150 Mbit/s MOST, the Next Generation automotive infotainment system

Summary form only given. MOST is a successful network solution for infotainment systems in cars. It provides an efficient synchronous network for streaming data as well as for asynchronous packet data with low administrative overhead. MOST25-systems (25 Mbit/s) using an optical physical layer and MOST50 (50Mbit/s) using electrical transmission are now widely spread in the automotive world. New audio and video applications in cars force the implementation of new high speed infotainment networks. This gave rise to the new 150 Mbit/s version of the MOST network, MOST 150. This paper highlights possible applications and features of the newly specified MOST150, such as an isochronous transport mechanism to support video applications, and the "Ethernet channel" for efficient transport of IP-based packet data. The first Physical Layer Specification for MOST150 defines an optical solution, which allows carmakers to speed up their existing MOST25-networks and to continue in using POF in the wire harness and LEDs as light sources. They can go on with their established optical wire harness and assembly processes which make the transition to higher bandwidth infotainment networks with MOST 150 a smooth evolution. A new approach of the MOST150 Physical Layer Specification was to define standardized packages together with pin-out descriptions for optoelectronic converters additionally to the electrical and optical signal parameters. The standardization of packages addresses the development of optical components, compatible with modern electronic-production processes. It reduces the supply chain and simplifies the handling of multiple supplysources for such optical components on TIER1-level. Based on lessons-learned of today's MOST25 optical modules, this paper describes the motivation for combining transmitter and receiver into a transceiver-design and choosing an SMD -package. Pro and Cons will be discussed as well as the capability of this new package concept to serve for other data rates and emitter/receiver technologies. Daimler AG , together with other premium manufactures, is working in the MOST Cooperation to specify a suited data bus for high speed infotainment networks. Since 2006 the Daimler AG is investigating the MOST150 optical data bus for usage in automobile environments. In the course of the year 2009 the decision about a series introduction of 150 Mbps MOST within Daimler cars is expected.