• Vision
  • About us
  • LTE RANDOM ACCESS PROCEDURE

    lte random access procedure random access procedure lte random access random access 5g random access 5g random access procedure random access memory ram random access memory random access memory meaning rach procedure in lte serial access memory access memory types of random access memory random access memory in hindi random memory random access memory meaning in hindi magnetic random access memory random access memory is random access in computer networks ram random examples of random access memory faster random access memory lte preamble sequential and random access lte msg3 about random access memory random access and sequential access java randomaccess msg3 in lte rach process in lte preamble lte random access memory adalah sequential access and random access physical random access channel random access memory price ra rnti calculation in lte random access memory in digital logic design random access memory in tamil random access channel lte ddr ram full form in computer the random access memory random access sequential access semi random access memory random access in lte s ram full form in computer computer random access memory random access memory ppt rom random access memory direct random access access randomize rach preamble in lte parameter random access memory meaning of ram and rom in computer random access in data communication 5g nr random access procedure use of random access memory ram random access random data access s random access memory different types of random access memory serial access memories card random access memory apa itu random access memory first random access memory random ram double data random access memory random number access contention based rach in lte double data rate random access memory delta preamble msg3


    RAP(Random Access Procedure)
    Random Access procedure is essential part of for LTE protocol communication and used for getting the grant of Uplink resources for sending RRC message first time so that UE will attached to Network. So Here I tried to provide you RAP step wise step.
    lte random access procedure, random access procedure, lte random access, random access, 5g random access, 5g random access procedure
    RA Procedure Messages with Timers

    1.     UE MAC(refer Ans 1) select a preamble out of the available 64 preamble randomly(0-64) either contention based or Non contention Based.
    2.     UE MAC gives this preamble to UE physical for dispatch.
    3.     UE MAC tells UE physical about which PRACH resource(refer Ans 23) should be used for preamble sending.
    4.     UE Phy transmit the preamble on the selected PRACH resources.
    5.     Before Transmission UE physical calculate RA-RNTI (refer Ans 36).
    6.     eNB physical received preamble on PRACH resource and calculate RA-RNTI first.
    7.     eNB phy forward the preamble to eNB MAC.
    8.     eNB MAC allocate UL resource for the UE and this information forwarded to UE.
    9.     eNB MAC prepares a message called RAR(Random Access Response) with the following detail:
    a.     Preamble ID
    b.     PUSCH PRB
    c.     T-C-RNTI
    d.     Timing Advance
    lte random access procedure, random access procedure, lte random access, random access, 5g random access, 5g random access procedure
    RNTIs


    10.  This RAR must be sent to UE on PDSCH channel by reserving PRB.
    11.  eNB MAC allocate a PRB for the UE on PDSCH and gives these details [RAR+PDSCH PRB] to eNB physical.
    12.  First eNB phy have to send the PDSCH PRB reservation detail to UE on the PDCCH channel against RA-RNTI.
    13.   eNB PHY pack RAR info on PDSCH PRB and transmit it.
    14.  UE PHY always listening to PDCCH to get to know that there is any PRB allocates against his RA-RNTI on PDSCH.
    15.  UE PHY download the specified PRB and decode the info and send it to UE MAC.
    16.  UE MAC received RAR which contain many detail .
    17.  UE MAC verify the preamble id if matched than UE MAC decided to send “msg3”.
    18.  “msg3” is nothing but a RRC connection request message.
    19.  UE MAC send msg3 to UE PHY along with PUSCH PRB used for transmit.
    20.  Also MAC tells physical layer about how much timing advance must be applied before Tx.
    21.  UE PHY Tx “msg3” by coding into PUSCH PRB indicated.
    22.  eNB PHY received this and send to eNB MAC.
    23.  eNB MAC will perform the below task:
    a.     Send ACK in the name of CRI(refer Ans 19) to UE that I have received msg3.
    b.     Send msg3 to higher layer.
    24.  eNB reserve a PRB for the UE on the PDSCH against T-C-RNTI to send CRI and send it.
    25.  UE MAC compare the CRI received with Tx msg3, if equal than RAP is successful otherwise failed.

    Jitendra Kumar

    Author & Editor

    2 comments:

    Please feel free to ask your's doubts or questions in below mention comment section box..!!