I have been working a with relatively fast and high end microcontrollers now, and I want to move beyond them. For example, I've been using the STM32F4 chip, which has something of a 180MHz and a decent amount of memory. Now I want to move beyond these "high end" microcontrollers. I want to develop platforms which are in the GHz-range, which can manage a lot of calculations, and also work together with an embedded GPU. The application I want to use it for is in the automotive industry, where there's a lot of data processing and algorithm calculations.
As I understand it, the next step is somewhat more complicated. You need a separate memory, RAM, storage, and a lot of other peripheral components to support the chip. I'm not looking for an embedded computer platform like the beagleboard or RBP, where you run an OS. I would like to run an RTOS where you can crunch decent amount of numbers (lidar data, image processing), and manage real-time requirements.
For example, if some tech company which develops autonomous vehicles wanted a prototyping platform (and I say prototyping cause it would probably be an ASIC in production) where they can do a lot of dataprocessing and algorithms, what type of embedded system would they use?
So my questions is: What lies beyond the high en microcontrollers? Could someone give me an overview of how embedded systems are built up in this domain?