When I read "cores" I think "on the same chip," so that took some re-reading to parse. Handling the radio is the job of the baseband processor, which has its own RAM and firmware, in a separate package from the CPU. It looks like, as of the iPhone 5s, it's still a separate processor. I think that the vagaries of FCC licensing will keep it separate; otherwise, you'd have to re-test it for interference whenever you rev'ed your CPU or perhaps even firmware. I think most baseband firmware is proprietary and tightly controlled; for the paranoid, it presents an attack surface that's very hard to examine.
I've not seen any phone with a baseband on the same chip (or at least, that shared any of the resources of the primary cpu. FCC rules makes that, as the GP mentioned, extremely tricky if possible at all.
What phones have you seen that do have a integrated baseband?
As for FCC rules, in general it's safe to assume that the regulated are smarter than the regulators. The baseband core is probably "logically separate" or something to meet FCC regulations.
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When I read "cores" I think "on the same chip," so that took some re-reading to parse. Handling the radio is the job of the baseband processor, which has its own RAM and firmware, in a separate package from the CPU. It looks like, as of the iPhone 5s, it's still a separate processor. I think that the vagaries of FCC licensing will keep it separate; otherwise, you'd have to re-test it for interference whenever you rev'ed your CPU or perhaps even firmware. I think most baseband firmware is proprietary and tightly controlled; for the paranoid, it presents an attack surface that's very hard to examine.
Basically only the iPhone has a separate baseband chip; most other phones put the baseband on the same chip as the application processor.
I've not seen any phone with a baseband on the same chip (or at least, that shared any of the resources of the primary cpu. FCC rules makes that, as the GP mentioned, extremely tricky if possible at all. What phones have you seen that do have a integrated baseband?
Any that use a Qualcomm chip.
As for FCC rules, in general it's safe to assume that the regulated are smarter than the regulators. The baseband core is probably "logically separate" or something to meet FCC regulations.