5G
Learn about 5G DMRS for PBCH (1) What is the primary function of DMRS for PBCH? * The UE uses DMRS to estimate the propagation channel experience by the PBCH. The resultant information is used to demodulate the PBCH and subsequently decode the Master Information Block. (2) How and where is
5G
What are 4G S-TMSI and 5G S-TMSI? * 4Gย ย S-TMSI, and is part of GUTI, it is used to identify a UE within a specific MME Pool. * 5Gย S-TMSI can be used to identify a UE within a specific AMF Region. How can you trace and check them? * In 4G: It
5G
๐ก What is it? PDSCH Multiplexing simply means leveraging the free resources within the PDSCH DMRS Symbol for optimal PDSCH utilization. ๐Expected Gain: Experience an increase in the maximum user throughput for users in good radio conditions. ๐ซ Expected Drawbacks: There's always a tradeoff. Be mindful of the impact on
5G
The Channel State information (CSI) Reference Signal is a multi-purpose DL Transmission. The Base Station can configure the UE to use the CSI-RS for one or more of the following: 1- CSI Reporting As seen in the below figure, the g-NB initially will send the related configuration and transmit CSI
5G
* The 4G/5G Globally Unique Temporary Identifier (GUTI) is a temporary identity used by the network to enhance privacy. The MME assigns it in 4G or AMF in 5G, and the allocated GUTI can be changed at any time by MME/AMF. * 4G GUTI has three components. Where: * PLMN identity
5G
5G CSI-RS has 3 Types: 1- Non-Zero Power CS RS is used for two main purposes ย - For Channel Measurement CSI reporting, Beam Management, RLF, Beam Recovery, and Mobility. ย - For Interference Measurement, โIntra-Cell Interferenceโ is mainly used to measure intra-Cell interference generated by Users during Multi-User MIMO 2- CSI
5G
What are the common 5G NSA Mobility Common Handover failures Root-Causes? (1) Missing X2 Definition/Missing Neighbors * Unlike legacy 4G handover scenarios, where missing neighbors may cause quality issues or call drops but not affect the handover KPIs as the handover attempt will not be initiated at the first place
5G
Did you know that 5G SRS can be configured with either a full-band SRS bandwidth or a narrow-band SRS bandwidthโ - Purpose of SRS: Let's revisit the basics. SRS serves uplink channel measurement, time-frequency synchronization, and beam management. - Advantages and Disadvantages: So, what are the primary pros
5G
๐ช๐ต๐ฎ๐ ๐ถ๐ ๐๐ต๐ฒ ๐ฝ๐ฟ๐ถ๐บ๐ฎ๐ฟ๐ ๐ณ๐๐ป๐ฐ๐๐ถ๐ผ๐ป ๐ผ๐ณ ๐ฃ๐๐๐๐ ๐ถ๐ป ๐ฑ๐ โ โ Before going into details, You just need to understand that PDCCH is the heart of the Air-interface as it is being used to allocate and inform the UE about all the Scheduling information needed to start using any service. โIn addition to this, Proper optimization of the PDCCH resources is
5G
What's 4G&5G Allocation and Retention Priority (ARP)? How do you inspect it in traces, and what are its use cases โ Definition: Allocation and Retention Priority (ARP) in both 4G and 5G refers to the priority level assigned to a user or device within the network. This
5G
What is T304 Timer? and How does the UE detect a Radio Link Failure based on this timer configuration โ * T304 Governs RRC Reconfiguration Procedure for the HO, Simply means that If the UE does not complete the handover before this timer expires, the UE reverts back to the associated configuration
5G
How does the UE detect a Radio Link Failure โ * Understanding this part is key, especially when troubleshooting or improving 4G & 5G retainability. It helps you know how the UE spots a radio link failure, which is vital for pinpointing issues. Plus, it gives you confidence when adjusting UE-related timers