5G
5G NR fundamentals through advanced RAN and core topics: architecture, protocols, scheduling, and more.
Non-Terrestrial Networks: 3GPP Satellites, Delay Budgets, and Direct-to-Device
How 3GPP adapted NR for satellites: LEO/MEO/GEO trade-offs, the timing advance and HARQ changes long delays forced, transparent versus regenerative payloads, and what direct-to-device really delivers.
What Is 5G NR? Numerology, Frequency Ranges, and the Flexible Frame
5G NR explained for engineers: scalable numerology, FR1 and FR2, the flexible slot structure, bandwidth parts, and what actually changed from LTE.
5G Interview Questions: What Gets Asked and How to Answer It
A structured 5G interview guide: the questions that actually come up across radio, RAN, core and QoS, worked troubleshooting and system-design scenarios, and a framework for answering well.
5G Scheduling Algorithms: Round Robin, Proportional Fair, and What Real Schedulers Do
How the gNB MAC scheduler decides who transmits: the classic algorithms, why Proportional Fair became the baseline, and how QoS-aware scheduling handles URLLC and eMBB together.
RRC States in 5G: Why RRC_INACTIVE Exists
The three NR RRC states explained: what IDLE, CONNECTED and INACTIVE each cost in power and latency, and the specific problem RRC_INACTIVE was designed to solve.
5G RedCap: Filling the Gap Between NB-IoT and Full 5G
What RedCap actually reduces — bandwidth, antennas, duplex and processing — which devices it targets, and how it compares to LTE Cat-1, eMTC and NB-IoT.
5G QoS Flows: 5QI, ARP, Reflective QoS, and How Policy Reaches the Air
A deep dive into the 5G QoS model: what 5QI actually specifies, how GBR and delay-critical GBR differ, the role of ARP and Session-AMBR, and how reflective QoS avoids signalling.
PDU Sessions in 5G: What They Are and How QoS Rides on Top
A PDU Session is the 5G Core's unit of data connectivity. Here's how one gets established, what lives inside it, and how QoS Flows map down to radio bearers.
NSA vs SA: The Two Ways to Deploy 5G, and Why It Matters
Option 3x versus Option 2 explained: how NSA anchors 5G on LTE, what SA unlocks with the 5G Core, and which 5G features simply do not exist on an NSA network.
5G Network Slicing: S-NSSAI, Slice Selection, and What Actually Gets Reserved
How 5G network slicing works end to end: S-NSSAI structure, NSSAI types, the registration-time selection procedure, and why requesting a slice is not the same as getting resources.
Massive MIMO: Where the Capacity Gain Actually Comes From
How massive MIMO multiplies 5G capacity: spatial multiplexing versus beamforming, why MU-MIMO is the real gain, what 64T64R means, and why TDD reciprocity matters so much.
HARQ in 5G NR: Soft Combining, Process IDs, and Flexible Timing
How HARQ combines FEC with retransmission, why soft combining beats plain ARQ, and what NR's K1/K2 timing flexibility changes for latency and URLLC.
The gNB Explained: CU/DU Split, Interfaces, and What Changed from the eNB
What a gNB actually is: the CU/DU functional split, the F1, E1, Xn and NG interfaces, how it differs from an LTE eNB, and the deployment models operators actually use.
Dual Connectivity: EN-DC, Bearer Types, and Talking to Two Nodes at Once
How dual connectivity works: master and secondary nodes, the four MR-DC variants, MCG/SCG/split bearer types, and why DC tolerates backhaul that carrier aggregation cannot.
Carrier Aggregation in 5G NR: PCell, SCells, and Why Throughput Doesn't Just Add Up
How 5G NR carrier aggregation works: component carriers, the PCell/SCell relationship, intra- and inter-band types, and why aggregate throughput rarely matches the sum of the parts.
Beamforming in 5G: Analog, Digital, Hybrid, and Keeping the Beam Aligned
How 5G beamforming works: array gain, the three architectures and their RF-chain economics, SSB beam sweeping, and why beam management is a continuous process.
AMF vs SMF vs UPF: Who Does What in the 5G Core
A side-by-side breakdown of the three central 5G Core functions: what each one owns, how they interact during registration and session setup, and why the split matters for slicing and edge.
AI-RAN: What Changes When the Radio Network Learns
AI-RAN explained for RAN engineers: the three meanings of the term, where machine learning genuinely beats rule-based automation, and the compute and reliability problems in the way.
5G Core Architecture: The Service-Based Design Explained
How the 5G Core works: service-based architecture versus point-to-point reference points, the network functions and what each does, control/user plane separation, and how slicing falls out of the design.