Issue link: https://te.mouser.com/i/1349092
TE Connectivity Trend Paper /// Connectivity for Next-Generation Mobility Page 10 Connectivity for Next-Generation Mobility 4.3 Reliable High-Speed Data Connectivity in an All-Electric Environment EMC is a branch of electrical engi- neering which seeks to eliminate the unintentional creation and reception of electrical energy, which can cause unwanted effects such as electro- magnetic interference and in ex- treme cases, even physical damage to sensitive electrical equipment. Within automotive engineering, EMC is not a new field. Since the installa- tion of the first radios within vehicles, engineers have sought to reduce in- terference to radio signals to max- imize the listening experience for passengers. However, the safety of next-gener- ation fully autonomous vehicles will depend on data coming from an ar- ray of cameras, sensors, and radar to detect traffic lights, read road signs, monitor other vehicles, and take de- fensive measures to avoid pedestri- ans and other obstacles in the path of the vehicle. At the same time, seamless cloud-based infotainment via applications such as CarPlay and Android Auto, larger displays, and user-friendly control systems are already creating a more enjoyable connected passenger experience. Therefore, next-generation vehi- cles—and their system—will require ultra-reliable, fail-operational high- speed data connectivity. Managing EMC performance is key to achieving this goal. In this regard, integrating electric drive trains into vehicle architectures represents a substantial challenge. It means low voltage data connectivity networks and high voltage (HV) drive systems must work ultra-reliably and safely in parallel. OEMs must minimize energy emissions, which can cause electro- magnetic interference (EMI) from high voltage powertrain systems as well as minimize the data connec- tivity links' susceptibility to these emissions. In respect of the physical data trans- mission layer, there are several cable options. Differential Cables Differential signaling cables are con- structed from copper. These wires are often considered an attractive choice for connectivity, because of their relative low cost and ease of use. OEMs create these cables by twisting two insulated wires around each other, enabling one of them to act as the return path for the oth- er. This improves their EMC perfor- mance. It also means they are a good solu- tion for bi-directional data transmis- sion, for example, between on-board computers and ECUs. However, dif- ferential connectivity is more com- plex if contact points are shielded, requiring additional processing. There are two main types of differ- ential cables: Shielded twisted pair (STP) cables shield each pair to further protect data transmission from experiencing EMI from other wires in close prox- imity, particularly when higher rates (bandwidth) are involved. Unshielded twisted pair (UTP) ca- bles do not contain extra shielding, meaning that they can be a more economical solution, especially for lower data rate requirements. How- ever, they are also prone to interfer- ence, which can potentially affect performance. UTP is more widely used due to low- er cost, greater manageability, and absence of grounding issues. STP is more expensive, heavier, and increases complexity because it must be grounded. However, its inability to handle high EMI/EMC constraints can make UTP a more restrictive option. This is one of the challenges of Ethernet technology whereby OEMs must balance trans- ceiver and physical complexity, de- ciding if bandwidth/connectivity is more important than overall cost and efficiency. Coaxial Cables Coaxial cable is able to support high- er bandwidth. It's a robust, shielded option, which makes it resilient to EMI, and is often used in today's ve- hicles. However, its EMI protection is limited by the fact that the return path for the high-frequency current resides in the shield itself. This is es- pecially true when the connected de- vice contains multiple transceivers, since parasitic (capacitive) effects can burden the radio frequency (RF) shield. However, in recent years, sig- nificant design improvements have meant coaxial cables are now fre- quently deployed in today's vehicles. Optical Fiber Based on light, optical fiber is com- pletely immune to electromagnetic interference from electromagnetic Next-generation vehicles— and their system—will require ultra-reliable, fail-operational high-speed data connectivity