A single Central Unit can be connected to multiple Distributed Units. CU-CP will have RRC, PDCP CU-UP will have SDAP, PDCP Distributed Units will include RLC, MAC, H-PHY. F1 interface is used to cinnect between DU and CU. eCPRI is connected to H-PHY and L-PHY. CPRI …
In previous chapter we shall learned about RRU, BBU, CU, DU fronthaul, midhaul; In this chapter we shall learn about: D-RAN C-RAN cloud RAN vRAN oRAN D-RAN vs C-RAN vs vRAN vs O-RAN What is D-RAN? DRAN stands for “Distributed RAN”. In this type, RRU and …
Fronthaul, Midhaul and Backhaul are used to connect RU, DU and CU and the core network together. They tells us about the transport network architecture. What is Fronthaul ? It is the link between RRU and BBU. or RRU and DU. It has a latency requirement …
PDCCH Order will be initiated by network to trigger a Random Access procedure. This is initiated when there is an upstream loss. When gNB has downstream data to send, PDCCH order will be used to initiate RACH and get up-stream synchronization. PDCCH order uses PDCCH DCI …
UE access procedure is as below: Step 1: UE is Switched ON Step 2: PLMN Selection PLMN Introduction PLMN stands for Public Land Mobile Network, will be established by the network and is used to provide land mobile communication services to public. PLMN = MCC + …
Cell Search and Cell Selection 1. When a UE is powered on, it searches for a specific frequency according to Synchronization Raster as defined in TS 38.104. 2. UE tries to detect PSS/SSS to get downlink synchronization and get the PCI of the cell. 3. UE …
In this previous chapter we learnt about 5G NR initial access process in brief. In this chapter we shall see the important message contents. 1. RRCSetupRequest: UE sends a setup request IE: ue-Identity / establishmentCause Channels: CCCH, SRB0 2. INITIAL UL RRC MESSAGE TRANSFER gND-DU …