed output using straps.

(23) FIGS. 1, 2, 3 and 4 show the portion of the front spar (2) connected to the fuselage (20) of the aircraft and FIGS. 1, 3 and 4 show the antenna coupler attached to the fuselage (20).

(24) The whole antenna would be covered by a dielectric dorsal fin being protected from impacts or weather damage and to avoid adding additional aerodynamic drag to the aircraft and, at the same time, not disturbing the antenna radiation. An access door in the dorsal fin allows mounting and dismounting the antenna couplers (11) and the maintenance operations.

(25) The antenna metallic radiating element is normally about 0.1 m wide and 1.3 m long, the antenna metallic plate has typically a width double that of the radiating element and a length equal or slightly greater. The distance between the radiating element and the metallic plate shall be enough to have an open area of about 0.5 square meters.

(26) The antenna object of the claimed invention is designed for long range communications in the high frequency band (2 MHz to 30 MHz).