**2. Concept of 5G satellite implementation**

The implementation of 5G satellite component for 5G service access on principles "at any time with any user in any place" helps to meet many challenges. However, there are numerous other hindrances requiring comprehensive and global studies.

Generally, the regions that are subject to coverage by terrestrial mobile networks of radio access are of fragmentary nature and correspond with the places of population concentration, regarding the economic expediency of base stations building. In some cases, the sparsely populated territories not covered by modern telecommunications. Thus, at the outset of 3G (IMT-2000) development, the universal coverage by mobile services was the key prerequisite for network construction, contributing to the formation of global 3G segment. However, in the course of 4G network evolution, the idea of global coverage by these networks was not even contemplated, in the hope of finding the convergent solutions in the field of satellite and terrestrial mobile telecommunications.

The concept of 5G satellite component considered nowadays rests upon the following preconditions [3]:


The requirements for 5G satellite component will be defined by, first of all, the aggregate of services carried out by 5G, consolidated in the families of usage scenarios of 5G terrestrial segment [4, 5]: enhanced Mobile Broadband (eMBB), Massive Machine-Type Communications (mMTC or mIoT), and Ultra-Reliable Low Latency Communication (URLLC).

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*Prospects of 5G Satellite Networks Development DOI: http://dx.doi.org/10.5772/intechopen.90943*

future.

other carrying vessels.

of radio coverage by terrestrial 5G networks.

and ensuring global access to content.

IoT devices with low power consumption.

The potential of satellite networks to uphold the key scenarios for 5G applications is specified by already existing characteristics applicable to modern satellite networks as well as tendencies in satellite technology development in future:

• *eMBB scenario*. According to this scenario, satellite networks are capable of maintaining data transfer at speed up to several gigabits per second, meeting the requirements for extended services of mobile broadband

• *mMTC scenario*. Satellite communication systems are already keeping up the technology of SCADA and other global applications for cargo and object tracking in the context of IoT devices mass use. Their capabilities can be scaled up to support devices and services of IoT within the direct control channel or as a feedback line with IoT and M2M devices from remote locations, ships, and

• *uRLLC scenario*. Satellite communication systems gained notoriety owing to its and their satellite communication systems gained notoriety by owing to its and their ability to meet the case concerning the requirements for network signal delays, aiming at procuring critical and highly reliable communications. The principal users of these networks are international broadcasters, mobile network operators, governmental bodies, and commercial users. The applications that turn out to be more sensitive to signal delays can be bolstered via new medium and low earth orbit satellite networks, which will to be deployed.

5G satellite networks are such networks, where radio access network NG-RAN is designed by means of satellite network utilization. Technical specifications of 3GPP

**Case 2.** Broadcast and multicast with a satellite overlay. In this case, the operator of 5G satellite network provides video broadcasting or any other delivery of services

within the global territory. The existing terrestrial mobile networks, supplying broadcasting services, can rely on 5G satellite network aiming at meeting its primary objectives related to the expansion of radio resource, broadcasting content,

**Case 3.** Internet of Things with a satellite network. In this case, 5G satellite network operator provides the delivery of IoT-services globally. Space segment of 5G satellite network uses low-orbiting satellites so as to ensure radio connections for

**Case 4.** Temporary use of a satellite component. In this case, a number of 5G network operators with access to the satellite component grant access to their

**Case 1.** Roaming between terrestrial and satellite networks. In this case, 5G satellite network operator provides data services delivery on globally coverage basis. An operator of terrestrial 5G network, in its turn, concludes roaming agreement with the operator of 5G satellite network operator as well as the other terrestrial network operators. User terminal exploits 5G satellite network only in the absence

[3] identified several cases for 5G satellite network use, presented below.

eMBB. Nowadays, satellite technologies can broadcast thousands of channels with the content of high bandwidth (HD and UHD). In its turn, this potential can be used to support the mobile network services of future generation. At present, satellites are being used as transport networks within 2G/3G in many regions of the world, whereas high-throughput satellites (HTS) of modern and future generations on geostationary and non-geostationary orbits can maintain transport infrastructure of mobile networks 4G/LTE and 5G in

*Moving Broadband Mobile Communications Forward - Intelligent Technologies for 5G…*

potential role of satellite subscriber's links in the 5G ecosystem.

**2. Concept of 5G satellite implementation**

studies.

mobile telecommunications.

following preconditions [3]:

services for all end-users.

Latency Communication (URLLC).

