top button
Flag Notify
Site Registration

Why do we have to use predefined Transport Block sizes?

+2 votes
502 views

Why can't we just calculate total the amount of data, which is to be send using amount of available REs for data transmission, code rate and modulation?

posted Jun 17, 2014 by Dilbagh

Share this question
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer

0 votes

Due to the trade-off we need to take into account while designing a system. The trade-off need to answer the question: how detailed the scheduling info is? If we would need to tell the UE explicitly exact number of bits we send in the transport block, that would be a huge amount of data seen as signalling. Therefore we have a limited number of options for transport block size, so that we may use low number of bits to point to one of these options.

answer Jun 18, 2014 by Sidharth Malhotra
Similar Questions
+2 votes

As for uplink resources we know we need to know before that how much data UE has to send and how much is in buffer. That is ok but how can we predict the data rate for that data?

+1 vote

As far as I know eNodeB calculates the number of Physical Resource Blocks allocated to each UE, based on the specific metric, then takes the minimal modulation and coding scheme to deduce the transport block size that must be allocated to each user, Why this minimal MCS ? Isn't it too sub-optimal?

+1 vote

How can we calculate the transport block size given the MCS index and the number of used PRBs as defined in the 3GPP table 36.213.

+2 votes

In case of Rel 10 supported(Carrier Aggregation) eNodeb, how does the enodeb decide as to through PDCCH of which cell UL Grant is sent ?

...