5G Baseline & NTN Foundation

Establish only the 5G architecture needed to reason about NTN, then introduce why NTN exists, the platform types, and the full 3GPP NTN standardization roadmap up to Rel-19 and the road to 6G.

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Day objective — the minimum 5G SA architecture, the NTN “why”, and a release-anchored roadmap you can navigate. Pick a sub-topic on the left — it opens here on its own.

1.1

5G in One Half-Day: What NTN Builds On

The minimum terrestrial 5G architecture you need before adapting any of it for satellite — the system, its reference points, and the control/user-plane split that NTN payloads lean on.

Pick a sub-topic — the ones with › open their own animated deep-dive page:

Service categories — eMBB, URLLC, mMTC and where NTN realistically fits today
SA vs. NSA — why NTN focuses on standalone (SA) / 5GC
End-to-end system — UE, gNB, 5GC, Data Network; N1 / N2 / N3 / N4 / N6 reference points
CUPS — control / user-plane separation and why it matters for satellite payloads
Registration & PDU-session flow at a glance (full message capture happens in the lab)

1.2

5G Core (SBA) — NTN-Relevant View

Just the Service-Based Architecture concepts NTN later builds on — the network functions, where the UPF can live, and the slice identifiers used for TN/NTN continuity.

Pick a sub-topic — the ones with › open the interactive React-Flow deep-dive:

5G Core (SBA) — the whole view — one animated page: the SBI bus, every NF, direct vs. proxy communication, slicing, and where the UPF can fly
Service-Based Architecture — HTTP/2 + REST/JSON; NRF registration & NF discovery
Key NFs & NTN relevance — AMF · SMF · UPF · AUSF · UDM · NRF · PCF · NSSF · NEF
UPF placement — central, edge, and (Rel-19) onboard — introduced here, planned on Day 4
Network slicing — S-NSSAI · SST · SD used later for TN/NTN slice continuity

1.3

5G RAN — gNB Structure Before NTN Adaptation

The terrestrial gNB split and air-interface essentials — the exact structure that shaped the NTN payload debate and the protocol layers NTN modifies.

Pick a sub-topic — the ones with › open their own interactive deep-dive:

gNB functional split — CU-CP · CU-UP · DU · RU; F1 & E1 interfaces
Why the CU/DU split shaped the NTN payload debate (resolved to full-gNB regenerative in Rel-19)
NR air interface — numerology / SCS, frame & slot structure, BWP, SSB & beamforming
Protocol stack — PHY · MAC · RLC · PDCP · SDAP · RRC, the layers NTN modifies

1.4

Introduction to Non-Terrestrial Networks

Why NTN exists, the platform families, and the link/segment vocabulary used for the rest of the week.

The coverage gap terrestrial networks cannot close — oceans, deserts, aviation, disaster zones
NTN platforms — GEO / MEO / LEO satellites, HAPS and airborne nodes
Service link vs. feeder link — the NTN gateway & ground segment
Direct-to-device vs. very-small-aperture / fixed terminals
NTN as 5G-Advanced — a first-class part of Rel-18/19 and a building block for 6G

1.5

3GPP NTN Standardization Roadmap

NTN is fully standardized — the same NR/5GC protocols are adapted for the satellite link, not replaced. Every capability anchors to a release.

The release timeline — Study → Rel-17 → Rel-18 → Rel-19 → 6G, each release clickable to its work items & specs
What NTN changes, layer by layer — PHY · MAC · RLC · PDCP · RRC · NAS and the exact spec each lives in
The NTN spec map — every 3GPP specification NTN touches, grouped by working group
Transparent → regenerative — the payload debate, resolved to full-gNB-on-satellite in Rel-19
Bands & reference scenarios — n255/n256 (L/S), n510–512 (Ka) and TR 38.821 scenarios

3GPP NTN release map

Release	Status	Key NTN content
Study TR 38.811 / 38.821	Completed	NTN channel models, reference scenarios, deployment & link-budget templates
Rel-17	Frozen	First normative NR-NTN (FR1 / S-band) + IoT-NTN (NB-IoT / eMTC); transparent payload; GNSS-based TA, `K_offset`, `K_mac`, Doppler pre-comp, extended RACH / HARQ
Rel-18	Frozen	Coverage & mobility enhancements; TN↔NTN mobility; work toward FR2 (Ku/Ka); network-verified UE location
Rel-19	Frozen · Dec 2025	Regenerative payload = full gNB onboard; Store-and-Forward; RedCap over NTN; DL coverage + UL capacity (OCC); MBS service-area signalling; new NTN bands & NTN PWS
Rel-20 / 21	Ongoing	Rel-20: 6G studies (from 2025); Rel-21: first normative 6G specs with NTN integrated from the start

Certain for Rel-17/18; Rel-19 frozen Dec 2025; Rel-20/21 scope still evolving. Source: 3GPP NTN overview & Rel-19 summary.

LAB

Hands-on Lab 1 — 5G SA Core Baseline + UE Registration

Stand up a terrestrial 5G SA core and capture the call flow — this becomes the reference baseline every NTN comparison is measured against.

Hands-on Lab 1

5G SA Core Baseline + UE Registration

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1Deploy Open5GS 5G SA core; bring up a UERANSIM gNB and UE
2Perform UE registration and establish a PDU session
3Capture NAS, NGAP and PFCP messages in Wireshark
4Build the registration + PDU-session sequence diagram (terrestrial baseline for later NTN comparison)

Open5GSUERANSIMWireshark

Deliverable — an annotated call-flow used as the reference point throughout the course. Open the full lab guide →

QUIZ

Day 1 Assessment

Everything from Day 1 — the 5G SA baseline, SBA, the gNB split, the NTN “why”, platforms and the 3GPP roadmap. 61 spec-cited questions, graded instantly.