Dear all,
Most mobile phones contain an ARM-like application processor AP for general user applications and a base band processor for the radio software stack, could you please elaborate on the following:
1. Do the AP and the baseband processor communicate somehow? is it possible to access the AP from the baseband or the baseband from the AP.
2. What is actually the baseband processor: is it typically an ARM-like processor hosting a RTOS that service a Radio software stack such as GNU radio, or it more like a simple microcontroller with appropriate hardware accelerators
3. Is it possible to implement the modem functionalities of the baseband processor (Radio software) in a separate high priority real-time VM on the Application processor.
Please share your experience.
Best wishes.
Yes, how else does the applications processor tell the modem that you want to make a phone call, of visa verse when you have an incoming call.
Needs a lot more DSP processing power than a typical Cortex-M MCU - often something like a Cortex-R4. Some baseband designs use multiple processor cores - typically tightly coupled to some interface to talk to the analogue world (on chip or off chip, whereever it may be).
In theory yes - the majority is just software so anything is _possible_ - the question is how easy / economical to develop?
HTH, Pete
Thank you so much for your very helpful answer.
Could you please route me to a document that explains in details what type of interconnect/bus/protocol is used for data exchange between the AP and the baseband is there any memory that is shared between the AP and the baseband or there is much like an interrupt based mechanism for notification etc...
Many thanks for the clarification.