4g LTE: LTE MAC: Random Access Procedure and RACH
Introduction: RACH stands for Random Access CHannel. UE will perform power on procedure for DL synchronization. UE will perform RACH procedure…
4g LTE: LTE MAC: Scheduling
MAC Scheduler is used to assign bandwidth to UE in uplink and downlink channels. eNB will decide for which UE how many resources to be…
4g LTE: LTE MAC CE: DRX Command
WKT UE will receive downlink data over PDCCH. So UE has to monitor PDCCH everytime to check if there is any downlink data available. By doing…
4g LTE: LCP Logical Channel Prioritization
Before we learn about Logical Channel Prioritization (LCP), we need to learn about channel starvation. Channel Starvation: Before LCP, every…
4g LTE: dlInformationTransfer, ulInformationTransfer and ulDirectTransfer
dlInformationTransfer Direction: eNB => UE Signalling Radio Bearer: SRB2 or SRB1 RLC Mode: AM Logical Channel: DCCH Transport Channel:…
4g LTE: LTE MAC UL CE: BSR
BSR is a MAC UpLink control element. Truncated BSR LCID value is “11100” in binary and 28 in decimal Short BSR LCID value is…
4g LTE: LTE MAC: Understanding MAC PDU
Below is the MAC PDU structure: From the above image we can see that, one MAC PDU has 2 parts 1. MAC Header 2. MAC Payload. Mac Header can…
4g LTE: LTE MAC UL CE: Power Headroom Report
Power Headroom Report (PHR) is a MAC Uplink Control Element. LCID value is “11010” in binary and 26 in decimal * Every UE will…
4g LTE: LTE NAS layer introduction and procedures
NAS layer : Non-Access Stratum: This is used to communicate control plane information between UE and MME. NAS layer protocols functions are to…
4g LTE: LTE security flow
In this chapter we shall see the keys exchanged between different procedures. Below security flows is a smaller part in LTE Attach Request. To…