The current trend towards the Multimediazation in the car cabin is remarkable. Adding to the existing car audio systems, Navigation, RBDS (Radio Brordecast Data System), DAB(Digital Audio Brordcasting), Cellular phone and other digital media are likely to be incorporated into the new car entertainment system, which shall also provide expandability for new media in the future.
The recently proposed control bus systems are mainly designed for car operations which are not suitable for audio systems in terms of transfer rate, datalength, and cost. And the mainstream concept is that the audio control bus line should be separate from the standpoint of safety.
However, there is still no standard car entertainment bus, car and car audio makers continue developing their own format. This causes over investment in development of audio systems, inefficiency of designing, and difficulty in cost reductions.
We also have to consider cost merit for component units as a larger scale of car entertainment systems.
We developed a new bus system(IP-BUS)which enables us to organize a large car entertainment system easily.