Quadrax is a 4 channel differential connector suitable for high speed electrical network applications. According to its data sheet, this Souriau-Corporation manufactured quadrax contact has excellent network performances, minimum crosstalk, and perfect matching. It is designed to operate in harsh environments and handle a high density of links. Here we show how to simulate an Ethernet 100 Mbps quadrax contact using HFWorks in an S-Parameter simulation at 2.5 GHz.
Figure 1 - Quadrax 3D view
Through this simulation, we aim at finding the frequency responses of the device: basically insertion and return losses. An S-Parameter simulation provides what is intended here: The frequency plan is discrete with a thin step between 100 MHz and 2.5 GHz. We will be able to view the propagation of the wave within the quadrax and measure the field intensity in or along user-defined curves within the shape.
The quadrax has two ports on the two lateral sides of the transmission paths. The propagation is in the TEM mode. We have four signal boundary conditions with a perfect electric conductor at outer face of the quadrax.
At the desired user-defined center-frequency, we can view the electric and magnetic field in different settings: i.e. iso and section clipping, animated through varying its omega-T phase, modified colors chart... . Here is a spotted capture of the electric field distribution on the surface of the quadrax's outer face.
Figure 2 - Near field distribution
We can also check the field inner distribution by using the iso or section clipping feature (See next figure)
Figure 3 - Inner Electric field distribution
Figure 4 - Insertion/ Return loss
The return and insertion losses are in a good range and meet the expectations and measurements of the manufacturer. As mentioned earlier, we can go for further results and investigate every single point by probing it on a 3D electric field plot. Here is an example of the electric field variation from the central axis towards the lateral face: the X-axis is numbered using the ordinal numbers of the nodes in the created mesh.