CN109494478B

CN109494478B - SMA connects suitable for conformal antenna house

Info

Publication number: CN109494478B
Application number: CN201810770408.5A
Authority: CN
Inventors: 司源; 房亮; 蒋小杰
Original assignee: AVIC Research Institute Special Structures Aeronautical Composites
Current assignee: AVIC Research Institute Special Structures Aeronautical Composites
Priority date: 2018-07-13
Filing date: 2018-07-13
Publication date: 2021-03-26
Anticipated expiration: 2038-07-13
Also published as: CN109494478A

Abstract

The invention belongs to the field of aerial radar antenna covers, and particularly relates to an SMA connector suitable for a conformal antenna cover. The SMA connector mainly comprises a feed pin, an auxiliary fixing pin, a supporting lug, a stud, a cushion block and a nut. The working frequency band is not more than 6GHz, and the antenna is suitable for feeding of conformal antenna housing metal patches and grounding of metal floors. Aiming at the use environment, the curved surface appearance and the special structure of the conformal radome, the SMA connector provided by the invention can effectively improve the reliability of the welding points of the pins and the metal patches, and is in shape fit with the metal floor, so that good conduction is ensured, and the technical requirements of feeding and grounding of the conformal radome are better met.

Description

SMA connects suitable for conformal antenna house

Technical Field

The invention belongs to the field of aerial radar antenna covers, and particularly relates to an SMA connector suitable for a conformal antenna cover.

Background

The development trend of new concept weapon platforms is intellectualization, unmanned, stealth and biochemical simulation. This presents a significant challenge to radar antenna systems, requiring not only a higher level of integration of the functional and physical architecture of future radar antenna systems, but also a better integration of the radar antenna systems into the weapons platform. The traditional radar antenna is directly installed on the surface of a weapon platform (an airplane, a guided missile, a ship, a satellite and the like), or a radar antenna cover is required to be independently installed for protection, so that the pneumatic/stealth performance of the weapon platform can be influenced. The additional antenna support structure and auxiliary equipment results in a significant increase in the internal footprint, weight, complexity, and manufacturing and maintenance costs of the weapons platform. Therefore, the traditional structure form that the antenna and the antenna housing are mutually independent is difficult to adapt to the operation mode and the functional requirement of a new generation weapon platform, and the conformal antenna housing is produced at the same time and becomes one of the key directions of the development of a new concept weapon platform.

The general structural form of the conformal radome is as follows: the method is characterized in that a low-dielectric low-loss composite material is adopted to manufacture a multilayer bearing structure conformal with the surface of a weapon platform, and a large number of metal patches, TR circuits, feed networks, thermal control devices and the like which are in different shapes or periodically arranged are embedded among layers in the forming and manufacturing stage of the multilayer composite material structure, so that a multilayer conformal array structure with a complex structure is formed. The conformal antenna housing has the obvious structural function integration characteristic, is organic comprehensive application of the traditional antenna and antenna housing technology, and can well improve the performances of the weapon platform in various aspects such as pneumatics, stealth, information perception and processing, weight, use and maintenance and the like.

Conformal antenna house compares with traditional radome, except having mechanical interface, still should have the interface with external signal system to satisfy power supply and signal transmission's demand. The interface between the conformal radome and an external signal system is realized by a specific metal patch layer and a signal wire or an SMA joint in a welding mode. When a signal wire welding mode is adopted, one end of a signal wire is welded with the designated position of the metal patch layer, and the other end of the signal wire is led out to the outside of the conformal antenna housing. In engineering practice, SMA joints are more commonly used. The SMA connector mainly comprises a shell, a lug, a stitch and the like, wherein the end part of the shell is provided with a thread and can be in threaded connection with an external signal system. The SMA is usually made of copper alloy with good conductivity, and the inside of the SMA is filled with an insulating material. When the SMA connector is installed, through holes need to be manufactured on the metal patch, the dielectric layer and the metal floor, the stitch is welded with the designated position of the metal patch layer, the lug of the SMA connector is grounded and conducted with the metal floor, and the SMA connector is usually welded or screwed through the through hole on the lug. The conventional SMA connector is used for a conventional planar circuit board, which cannot completely meet the technical requirements of a conformal radome, and has the following problems.

Firstly, the use environment of the conformal radome is more severe than that of the traditional planar circuit board, the conformal radome is required to bear loads in various forms such as pneumatics, vibration, impact, heat and the like, the stress/strain inside the structure is large, the phenomenon of insufficient connection strength is easy to occur in a single stitch welding mode of a conventional SMA connector, and the welding point is likely to break and fail.

Second, the conformal radome body structure is typically a non-metallic composite sandwich structure. Metal flooring is typically constructed by applying a copper-clad film (about 18 μm thick) to a relatively thin composite skin (typically no more than 1mm thick). When the SMA connects and the metal floor are conducted, no matter the lug is welded or the through hole on the lug is screwed, some difficulties exist: the metal layer is easy to be damaged by welding in a welding mode, and the quality of a welding spot is poor; and the adoption of a screw connection mode is not beneficial to grounding conduction because the skin is thin and the connection reliability is difficult to ensure.

In addition, the conformal radome is generally in a curved surface shape, and the SMA joint designed for the planar circuit board needs to be optimized and improved in shape. Especially, the lug of the conventional SMA joint cannot be completely fitted with the metal floor of the conformal radome with a curved surface appearance, which is not beneficial to connection and grounding conduction.

