4G/LTE - PHY Channel





PDSCH (Physical Downlink Shared Channel)


PDSCH is a physical channel that carries user data.

  • Carries user specific data (DL Payload).
  • Carries Random Access Response Message in case of PDSCH mapped to RACH channel.
  • It is using AMC with QPSK, 16 QAM and 64 QAM. The modulation scheme for each PDSCH for each user is determined by MCS value in DCI.


In terms of channel processing, PDSCH is going through the most complicated process. If you understand full details of PDSCH channel processing, you can say you have understood almost everything of LTE Physical Layer, implying that it would be almost impossible to describe everything in single page without boring you out.


Refer to Channel Coding Processing for DL SCH/PCH/MCH for step (1)~(5). Refer to Precoding page for step (8),(9).

If you are also interested more in Step (8),(9) in terms of Antenna Configuration, Refer to PHY Processing page.

If you want to have some more intuitive understanding and try follow these steps on your own, Refer to Matlab : Toolbox : PDSCH.