LTE: Why does MIB transmit only on "sub frame 0" of each radio frame ?

Question

I mean to say, why does MIB transmit only on sub frame 0 not on other sub frames of same radio frame ?

Answer 1

When the UE has obtained the slot after decoding PSS, the best case scenario is the UE figured out the Frame boundary(using SSS) in Subframe 0(which happens in slot0), in which case it can immediately(in the slot1 of subframe 0) obtain the MIB info. The worst case (or the only other) scenario is that it figures out in the subframe 5, in which case it has to wait another 5 subframes for the Frame start.
Once it obtained the Frame boundary, it makes sense to finish the MIB decoding in the subframe 0 itself, rather than waiting for another 5ms.

Comments

Nice explaination.........

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But I have a doubt here that UE first reads PSS from 7th symbol in slot 0 of subframe 0 then UE reads SSS from 6th symbol in slot 0 of subframe 5  right ? so does it mean UE obtains MIB info from subframe 5 or subframe 0 ? Is there a possibility that UE reads SSS info from 6th symbol of subframe 0 itself after reading PSS as 7th symbol in subframe 0 ?
Please correct me if my understanding is wrong somewhere !!