The document discusses non-terrestrial networks (NTN), focusing on various types of satellite orbits—geostationary (GEO), medium Earth orbit (MEO), and low Earth orbit (LEO)—and their impact on connectivity. It highlights the architecture of NTN including transparent and regenerative satellite-based networks, as well as potential applications such as continuous connectivity for transport systems and remote areas. References to 3GPP studies on NTN and the evolving requirements for 5G systems are also included.

1. Non-Terrestrial Networks
(NTN)
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2. Terrestrial and Non-Terrestrial Networks
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Terrestrial Networks
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3. Terrestrial and Non-Terrestrial Networks
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Aircraft
• Typically 9 to 11.5 kmTerrestrial Networks
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4. Terrestrial and Non-Terrestrial Networks
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Satellites
• GEO – 35,786 km
• MEO – 7,000 to 25,000 km
• LEO – 300 to 1,500 km
Aircraft
• Typically 9 to 11.5 kmTerrestrial Networks
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5. Summary of proposed LEO Constellations Designs
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Source: Semantic Scholar

6. Telesat vs SpaceX vs OneWeb
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Source: MIT

7. ©3G4G

8. How Satellite Connectivity Works
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Internet
Satellite Gateway
Or Earth Station
Satellite
Terrestrial Base Station
Earth Station
Communication Link
Mobile phones
Satellite phone

9. How Satellite Connectivity Works
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Internet
Satellite Gateway
Or Earth Station
Satellite
Terrestrial Base Station
Earth Station
Communication Link
Mobile phones
Satellite phone
Mobile Network Operator
Core Network / Data Center

10. Terrestrial and Non-Terrestrial Networks
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Satellites
• GEO – 35,786 km
• MEO – 7,000 to 25,000 km
• LEO – 300 to 1,500 km
UAS
• UAS Range – 8 to 50 km
• Typically 18 to 27 km
• HAPS – 20 km
Aircraft
• Typically 9 to 11.5 kmTerrestrial Networks
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UAS = Unmanned Aircraft System
HAPS = High-Altitude Platform Station

11. Different Types of HAPS and Altitudes
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Aeroplane
9 to 11.5 km
Google Loon
20 km
Unmanned drones
20 - 25 km
Aerostatic HAPS
20 km
HAPSMobile
20 km

12. ©3G4G
Source: 3GPP
3GPP TS 22.261 (Rel-15)
3GPP TR 22.822 (Rel-16)
3GPP TS 22.261 (Rel-16)

13. ©3G4G
Source: 3GPP

14. NTN Characterization [3GPP TR 38.821]
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Platforms Altitude range Orbit
Typical beam
footprint size
Low-Earth Orbit (LEO) satellite 300 – 1500 km
Circular around the earth
100 – 500 km
Medium-Earth Orbit (MEO)
satellite
7000 – 25000 km 100 – 500 km
Geostationary Earth Orbit
(GEO) satellite
35 786 km notional station keeping position fixed in
terms of elevation/azimuth with respect
to a given earth point
200 – 1000 km
UAS platform (including
HAPS)
8 – 50 km (20 km for HAPS) 5 - 200 km
High Elliptical Orbit (HEO)
satellite
400 – 50000 km Elliptical around the earth 200 – 1000 km
UAS - Unmanned Aircraft Systems
LTA - Lighter than Air UAS
HTA - Heavier than Air UAS

15. NTN Architectures
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1. Transparent-satellite based NG-RAN architecture,
2. Regenerative-satellite based NG-RAN architecture with gNB
on board, and
3. Regenerative-satellite based NG-RAN architecture with gNB-
DU on board.
3GPP TR 38.821: Solutions for NR to support non-terrestrial networks (NTN)

16. Evolving from single-node in 4G to split function architecture in 5G
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Source: ITU-T GSTR-TN5G Transport network support of IMT-2020/5G
UPUP
L1'L1'
RRU
BBU
EPC
S1
CPRI
CN
CU
DU
RRU
F1
NG
eCPRI/CPRI/
NGFI
L1",L2-RTL1",L2-RT
L2-NRT,L3L2-NRT,L3
UPUP
CPCP/UP
corecore
4G 5G
Xn
X2
BBU – BaseBand Unit
CU – Central Unit
DU – Distributed Unit
RRU – Remote Radio Unit

17. Mapping of CU and DU functions according to the split points
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CU – Central Unit
DU – Distributed Unit
RU – Remote Unit
RRH – Remote Radio Head
NGC – Next-generation Core

18. Transparent-satellite based NG-RAN architecture
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UE gNB
NR Uu NG N6
5G CN
Data
Network
NTN
Gateway
NG-RAN
Remote Radio Unit

19. Regenerative-satellite based NG-RAN architecture with gNB on
board
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UE
gNB
NR Uu
NG N6
5G CN
Data
Network
NTN
Gateway
NG-RAN
NG over SRI

20. Regenerative-satellite based NG-RAN architecture with gNB-DU
on board
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UE gNB-DU
NR Uu NG N6
5G CN
Data
Network
NTN
Gateway
NG-RAN
F1 over SRI
F1
gNB-CU

21. ©3G4G

22. Use-Cases and Applications
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• Continuity in connection over trains, boats, planes, etc.
• Connectivity for ships out in the ocean
• Service availability everywhere, especially for emergency
communications
• Connectivity for rural, remote, unserved and underserved areas
• Connectivity for M2M/IoT devices
• 3GPP TR 38.811, section 4.2 provides a lot more use cases for anyone
interested

23. 3GPP References
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• 3GPP TS 22.261: Service requirements for the 5G system;
Stage 1
• 3GPP TR 22.822: Study on using Satellite Access in 5G; Stage 1
• 3GPP TR 38.811: Study on New Radio (NR) to support non
terrestrial networks
• 3GPP TSG RAN meeting #83 RP-190710: Revised SID for Study
on solutions for NR to support non-terrestrial networks (NTN)
• 3GPP TR 38.821: Solutions for NR to support non-terrestrial
networks (NTN)
• 3GPP TS 38.401: NG-RAN; Architecture description

24. Thank You
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