RELEASE MECHANISM FOR THE ANTENNA UNIT OF HELICOPTER DATA TRANSMISSION EQUIPMENT

Abstract

The invention relates to antenna-feeder devices for aeronautical radio communications. The technical result consists in eliminating parasitic feeder radiation. The device is intended for use with the Mi-8 helicopter. The proposed device comprises: a release mechanism, the movable link of which is formed by a rigid tube made of aircraft-grade aluminum (1), forming the outer conductor of a coaxial path, wherein a central conductor with insulation is routed within the tube, and a radiating element (3) is secured to the end of the tube through a transition flange (2).

Description

[0001] Technical field

[0002] The utility model relates to the field of aviation radio communications, namely to antenna-feeder devices of aircraft, and is intended for placing the antenna of data transmission equipment on the lower part of the fuselage of a helicopter, primarily of the Mi-8 type.

[0003] Technology Level

[0004] The Raduga-2K data transmission equipment, installed on Mi-8 and Ka-226 helicopters, is well-known. Its antenna is attached to the rear landing gear via a special release mechanism. This mechanism is structurally complex, has poor repairability, and requires significant labor for maintenance. Furthermore, a drawback of this known solution is its limited data transmission range (specified at 30 km), which is due to the antenna's suboptimal radiation pattern due to the influence of the landing gear's metal structure and parasitic radiation from the feeder. The closest analogue (prototype) is the MP-100 antenna release mechanism (Supplement to the operational documentation of the Mi-8MTV-2 helicopter 477.0000.00.ED.D-71 b) for R-173 radio stations, in which the movable link is made in the form of a telescopic rod with a standard antenna.The disadvantage of the prototypes is the presence of parasitic radiation on the outer surface of the feeder and the influence of the helicopter design elements on the radiation pattern.

[0005] Disclosure of Utility Model

[0006] The objective of the proposed utility model is to simplify the design, improve maintainability and increase the data transmission range.

[0007] The technical result consists in eliminating parasitic signal reflection from the helicopter's structural elements.

[0008] The specified technical result is achieved by the fact that in the antenna unit, comprising an antenna with a radiating element, a coaxial cable and a release mechanism with a movable link, the movable link is made rotatable relative to the mechanism housing and is a rigid conductive tube (1), forming the outer conductor of the coaxial path in the section from the release mechanism housing to the radiating element. A coaxial cable passes inside the tube, wherein its outer conductor (braid) is galvanically connected to the inner surface of the tube, which eliminates parasitic radiation of the feeder. At the output end of the tube, the radiating element is fixed through a transition flange (2), the central core of the cable is connected to the antenna pin through the flange insulator, and the braid is connected through the tube and flange to the housing of the radiating element.The extension length of the radiating element from the axis of rotation is at least 40 cm, which ensures that the antenna is located outside the zone of shading and intense electromagnetic reflections from the massive metal structures of the fuselage and landing gear of the Mi-8 helicopter in the operating position.

[0009] In the preferred embodiment, the MP-100 mechanism is used as the release mechanism, the standard antenna of which is replaced by the specified tube with a central conductor and an adapter flange.

[0010] Brief description of drawings

[0011] Fig. 1 shows a general view of the Mi-8 helicopter, indicating the location of the mechanism installation on the lower part of the fuselage.

[0012] Fig. 2 shows an enlarged view of the antenna mounting unit to the adapter flange.

[0013] Implementation of a utility model

[0014] The proposed extension mechanism is based on the standard MP-100 antenna extension mechanism, which is attached to the bottom of the helicopter fuselage. The extension mechanism's moving link is designed as a rigid metal tube (1), which serves as the outer conductor of the coaxial line. The coaxial cable is routed inside the tube. This design eliminates parasitic radiation along the entire length of the extension link, as well as parasitic reflections from helicopter structural elements, thereby stabilizing the antenna's radiation pattern.

[0015] A radiating element is secured to the output end of the tube via a transition flange (2). The transition flange provides mechanical transition and galvanic contact between the cable's outer braid and the radiating element's body through the tube material. The cable's central core is connected to the pin portion of the radiating element via the flange insulator.

[0016] The operating principle is as follows. When a command is given, the release mechanism rotates the tube with the cable and the antenna attached to the flange from the transport position (pressed against the fuselage) to the operating position (extended). In the operating position, for example, with an extension length of 40 cm from the axis of rotation, the radiating element is located outside the shadow zone and intense electromagnetic reflections from the massive metal structures of the fuselage and the helicopter's landing gear. These factors combined ensure an increase in the range of stable data transmission from 30 to 43 km (this value was obtained empirically).

Claims

1. A release mechanism for an antenna unit of a helicopter data transmission equipment, comprising a pin antenna with a radiating element, a coaxial cable and a release mechanism with a movable link, characterized in that the movable link of the release mechanism is made in the form of a rigid conductive tube that forms the outer conductor of the coaxial path in the section from the housing of the release mechanism to the radiating element, wherein a central conductor with dielectric insulation is laid inside said tube, and a coaxial feeder is connected to the tube in the area of ​​the housing of the release mechanism, a radiating element is secured to the output end of the tube by means of a transition flange, electrically connected to the central conductor, wherein the extension length of the radiating element from the axis of rotation is selected from the condition of locating the radiating element outside the zone of parasitic reflections from the structural elements of the helicopter.

2. A release mechanism for an antenna unit according to paragraph 1, characterized in that the release mechanism is designed to ensure that the extension length of the radiating element from the axis of rotation is at least 40 cm.

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