Why do we have to use predefined Transport Block sizes?

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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

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1 Answer

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

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