Additionally, the Working Group FM44 of ECC CEPT completed the preparation of ECC Report "Satellite Solutions for 5G" [2] that will determine the role of satellite component within 5G conception of in relation to the Regions, where services cannot be carried out in circumvention of satellites. In its turn, CEPT came forward with initiative to estimate the pros of satellites for 5G in terms of efficiency, capacity, and stability. Since CEPT Administrations are considering the issues related to 5G implementation in the nearest future, so the studies of satellite access in 5G are expected to facilitate the process of decision-making regarding the

The implementation of 5G satellite component for 5G service access on principles "at any time with any user in any place" helps to meet many challenges. However, there are numerous other hindrances requiring comprehensive and global

Generally, the regions that are subject to coverage by terrestrial mobile networks of radio access are of fragmentary nature and correspond with the places of population concentration, regarding the economic expediency of base stations building. In some cases, the sparsely populated territories not covered by modern telecommunications. Thus, at the outset of 3G (IMT-2000) development, the universal coverage by mobile services was the key prerequisite for network construction, contributing to the formation of global 3G segment. However, in the course of 4G network evolution, the idea of global coverage by these networks was not even contemplated, in the hope of finding the convergent solutions in the field of satellite and terrestrial

The concept of 5G satellite component considered nowadays rests upon the

• 5G satellite component is to be integrated into other mobile and fixed networks, but not as autonomy one for the provision of 5G services. The integration of satellite and terrestrial 5G segments forms the key aspect of this vision;

• Satellite communication systems are fundamental components for reliable delivering of mobile services, not only in Europe, but also in other regions of

• 5G satellite component will facilitate universality of 5G networks as well as the solution for various issues dealt with maintenance of multimedia traffic growth, global coverage, M2M, and critical telecommunications (emergency

• Satellite component may become a part of configuration for 5G hybrid network, consisted of combination of broadcasting and broadband infrastructures, run in a manner to ensure uninterrupted and online convergence of 5G

The requirements for 5G satellite component will be defined by, first of all, the aggregate of services carried out by 5G, consolidated in the families of usage scenarios of 5G terrestrial segment [4, 5]: enhanced Mobile Broadband (eMBB), Massive Machine-Type Communications (mMTC or mIoT), and Ultra-Reliable Low

the world as by continuum over time and at a reasonable price;

and natural disasters) in optimizing costs for end-users;

**84**

The potential of satellite networks to uphold the key scenarios for 5G applications is specified by already existing characteristics applicable to modern satellite networks as well as tendencies in satellite technology development in future:


5G satellite networks are such networks, where radio access network NG-RAN is designed by means of satellite network utilization. Technical specifications of 3GPP [3] identified several cases for 5G satellite network use, presented below.

**Case 1.** Roaming between terrestrial and satellite networks. In this case, 5G satellite network operator provides data services delivery on globally coverage basis. An operator of terrestrial 5G network, in its turn, concludes roaming agreement with the operator of 5G satellite network operator as well as the other terrestrial network operators. User terminal exploits 5G satellite network only in the absence of radio coverage by terrestrial 5G networks.

**Case 2.** Broadcast and multicast with a satellite overlay. In this case, the operator of 5G satellite network provides video broadcasting or any other delivery of services within the global territory. The existing terrestrial mobile networks, supplying broadcasting services, can rely on 5G satellite network aiming at meeting its primary objectives related to the expansion of radio resource, broadcasting content, and ensuring global access to content.

**Case 3.** Internet of Things with a satellite network. In this case, 5G satellite network operator provides the delivery of IoT-services globally. Space segment of 5G satellite network uses low-orbiting satellites so as to ensure radio connections for IoT devices with low power consumption.

**Case 4.** Temporary use of a satellite component. In this case, a number of 5G network operators with access to the satellite component grant access to their

network with a minimum set of service (such as voice, messaging, and mail) so as to provide to each user devices under the satellite coverage a guaranteed access.

**Case 5.** Optimal routing or steering over a satellite. The 5G networks will combine available terrestrial and satellite network components to optimize the connectivity of user devices in accordance with the requested QoS. Depending on the quality requirements to QoS-parameter 5QI as well as bandwidth, the optimal traffic routing is secured within the territories of joint radio coverage (of satellite and terrestrial networks). In a 5G network with satellite access, user devices with terrestrial access and supporting satellite networks access will be capable of dual connectivity with a satellite access network and a terrestrial access network. A 5G network with satellite access will be capable of establishing independently uplink and downlink connectivity through the 5G satellite and 5G terrestrial access networks.

**Case 6.** Satellite transboundary service continuity. This case provides for 5G global satellite network within the territory of a few countries. According to the prerequisites established by legislation of the relevant states, subscribers' traffic is to be terminated in user location, within the licensed network. Consequently, in compliance with this statement, 5G satellite network is being designed as access network to respective terrestrial networks, covering the territories of various states. Therefore, it can also be used as autonomous 5G network on neutral territories.

