RF cable for weight reduction of aerospace communication cable

RF coaxial cable refers to a cable with two concentric conductors, and the conductor and the shielding layer share the same axis. The term "coaxial" means that the inner conductor and outer shield share a geometric axis.

The world premiere of SMA coaxial cable assemblies in 1858 was used for the first and later trans-Atlantic cable assemblies. SMA coaxial cable was a transmission cable assembly used to transmit low-loss high-frequency electrical signals. It is suitable for applications such as telephone trunk lines, broadband Internet cables, high-speed computer data buses, cable television signals, and the connection of radio transceivers with their antennas. It is different from other shielded cables because the size of the cable and the connector are controlled to provide an accurate and constant conductor spacing, which is a necessary design form for it as a transmission line.

Radio frequency coaxial cables are widely used in high frequency communication systems, such as SMA coaxial cable assemblies, which have excellent high frequency transmission performance and power capacity, and have formed a certain scale and commercialization in the international and domestic markets. According to the market demand of high-end RF coaxial cable, such as PTFE insulated semi-rigid RF coaxial cable must meet MIL-C-17C (US military standard) or corresponding domestic coaxial requirements, and can be used for rockets, satellites, measurement and control equipment, and High-frequency connection lines in mobile instruments and communication equipment (usually characteristic impedance is 50Ω, operating environment temperature is between -55°C~+250°C, relative humidity can also meet the design of 93+2% 93-3%, etc.) Require).

At present, the outer insulating material in the radio frequency coaxial cable is another layer of ring conductor. The shielding layer outside the conductor of the SMA rf coaxial cable is usually made of metal copper or aluminum tube structure, and most of it is a braided structure. Although this shielding layer is shielded The effect is relatively high. With the continuous development of composite materials, composite materials with lightweight advantages have been widely used in military industry and information communication, so the lightweight requirements of equipment also apply to the weight of RF coaxial cables, because the metal itself is inevitable The weight and the burrs puncturing the shielding layer under repeated bending are not in line with the modern military and communications design concepts.

The working environment of electrical equipment and instrument wiring connections in modern aerospace, shipborne, and electronic fields is particularly harsh. In order to realize the rigorous design ideal of modern information and communication, it is necessary to replace traditional metal conductive shielding materials with non-metallic fiber filaments. As early as 2004, Europe and the United States have adopted non-metallic PBO fiber filaments to replace traditional metals. For example, a non-metallic fiber yarn that combines a non-metallic PBO fiber and a metal coating, compared with the traditional silver-plated copper wire, Lyofil@ fiber yarn has a weight reduction of up to 73%, and it also has the shielding performance of a metal material. The new generation of ultra-light radio frequency coaxial cables, such as SMA coaxial cable assemblies, need to have excellent weight reduction effects, and also have excellent properties such as metal mechanical and temperature phase stability, low attenuation, high shielding effect, flexibility, energy consumption, and light weight. All in one.

Since the emergence of large-scale demand in the RF coaxial cable market in my country in 2009, SMA coaxial cable assemblies have entered a stage of high-speed development in military electronics, aerospace, microwave communications, mobile communications, communication terminals and other industries. The demand for high-end radio frequency coaxial cables will continue to grow rapidly. At the same time, the requirements for the speed and quality of signal transmission will continue to increase in the future. At the same time, the demand for high-end RF coaxial cable anti-wave sleeves will be more Promising.