Content for TR 38.811 Word version: 15.4.0
2 References
3 Definitions, symbols and abbreviations
4 Non-Terrestrial Networks Overview - background information
5 Non-Terrestrial Networks deployment scenarios
6 Non-Terrestrial Networks channel models
7 Potential key impact areas on NR to support NTN
8 Recommendations on the way forward
A Example of reference scenario for calibration of large scale parameters
B Non Terrestrial network characteristics
$ Change history
2 References
3 Definitions, symbols and abbreviations Word‑p. 10
4 Non-Terrestrial Networks Overview - background information Word‑p. 13
4.1 Roles for Non-Terrestrial Networks in 5G system
4.2 5G Use Cases wherein Non-Terrestrial Network components have a role
4.3 Satellite and aerial access network architecture principles Word‑p. 17
4.4 Characteristics of NTN Terminals for satellite / aerial access network Word‑p. 20
4.5 Air/Space borne vehicle characteristics Word‑p. 21
4.6 Coverage pattern of NTN
4.7 Non-Terrestrial Network architecture options Word‑p. 22
4.8 Spectrum Word‑p. 23
5 Non-Terrestrial Networks deployment scenarios Word‑p. 24
5.1 Scenarios overview
5.2 Attributes Word‑p. 25
5.3 Doppler and Propagation delay characterisation Word‑p. 26
5.3.1 Methodology
5.3.2 Geo-stationary platforms Word‑p. 27
5.3.3 Aerial vehicle Word‑p. 32
5.3.4 Non geostationary satellites Word‑p. 33
5.3.4.1 Propagation delay
5.3.4.2 Differential delay Word‑p. 34
5.3.4.3 Doppler Shift and variation rate
5.3.4.3.1 Case at 2 GHz Word‑p. 36
5.3.4.3.2 Case in Ka band Word‑p. 37
5.3.4.4 Doppler Shift and variation rate Word‑p. 41
5.3.5 Synthesis for each scenarios Word‑p. 42
6 Non-Terrestrial Networks channel models Word‑p. 43
6.1 Status/expectation of existing information for satellite/HAPS channels
6.1.1 Channel modeling works outside of 3GPP
6.1.2 Targeted user environment
6.1.3 Modeling objectives
6.2 Differences between satellite/HAPS and cellular channel modelling
6.3 Coordinate system Word‑p. 45
6.4 Antenna modelling
6.5 Methodology to define channel models
6.6 Large scale model Word‑p. 48
6.6.1 LOS probability
6.6.2 Path loss and Shadow fading
6.6.3 O2I penetration loss Word‑p. 50
6.6.4 Atmospheric absorption Word‑p. 51
6.6.5 Rain and cloud attenuation Word‑p. 52
6.6.6 Scintillation
6.7 Fast fading model Word‑p. 58
6.8 Additional modelling components Word‑p. 86
6.9 Channel models for link level simulations Word‑p. 88
6.9.1 CDL models
6.9.2 TDL models Word‑p. 91
6.10 Channel model calibration Word‑p. 94
7 Potential key impact areas on NR to support NTN Word‑p. 96
7.1 Specific constraints associated to NTN
7.2 NR features/protocols potentially affected Word‑p. 98
7.3 NR modifications to support the Non-Terrestrial Network deployment scenarios Word‑p. 101
7.3.1 Methodology
7.3.2 Motion of the space/aerial vehicles
7.3.2.1 Hand-Over and paging
7.3.2.1.1 Problem statement
7.3.2.1.2 Assessment of conditions for NR operation in Non-Terrestrial networks Word‑p. 102
7.3.2.1.3 NR impact considerations
7.3.2.2 TA adjustment
7.3.2.2.1 Problem statement
7.3.2.2.2 Assessment of conditions for NR operation in Non-Terrestrial networks Word‑p. 103
7.3.2.2.3 NR impact considerations Word‑p. 104
7.3.2.3 Initial synchronization in downlink
7.3.2.3.1 Problem statement
7.3.2.3.2 Assessment of conditions for NR operation in Non-Terrestrial networks
7.3.2.3.3 NR impact considerations
7.3.2.4 DMRS time density Word‑p. 105
7.3.3 Altitude of the space/aerial vehicles
7.3.3.1 HARQ
7.3.3.1.1 Problem statement Word‑p. 107
7.3.3.1.2 Assessment of conditions for NR operation in non-terrestrial networks Word‑p. 108
7.3.3.1.3 NR impact considerations
7.3.3.2 MAC/RLC procedures
7.3.3.2.1 Problem statement
7.3.3.2.2 Assessment of conditions for NR operation in Non-Terrestrial networks
7.3.3.2.3 NR impact considerations Word‑p. 109
7.3.3.3 Physical layer procedures (ACM, power control)
7.3.4 Cell size (Beam foot print)
7.3.4.1 PRACH and Random access
7.3.4.1.1 Problem statement
7.3.4.1.2 Assessment of conditions for NR operation in Non-Terrestrial networks Word‑p. 110
7.3.4.1.3 NR impact considerations Word‑p. 111
7.3.4.2 TA in Random access response message
7.3.5 Propagation channel
7.3.5.1 DMRS frequency density
7.3.5.1.1 Problem statement
7.3.5.1.2 Assessment of conditions for NR operation in Non-Terrestrial networks Word‑p. 113
7.3.5.1.3 NR impact considerations
7.3.5.2 Cyclic prefix
7.3.6 Duplex mode
7.3.7 Satellite or aerial Payload performance
7.3.7.1 PT-RS
7.3.7.1.1 Problem statement
7.3.7.1.2 Assessment of conditions for NR operation in Non-Terrestrial networks
7.3.7.1.3 NR impact considerations Word‑p. 116
7.3.7.2 PAPR
7.3.8 Network architecture
8 Recommendations on the way forward Word‑p. 122
8.1 General outcomes
8.2 Reference deployment scenarios
8.3 Non-Terrestrial network channel modelling
8.4 NR impacts to support Non-Terrestrial networks
A Example of reference scenario for calibration of large scale parameters Word‑p. 125
B Non Terrestrial network characteristics Word‑p. 126
$ Change history Word‑p. 127