**Case 7.** Global satellite overlay. In this case, global low-orbiting satellite network will be utilized as the overlaying network of terrestrial data network. The topology of communication links will be defined on basis of minimizing delivery time of protocol data unit. Thus, the main idea considers that delay of signal propagation equals the speed of light (299,792,458 m/s) in airspace, whereas in optical fiber, this parameter achieves up to 2/3 of speed of light. Based on the above, time duration equals 1 ms correlates with propagation distance of 300 km in airspace and 200 km in optical fiber (excluding curvature of circuit). With more large distance between the source and recipient of a message (reaching several thousand km), the difference in time delivery may be significant and actually for a series of applications in banking, burs exchange, and industry fields.

**Case 8.** Indirect connection through a 5G satellite access network. This case will be assumed that mass user devices will be deprived access to satellite interface. Interaction of these 5G user devices with satellite networks is carried out through relay user units (Relay UE), supporting satellite interface. This relay UEs can function separately or will be set into rescue vessels, air planes, and railway carriages. While implementing these indirect connections of 5G user devices through satellite access networks, it is vital to solve the issues dealing with security, tariffing, etc.

**Case 9.** 5G fixed Backhaul between NR and the 5G core. This option considers the use of satellite network by organizations of transport channels Midhaul, Backhaul between stationary base stations gNB and 5G core network. The interfaces between the 5G core and NR are transported directly over the satellite link.

**Case 10.** 5G Moving platform Backhaul. This case considers the utilization of satellite network for transport link organizations in 5G network (Moving Platform) such as Midhaul, Backhaul between moving gNBs and 5G core network. Moving 5G base stations can be placed on river and maritime vessels, trains, etc.

**Case 11.** 5G to premises. This case implies that 5G satellite network interoperates with non-3GPP technologies (for instance, IEEE 802.11, IEEE 802.16). It is using a home/office gateway unit to combine the available signals from 5G satellite network and to present modern Wi-Fi coverage within the premises.

**Case 12.** Satellite connection of remote service center to off-shore wind farm. In this use, case 5G satellite network based on Low Earth Orbit (LEO) satellite used for set up satellite link connection with local control center in the wind power

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communications.

sion volume.

**Table 1.**

**orbits**

**Table 2.**

**Types of satellite** 

*UE to satellite propagation delay.*

different heights [6] is shown in **Table 1**.

**3. Spectrum aspects of 5G satellite segment use**

limits reach 30, 90, and 280 ms.

*Prospects of 5G Satellite Networks Development DOI: http://dx.doi.org/10.5772/intechopen.90943*

*Minimum satellites needed to maintain global radio coverage.*

plant communication network includes a 5G satellite user device. It will be provided low satellite communication latency and high uplink/down data transmis-

LEO 3 15 30 MEO 27 43 90 GEO 120 140 280

**Types of satellite orbits Height, km Number of satellites**

1400 ≈ 50

**Delays in link "User terminal-satellite", ms Maximum one-way delay, ms Minimum Maximum**

Low earth orbit (LEO) 800 ≈ 80

Medium earth orbit (MEO) 8000 ≈ 10 Geostationary earth orbit (GEO) 35,786 ≈ 3

However, these cases do not finish and limit possibility of 5G satellite segment applications and will be proceeded in 3GPP study in Release 17 on 5G evolution. The main flaw of satellite segment consists in increased delay of information transfer owning to distance between user units and gNB base station. The requirements submitted to the quality of service for data transfer within 5G satellite segment also depend on the relevant number of satellites in operation. The minimum quantity of satellites in operation needed to maintain radio coverage for orbits of

The signal delays forming for different satellite orbits and satellite limits on satellite segment delays are presented in **Table 2**. Additionally, the indicated delays are summarized with 5 ms delay, added by satellite. Therefore, maximum delay

Other QoS-requirements (Default Priority Level, Packet Delay Budget, Packet

On the one hand, spectrum and wide bandwidth for 5G terrestrial networks will require utilization of millimeter-wave (mm-wave) bands to provide data transfer speed reaching up to 20 Gigabits per second in 5G radio interface connect with the process of delivery of the extended broadband mobile access (eMBB) service. On other hand such requirements to use frequency channels with bandwidth from 50 up to 400 MHz for eMBB-services can provide only in mm-wave bands which already utilized within satellite networks. That is why mm-wave bands in nearest future will turn out to be the most requested in 5G and satellite

World Radiocommunication Conference 2019 (WRC-19) allocated of additional mm-wave frequency bands 24.25–27.5 GHz, 37–43.5 GHz, and 66–71 GHz for 5G

Error Rate) for 5G satellite segment have set in 3GPP technical specifications.