Disclosure of Invention

The invention relates to an SMA connector, which has a working frequency band not greater than 6GHz and is suitable for feeding of conformal radome metal patches and grounding of metal floors. Aiming at the use environment, the curved surface appearance and the special structure of the conformal radome, the SMA connector provided by the invention can effectively improve the reliability of the welding points of the pins and the metal patches, and is in shape fit with the metal floor, so that good conduction is ensured, and the technical requirements of feeding and grounding of the conformal radome are better met.

Technical scheme

An SMA connector suitable for a conformal radome is mainly composed of three parts. In the joint main body, 1 is a feed pin, 2 is an auxiliary fixing pin, 3 is a supporting lug and 4 is a stud. Besides the joint main body, the joint also comprises a 5-cushion block and a 6-nut.

The feed pin 1 is welded with a welding disc of the conformal radome radiation patch. The auxiliary fixing pins 2 are distributed on the supporting lug 3 and can be used for being welded with the medium layer, and isolated bonding pads are arranged on the surface of the medium layer. The cushion block 5 can be sleeved in the stud 4, and the curved surface part of the outer surface of the stud can be in shape with the local curved surface of the conformal radome for installing the SMA connector. The internal thread of the nut 6 is matched with the external thread of the stud 4, and the cushion block 5 can be pressed after being screwed in.

All parts of the SMA joint are made of copper alloy. The surfaces of the stud 4, the cushion block 5 and the nut 6 are plated with gold.

The thickness of the supporting lug 3 is 1 mm-1.5 mm. When the SMA connector is installed, the antenna can be properly bent and attached according to the curved surface shape of the conformal antenna housing.

The shape of the supporting lug 3 is specifically designed according to the shape of the radiation patch and the position of the pad.

Technical effects

The SMA connector of the invention has, in addition to the conventional feed pin 1, a plurality of auxiliary fixing pins 2 and support tabs 3. The multipoint welding can dispersedly bear external load, the lug can enhance the local structural rigidity of a welding position, further the connection strength of the SMA connector and the conformal antenna housing is enhanced, the connection stress/strain of a feed welding spot is reduced, and the reliability of feed is improved. The grounding conduction of the SMA connector and the metal floor of the conformal radome adopts a joint crimping mode, and is mainly realized through a cushion block 5 and a nut 6 as shown in figure 2. After the cushion block 5 is sleeved into the stud 4, the nut 6 is screwed, so that the curved surface part of the cushion block 5 can be tightly attached to the curved surface of the conformal radome metal floor, good conductive contact can be ensured, the reliability is high, and the operation is simple.

Drawings

FIG. 1 is an exploded view of an SMA connector suitable for use with a conformal radome

FIG. 2 is a diagram of an SMA connector mounting form suitable for use with a conformal radome

Wherein, the feed device comprises 1-feed pin, 2-auxiliary fixing pin, 3-supporting lug, 4-stud, 5-cushion block and 6-nut.

Detailed Description

1) A metal patch is arranged on a specific dielectric layer of the conformal radome, and feeding is needed. According to the requirement of the feeding position of the metal patch, a through hole is formed in the designated position of the dielectric layer, and a feeding pin 1 and an auxiliary fixing pin 2 of the SMA connector are respectively welded with the metal patch and the bonding pad. When welding, the supporting lug 3 is tightly attached to the other side of the medium layer and can be properly bent to be in a shape if necessary.

2) And integrally forming the medium layer welded with the SMA connector and other functional layers of the conformal radome. Through holes are manufactured on the conformal radome dielectric layer and the metal floor, so that the studs 4 are exposed.

3) And sleeving the cushion block 5 into the stud 4, and properly adjusting to ensure that the cushion block 5 is in a shape corresponding to the surface and is jointed with the conformal radome metal floor.

4) And screwing the nut 6 tightly to press the cushion block 5, so that the conformal surface of the cushion block 5 is tightly attached to the conformal radome metal floor.

Fig. 1 is an exploded view of an SMA joint of the invention, and fig. 2 is an installation form. The SMA connector is mainly composed of three parts. In the joint main body, 1 is a feed pin, 2 is an auxiliary fixing pin, 3 is a supporting lug and 4 is a stud. Besides the joint main body, the joint also comprises a 5-cushion block and a 6-nut.

Claims

1. The utility model provides a SMA connects suitable for conformal antenna house, SMA connects and comprises feed stitch (1), supplementary fixed stitch (2), support auricle (3), double-screw bolt (4), cushion (5) and nut (6), its characterized in that: the feed pins (1) are welded with bonding pads of a conformal radome radiation patch, a plurality of auxiliary fixing pins (2) are distributed on the support lug (3) and used for being welded with the dielectric layer, isolated bonding pads are arranged on the surface of the dielectric layer, the stud (4) is sleeved in the cushion block (5), and the curved surface part of the outer surface of the cushion block (5) is in shape fit with the local curved surface of the conformal radome provided with the SMA connector; the internal thread of the nut (6) is matched with the external thread of the stud (4) and screwed into the rear compression cushion block (5); the thickness of the supporting lug (3) is 1-1.5 mm, the appearance of the supporting lug (3) is determined according to the shape of the radiation patch and the position of the bonding pad, and the supporting lug is bent and attached according to the appearance of the curved surface of the conformal radome when the SMA connector is installed.

2. The SMA joint suitable for a conformal radome of claim 1, wherein: all parts of the SMA joint are made of copper alloy, and the surfaces of the stud (4), the cushion block (5) and the nut (6) are plated with gold.