4 ms·
There are real time requirements on the protocol handling so you can't just send "raw" L1 transport blocks up to the AP.
by kristoffer 12y ago
There are real time requirements on the protocol handling so you can't just send "raw" L1 transport blocks up to the AP.
- Zigurd 12y agoI wasn't thinking of pulling the layer 1 up into the AP. But I don't know... do you have such requirements anymore? You have real time requirements for voice calls in 2G/3G hard handover. If you treat everything as if it were a vertical handover, I think you can even wash that requirement out. And you can fudge the perceived voice call continuity.
- kristoffer 12y agoYou have real time requirements in L2 (MAC) in LTE with e.g. HARQ with 4 ms to provide ack/nack. Might not be so hard to achieve but still real time.
- Zigurd 12y agoHARQ is a soft real time requirement, and 4ms is within what you can get in Linux interrupt response. That is, it's not going to force you to do hard real time hacks in your AP. Anyway, the real question is: Can you build a 4G radio you can trust because it does little enough that it can have open firmware and driver and protocol software that takes less than 10 years to write? I think the answer is "Yes. Maybe simpler than 2G." Or at least "Much more likely than with a 3G radio."