#### *Prospects of 5G Satellite Networks Development DOI: http://dx.doi.org/10.5772/intechopen.90943*


#### **Table 1.**

*Moving Broadband Mobile Communications Forward - Intelligent Technologies for 5G…*

provide to each user devices under the satellite coverage a guaranteed access. **Case 5.** Optimal routing or steering over a satellite. The 5G networks will combine available terrestrial and satellite network components to optimize the connectivity of user devices in accordance with the requested QoS. Depending on the quality requirements to QoS-parameter 5QI as well as bandwidth, the optimal traffic routing is secured within the territories of joint radio coverage (of satellite and terrestrial networks). In a 5G network with satellite access, user devices with terrestrial access and supporting satellite networks access will be capable of dual connectivity with a satellite access network and a terrestrial access network. A 5G network with satellite access will be capable of establishing independently uplink and downlink connectivity through the 5G satellite and 5G terrestrial access

network with a minimum set of service (such as voice, messaging, and mail) so as to

**Case 6.** Satellite transboundary service continuity. This case provides for 5G global satellite network within the territory of a few countries. According to the prerequisites established by legislation of the relevant states, subscribers' traffic is to be terminated in user location, within the licensed network. Consequently, in compliance with this statement, 5G satellite network is being designed as access network to respective terrestrial networks, covering the territories of various states. Therefore, it can also be used as autonomous 5G network on neutral territories.

**Case 7.** Global satellite overlay. In this case, global low-orbiting satellite network will be utilized as the overlaying network of terrestrial data network. The topology of communication links will be defined on basis of minimizing delivery time of protocol data unit. Thus, the main idea considers that delay of signal propagation equals the speed of light (299,792,458 m/s) in airspace, whereas in optical fiber, this parameter achieves up to 2/3 of speed of light. Based on the above, time duration equals 1 ms correlates with propagation distance of 300 km in airspace and 200 km in optical fiber (excluding curvature of circuit). With more large distance between the source and recipient of a message (reaching several thousand km), the difference in time delivery may be significant and actually for a series of applications in

**Case 8.** Indirect connection through a 5G satellite access network. This case will be assumed that mass user devices will be deprived access to satellite interface. Interaction of these 5G user devices with satellite networks is carried out through relay user units (Relay UE), supporting satellite interface. This relay UEs can function separately or will be set into rescue vessels, air planes, and railway carriages. While implementing these indirect connections of 5G user devices through satellite access networks, it is vital to solve the issues dealing with security, tariffing, etc. **Case 9.** 5G fixed Backhaul between NR and the 5G core. This option considers the use of satellite network by organizations of transport channels Midhaul, Backhaul between stationary base stations gNB and 5G core network. The interfaces

between the 5G core and NR are transported directly over the satellite link.

base stations can be placed on river and maritime vessels, trains, etc.

and to present modern Wi-Fi coverage within the premises.

**Case 10.** 5G Moving platform Backhaul. This case considers the utilization of satellite network for transport link organizations in 5G network (Moving Platform) such as Midhaul, Backhaul between moving gNBs and 5G core network. Moving 5G

**Case 11.** 5G to premises. This case implies that 5G satellite network interoperates with non-3GPP technologies (for instance, IEEE 802.11, IEEE 802.16). It is using a home/office gateway unit to combine the available signals from 5G satellite network

**Case 12.** Satellite connection of remote service center to off-shore wind farm. In this use, case 5G satellite network based on Low Earth Orbit (LEO) satellite used for set up satellite link connection with local control center in the wind power

banking, burs exchange, and industry fields.

**86**

networks.

*Minimum satellites needed to maintain global radio coverage.*


#### **Table 2.**

*UE to satellite propagation delay.*

plant communication network includes a 5G satellite user device. It will be provided low satellite communication latency and high uplink/down data transmission volume.

However, these cases do not finish and limit possibility of 5G satellite segment applications and will be proceeded in 3GPP study in Release 17 on 5G evolution.

The main flaw of satellite segment consists in increased delay of information transfer owning to distance between user units and gNB base station. The requirements submitted to the quality of service for data transfer within 5G satellite segment also depend on the relevant number of satellites in operation. The minimum quantity of satellites in operation needed to maintain radio coverage for orbits of different heights [6] is shown in **Table 1**.

The signal delays forming for different satellite orbits and satellite limits on satellite segment delays are presented in **Table 2**. Additionally, the indicated delays are summarized with 5 ms delay, added by satellite. Therefore, maximum delay limits reach 30, 90, and 280 ms.

Other QoS-requirements (Default Priority Level, Packet Delay Budget, Packet Error Rate) for 5G satellite segment have set in 3GPP technical specifications.
