In the modern era of information, various devices rely on data transmission cables to send files at high speeds, for example, data, image, audio, and video transmissions. It’s become normal for modern people to have multiple transmission cables.

A simple transmission cable is built out of a variety of different components. The processing, compatibility, and high-frequency characteristics between the various components can cause major issues for cable manufacturers. The first issue that must be dealt with is controlling the characteristic impedance within a time domain. The cable is like a pipe during signal transmission, which must be kept unblocked.

What are the Potential Issues?

Characteristic impedance directly affects the integrity of the signals. It could be called the mother of high frequencies since poor design and processing can be seen in the characteristic impedance. Below is a list of some related common issues.

  • The contact area of the terminals is too small, resulting in excessive signal reflection
  • Uneven coverage of bare wires can cause signal distortion
  • Poor cable routing and bending can affect signal dispersion
  • Weak soldering and open circuits can cause signal transmission failure

Poor design can affect the product’s high-frequency characteristics, such as insertion loss, return loss, or NEXT/FEXT crosstalk. When the propagation delay or delay skew exceeds the capability of the original chip, the bit error rate will increase, resulting in the data requiring to be retransmitted. This can lead to slower transmission speeds or even transmission failure. If a manufacturer runs into this issue and lacks problem analysis experience, orders could be lost and production could be delayed, leading to customer complaints or even worse consequences.

Allion Has Decades of Experience! Here Are Some Examples.

Allion has decades of experience with characteristic impedance analysis for transmission cables and connectors. With our analysis process, most potential issues can be eliminated. Our team further assists clients with planning and designing improvements to their products. In one of our past cases, we found that the insertion loss of the product was too high, easily causing data transmission failure during usage. After testing and analyzing the characteristic impedance of our sample product, our team found that the impedance of the paddle card was too low and the cable was stripped too much. Both of these issues resulted in a gap, affecting the signal transmission process.

Fig.1 shows the waveform of the cable before adjusting the impedance. It can be seen that the area marked in red has a difference of 21.42Ω. This results in affecting the insertion loss (Fig. 2) to exceed the standard level, causing a large amount of signal loss.

After our consulting team analyzed the situation and provided the client with suggestions such as paddle card impedance correction and bare wire processing, the impedance gap improved to 12.29Ω (Fig. 3). The insertion loss levels were controlled within the standard and immediately improved the quality of the product (Fig. 4).

Allion can provide a faster, easier and better integrated consulting services and solutions. Below are the advantages of partnering with us.


Allion has decades of experience with high-frequency testing and consulting. With services like testing, analysis, R&D, and various teams, Allion can quickly respond to client needs, understand issues, obtain accurate test results, and prescribe appropriate solutions.


Allion has a collection of oscilloscopes and network analyzers of different brands, ensuring communication with clients. Any issues caused by poor characteristic impedance can be easily solved by us.


Allion has the most complete testing equipment for high-frequency products in the industry. In addition to providing consulting services to clients and helping them understand specifications and testing methods, we also assist clients with extreme scenario testing to ensure product performance in harsh environments. Allion aims to improve all our clients’ brand value and customer loyalty.


If you have any further needs for testing, verification, or consulting services related to the cable and connector, please feel free to contact with us.