From material to technology: Unveiling the high-performance secrets of ultra-fine coaxial cables

In the context of the ever-increasing demand for high-speed and high-frequency signal transmission, micro coaxial cable, with its miniaturized structure, high flexibility, and excellent signal performance, has been widely used in various fields such as consumer electronics, medical equipment, 5G communication, and aerospace. This article will analyze its core technology and innovative directions from three aspects: structural design, signal control, and manufacturing process.

Part 1: Structure and Material Design
The ultra-fine coaxial cable is composed of a micro central conductor (usually a multi-strand copper绞 wire of 30～46 AWG) covered with an insulating layer, and the outer layer is protected by a metal braid or wrap shield layer plus a plastic sheath. This structure provides excellent electromagnetic shielding performance while also considering the thinness, flexibility, and toughness characteristics.
In higher requirement applications, to reduce dielectric loss and improve signal consistency, bubble PTFE and other low dielectric constant materials are often used as insulating media, so that high-frequency signals can still maintain stable transmission in complex environments.

Signal Integrity and Loss Control
The performance of ultra-fine coaxial cables is centered on strict control of signal loss. In engineering design, it is usually necessary to optimize insertion loss, return loss, and VSWR (Standing Wave Ratio) to ensure signal integrity and low reflection characteristics.
In addition, by using the "paddle card" structure (with PCB or FPC as the termination substrate), the signal path can be shortened and impedance matching can be strengthened, thereby significantly improving the high-frequency response and enhancing the overall transmission quality.

Chapter 3 Manufacturing and Joining Techniques
Due to the extremely thin diameter of the micro coaxial cable, any minor error can affect performance. Traditional mechanical stripping methods have problems with precision fluctuations and tool wear, and are not suitable for high-density wire harnesses.
Therefore, laser stripping technology has become the mainstream choice. It uses a non-contact processing method, utilizing CO₂ or pulsed laser to achieve high-precision coating stripping and shielding layer windowing. Not only is the precision high, but also the repeatability and reliability are excellent, providing an ideal prerequisite for subsequent terminal welding.

Four, application scenarios and innovation trends
Micro coaxial cable bundles have become an important carrier for high-density signal transmission in devices such as 5G, medical, industrial control, laptops, and smart terminals, playing a crucial role especially between modules such as motherboards, cameras, displays, and sensors.
As devices continue to become thinner and lighter, with higher resolutions and refresh rates, the requirements for ultra-thin coaxial cables in terms of signal integrity, impedance matching, and bending performance are also increasingly stringent.
Future development trends mainly include:
High-density multi-core design: Meets the high-speed interconnection requirements of complex circuit modules.
Flexibility and micro-bend optimization: improve the flexibility and reliability of wiring in confined spaces.
Material customization and insulation improvement: reduce transmission loss, enhance anti-interference performance.

The competitiveness of ultra-fine coaxial cables comes from the integration of material optimization, microstructure design, and high-precision processing. Their continuous breakthroughs in impedance control, shielding efficiency, welding technology, and flexible design make them an indispensable key component in modern high-frequency interconnect systems.
I am[Suzhou Huichengyuan Electronic]Deeply engaged in the field of high-speed signal cable harnesses and ultra-fine coaxial cable harnesses, focusing on providing customized solutions with high reliability and high-speed transmission. If you have any related needs or would like to learn more, please feel free to contact:Manager Zhang 18913228573 (WeChat same number)。