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88 Focus | Infotainment systems technology for fibre optic transceivers and license it to chip designers and connector makers to create a wide range of suppliers. The additional challenge is that this needs two separate standards: one for Ethernet as part of IEEE 802.3 for the 25 Gbit/s modulation and a separate ISO standard for the connectors. Automotive qualification to the AECQ standard for these devices is planned for the beginning of 2024 for vehicle production, following samples of silicon at the start of 2023. A second standard will be for between 50 and 100 Gbit/s but should use the same ISO connector technology. This can carry the Ethernet packets or TTEthernet protocols in the same way as copper wires. Copper at 25 Gbit/s The camera and sensors for autonomous driving are already pushing the performance envelope, with 4K/8 MP cameras going beyond 4 Gbit/s, and this is pushing automotive networks to work at much higher speeds. If the cameras are to drive multi-gigabit data rates then the backbone has to run at much higher speeds; this is driving demand for a 25 Gbit/s backbone inside the car for designs in 2023 and 2024. That will be necessary to carry data from 5G radio links. There is a standard for 2.5-10 Gbit/s on a single STP with IEEE 802.3ch that is almost complete. Meanwhile, 25 Gbit/s technology over copper STP cable is in development at the NAV Alliance. The NAV Alliance includes some of the major platform developers as well as subsystem and connector suppliers, and has five technical working groups. Some of these are developing the 25 and 50 Gbit/s Automotive Ethernet PHY specifications, the physical layer system and component integration, as well as the EMI requirements and the limits at these speeds. Other working groups are looking at protocol encapsulation for Ethernet and system controls and management. The aim is to move the 25 and 50 Gbit/s development to the IEEE for standardisation in the next 12 to 18 months, ready for deployment in 2023 and 2024. All this is based on a single STP cable rather than optical fibres, to avoid problems with humidity and vibration that can reduce the performance of optical cables. Security With more data running around the vehicle, security is an increasingly important factor for the network. An Ethernet intrusion detection system can be added to switches to detect malicious activity at the network and application layers. This runs on a multi-core network processor that sits alongside an Ethernet switch chip to identify this activity, which would otherwise be missed. The chips then report intrusions to the car maker’s security centre, allowing the event to be analysed and managed across all the vehicles. This requires higher performance from the network processors and Ethernet transceivers. The latest processors for designs being April/May 2020 | Unmanned Systems Technology One use for autonomous vehicles is as a mobile office, but that requires higher data rates in the automotive bus design than in current cars (Courtesy of Mercedes-Benz)