In high-speed interconnect applications, the stability of signals directly affects equipment performance. Camera modules, display modules, 5G devices, and various high-speed transmission systems impose strict requirements on high-speed data links. However, in actual application environments, high-frequency signals are prone to various interferences, leading to data errors, image distortion, and even system anomalies. Micro coaxial cable harnesses (Micro Coaxial Cable Harness) are widely used in high-speed transmission due to their compact structure and excellent electrical performance. This article will combine common application scenarios to analyze the possible types of interference in micro coaxial cable harnesses and effective countermeasures.
One, crosstalk issues
Crosstalk is one of the most common types of interference in very thin coaxial cable bundles. When the electromagnetic field coupling between the internal or adjacent cable bundles is too strong, the signal of one channel may "leak" into another channel. In high-speed multi-channel applications, excessive crosstalk can lead to a decrease in signal integrity, thereby affecting the transmission speed and system stability.
Effective measures: Rational planning of cable arrangement, maintaining impedance consistency, and enhancing the integrity of the shielding layer are effective methods to reduce crosstalk.
Two, Electromagnetic Interference (EMI) and Radio Frequency Interference (RFI)
Extremely thin coaxial cable bundles can operate at high speeds, with working frequency bands reaching hundreds of MHz even several GHz. Under these conditions, external electromagnetic radiation or radio frequency signals are prone to interfere with the signal chain, increasing the error rate.
Measures for Solution: By optimizing the shielding structure, such as increasing the density of the weaving layer or using foil composite shielding, and ensuring the shielding transition at the connector port is complete, it can effectively reduce the impact of EMI/RFI on the system.
Third, reflection interference caused by impedance mismatch.
Impedance mismatch can cause reflections at discontinuities in interfaces or cables, superimposed on the original signal, leading to eye diagram closure and signal distortion.
Solution measures: Strictly control the characteristic impedance of extremely fine coaxial cable束（commonly 50Ω or 100Ω differential）to maintain the impedance continuity of the entire link, thereby reducing reflection interference.
Four, common-mode interference caused by poor grounding and shielding
In portable devices or small modules, due to space constraints, inadequate grounding design or insufficient grounding of the shielding layer, common-mode interference may occur, resulting in a decrease in the overall anti-interference ability of the system and making it more susceptible to external noise.
Optimization measures: Optimize the grounding path, ensure that the shielding layer is grounded with low impedance, and use common-mode chokes to improve the overall anti-interference performance when necessary.
Extremely fine coaxial cable bundles have significant advantages in high-speed signal transmission, but their high-frequency characteristics and compact structure are also prone to interference from crosstalk, EMI/RFI, impedance mismatch, and poor grounding. Engineers need to combine cable parameters, impedance control, shielding layout, and system-level electromagnetic compatibility design when designing and selecting to achieve stable and reliable high-speed signal transmission. Through scientific design and reasonable protection, micro coax not only ensures the integrity of the high-speed signal path but also meets the comprehensive requirements of modern electronic devices for slimming, high performance, and anti-interference capabilities.
I amSuzhou Huichengyuan Electronic TechnologyLong-term focus on the design and customization of high-speed signal cables and ultra-fine coaxial cables, committed to providing stable and reliable high-speed interconnect solutions. For more information or customization needs, please contact:Manager Yin 18913280527 (WeChat same number)。
