5G NTN Explained: LEO Satellites, HAPS & 3GPP R17 Architecture

The 5G NTN architecture explained end to end: how a LEO satellite delivers a 5G New Radio signal to an ordinary phone, and the three things 3GPP had to redesign to make it work. We cover the two Release 17 NTN payload architectures (transparent vs regenerative), the RAN adaptations for timing (extended Timing Advance, SIB19 ephemeris broadcast, GNSS self-compensation, K-offset), HARQ over long round trips (up to 32 processes and per-process feedback disabling with RLC Acknowledged Mode), the regenerative registration call flow (gNB-DU on board, gNB-CU and 5G core on the ground), and how HAPS compares to LEO and GEO. We finish with which enterprise use cases (maritime, aeronautical, rural private 5G backhaul) are feasible on Release 17 today versus Release 18. Chapters: 0:00 Introduction 0:48 Why NTN breaks the assumptions 1:45 Transparent vs Regenerative payload 3:05 Timing: extended TA, ephemeris & Doppler 4:27 HARQ over long round trips 5:52 Regenerative registration call flow 7:25 HAPS vs LEO vs GEO 8:38 Enterprise: Rel-17 vs Rel-18 10:00 Summary SignalLayer breaks down 5G and telecom architecture for engineers — accurate, no buzzwords. Subscribe for the next one: a full LEO satellite handover, step by step. #5G #NTN #Telecom Chapters: 0:00 Introduction 0:42 Why NTN breaks the assumptions 1:37 Transparent vs Regenerative payload 2:47 Timing: extended TA, ephemeris & Doppler 3:59 HARQ over long round trips 5:09 Regenerative registration call flow 6:23 HAPS vs LEO vs GEO 7:27 Enterprise: Rel-17 vs Rel-18 8:39 Summary