Date of publication xxxx 00, 0000, date of current version xxxx 00, 0000.
10.1109/ACCESS.2017.DOI

This work was supported by ESA in the frameworks of the ESA Project “Satellite
Communications via Space-Based Internet Service Providers” and the Luxembourg
National Research Fund (FNR) in the frameworks of the FNR-CORE Project
“MegaLEO: Self-Organised Lower Earth Orbit Mega-Constellations” under Grant
C20/IS/14767486/MegaLeo.

Corresponding author: Houcine Chougrani (e-mail: houcine.chougrani@uni.lu).

# Connecting Space Missions From NGSO Constellations: Feasibility Study

HOUCINE CHOUGRANI1  OLTJON KODHELI2  ALI GEORGANAKI1  JAN THOEMEL1  CHIARA
VITTORIA TURTORO2  FRANK ZEPPENFELDT3  PETROS PISSIAS3  MAHULENA HOFMANN2  AND
SYMEON CHATZINOTAS1  Interdisciplinary Centre for Security, Reliability and
Trust (SnT), University of Luxembourg, L-1855 Luxembourg, Luxembourg (e-mail:
houcine.chougrani, ali.georganaki, jan.thoemel, mahulena.hofmann,
<EMAIL_ADDRESS> Société Européenne des Satellites, SES S.A.,
Betzdolf, Luxembourg. (e-mail: oltjon.Kodheli,
<EMAIL_ADDRESS> European Space Agency (ESA). (e-mail:
frank.zeppenfeldt<EMAIL_ADDRESS>
###### Abstract

A space-based internet system (e.g., Starlink, OneWeb, o3b mPower), despite
possessing the capability to provide internet services to on-ground users in a
global scale, can dramatically change the way space missions are designed and
operated in the foreseeable future. Assuming a scenario where space mission
satellites can access the internet via a space internet system, the satellite
can be connected to the network permanently (24x7) and act as mere terminal
independently from its location. The ability to communicate with the satellite
on-demand has the potential to improve aspects such as real-time tasking,
outage minimization, operation cost, and dependency on the ground. This paper
performs a feasibility study on the concept of connecting space missions using
space-based internet systems. This study includes a review of existing and
near-future space internet systems, identification of candidate space missions
for the proposed concept, a necessary adaptation of existing Commercial off-
the-shelf (COTS) terminals to be plugged into space mission satellites,
assessment of communication performance, and investigation of the legal
aspects of the radio frequency (RF) spectrum usage. The paper evidences that
the concept is practically possible to implement in the near future. Among the
studied space internet systems (i.e. Starlink, OneWeb, o3b mPower), O3b mPower
stands out as the best system allowing permanent coverage of low earth orbit
(LEO) space missions with data rates that can reach up to 21 Mbps per
satellite. Although the concept is very promising and can be implemented in
near future, our investigations show that some regulation aspects regarding
the RF usage should be solved for future deployment.

###### Index Terms:

space-based internet system, space mission, Starlink, OneWeb, o3b mPower, LEO,
RF, Legal Aspects.

=-15pt

##  I Introduction

Nowdays the number of satellites launched into low earth orbit (LEO), usually
for data-gathering missions such as Earth Observation (EO) and remote sensing,
is constantly increasing [1]. Their satellite operators heavily depend on a
ground station, or a network of ground stations, placed at strategic locations
to obtain data from these space mission satellites (or send data/command to
the satellite). This results in a limited link availability of about once link
occasion per orbit (near polar sun-synchronous orbit with polar ground-station
or near-equatorial orbit with equatorial ground station) to few per day (near
polar orbit with low and mid-latitude ground-station) [2]. Increasing the
number of ground stations for the purpose of expanding the communication
opportunities with the satellite would drastically escalate the cost of a
particular LEO mission. With the advent of a new type of space-based internet
providers (e.g. SpaceX, OneWeb, Amazon) [3], communications with space
missions satellites can potentially be revolutionized. Thus the paradigm of
relying on ground stations at strategic Geo-locations to downlink data from
LEO satellites a few times per day can be challenged. Assuming a scenario
where LEO satellites (e.g. space missions) can access the internet via a
space-based internet system (SBIS), satellites can potentially be connected to
the network permanently (24/7). Data can be available on demand, regardless of
the satellites positions. This has the potential to change dramatically the
way satellites will be operated. This includes the possibility of the
satellite itself initiating an asynchronous (spontaneous) link to the ground
(e.g., in case of contingency), and real-time tasking (e.g., collision
avoidance, tt&C, data offloading, etc).

