Many thanks for your comments.
Regarding the (CQI ,RI and PMI). Just I want to know the steps of calculation for these reports and their format (in bits or real value ) and the names at each stage :
here my understanding:
At the UE:
Regarding the CQI report , the UE calculates the SNR value and then send this value in form of bits to the base station (BS) in wireless channel.
At the BS:
The value of CQI which in bits will estimated by the channel estimator and then from the table of the CQI the BS will know the required modulation and coding scheme (MCS). Then this value is used by the scheduler to increase or decrease MCSs. After that the BS will inform the UE about the new change ( here at this stage I don’t know what the BS will send to the UE as a feedback value?).
Regarding the RI and PMI I don’t know if they work in the same manner just like the CQI or not?
Please clarify for me how the process of exchanging this information happen between the UE and BS.