Difference between PUCCH and PUSCH

I was asked by many engineers on PUCCH and PUSCH functionality and major difference.

This thread describes PUCCH functionality and PUSCH functionality.

I have tried to differentiate major difference between PUCCH and PUSCH where possible.After reading entire post reader can conclude PUCCH vs PUSCH.

PUCCH : 
  • The Physical Uplink Control Channel (PUCCH) is used to transfer Uplink Control Information (UCI).
  • UCI can also be transferred using the PUSCH. Please referDifferent Channel State Information (CSI) Reporting Types.
  • The release 8 and 9 versions of the 3GPP specifications do not allow an individual UE to transmit both the PUCCH and PUSCH during the same sub frame.
  • For Release 8 and 9 if UE has application data or RRC signalling than UCI information transmitted via PUSCH.
  • The release 10 version of the 3GPP specifications introduces the option to support simultaneous PUCCH and PUSCH transmission.
  • 3GPP specify 7 PUCCH formats.Different PUCCH formats are 1,1a,1b,2,2a,2b,3.
  • The PUCCH is able to transfer various combinations of Scheduling Requests (SR), Hybrid Automatic Repeat reQuest (HARQ) acknowledgements and Channel State Information (CSI) reports. CSI reports can include Channel Quality Indicators (CQI), Precoding Matrix Indicators (PMI), Precoding Type Indicators (PTI) and Rank Indications (RI).
    • PUCCH formats 1, 1a and 1 b transfer HARQ acknowledgments and scheduling requests.
    • PUCCH formats 2, 2a and 2b transfer HARQ acknowledgements and CSI reports.
    • PUCCH format 3 transfers HARQ acknowledgments for carrier aggregation and scheduling requests.
PUSCH
  • The Physical Uplink Shared Channel (PUSCH) is used to transfer.
    • RRC signalling messages
    • Application data
    • Uplink Control Information (UCI).
  • RRC signalling and UCI represent additional overheads from the perspective of transferring application data (additional to the overheads generated by the Reference Signals, PRACH and PUCCH).
  • The PUSCH can be modulated using 64QAM, 16QAM or QPSK. The eNode B selects the appropriate modulation scheme according to its link adaptation algorithm.
  • The PUSCH always uses QPSK when TTl Bundling is enabled.
  • If UE does not support 64QAM and eNodeB instruct to use 64 QAM then 16 QAM is selected.

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