Currently, only a limited number of space-to-space connectivity solutions
exist. In the geostationary (GEO) orbit category, the Inter-Satellite Data
Relay System (IDRS) is a solution launched by Inmarsat and Addvalue, which is
capable of providing on-demand 24/7 connectivity to LEO satellites in all
orbital inclinations and at altitudes of up to 1000 km [4]. The data rates
supported by their services are 200 - 300 kbps. In the same category, we have
also the National Aeronautics and Space Administration (NASA) Tracking and
Data Relay Satellite (TDRS) [5] and European Data Relay Satellite (EDRS) [6].
In the LEO category, Kepler Inc.’s satellites are a system that aims to
provide real-time communications to other satellites, space stations, launch
vehicles, habitats, and any other space-borne assets in the near future [7].
With their new terminals specifically designed for space, the data rate
supported by the Kepler system is between 10 - 40 kbps.

While the range of data rates provided by the above-mentioned systems might be
enough for certain applications (e.g. telecommand and control operations), it
is insufficient for others where higher throughput is required. Most
importantly, the proposed concept in this paper does not require any specific
link to connect space missions but the idea herein is to leverage the already
existing link for ground users to connect the space missions (see Fig. 1).
From a SBIS perspective, this requires few modifications111Modifications on
the communication protocol might be needed to deal with the high relative
motion of space mission satellites to their existing system, and space
missions, in this context, are seen as mere terminals. This concept was
proposed first time in our previous work in [8], where preliminary analyses
were done. In this paper, a deeper analysis is done considering the technology
needed on space mission satellites, communication link performance as well as
legal aspects related to Radio frequency (RF) usage.

Figure 1: Connecting space missions from space-based internet system

The scope of this work is to focus on existing and near-future systems aiming
to offer high-speed broadband services to on-ground users and perform a
feasibility study on using the same system to connect space missions. The main
contributions of this paper are summarized as follows:

  1. 1.

A survey of the main current and near-future SBIS with their features,
services as well as their orbital characteristics.

  2. 2.

Identification of the space mission categories that may take advantage of the
proposed concept.

  3. 3.

Investigation of the necessary technologies on-board the space mission-
satellite, including the review of existing technologies and identification of
potential ones to be integrated into a LEO user-satellite.

  4. 4.

Assessment of communication performance, including coverage analysis to
quantify the effective visibility time to establish a communication link, link
budget evaluation, and performance analysis for a hypothetical system composed
of the selected space mission and most promised SBIS.

  5. 5.

Investigation of legal aspects of the RF spectrum usage. This includes the
examination of the current spectrum usage policy vis-a-vis the proposed
concept, necessary conditions for compliance with the regulatory framework,
and recommendations to make the concept viable.

The content of the paper is organized as follows. Section II describes the
system elements including space missions and SBIS with their features; Section
III, presents the results of the feasibility study of the proposed concept;
Section IV is dedicated to spectrum usage policy investigation; finally,
Section V provides the conclusions of this work.

##  II System elements

###  II-A Space missions

To understand the added value of SBIS to space missions, we performed a review
of past, ongoing, and future space missions. We constrain our research to
space missions in low Earth orbit because SBIS satellites are residing in
low/medium Earth orbit and feature nadir beams.

TABLE I: Summary missions benefiting from space-based internet provision and valuation per benefit Mission category\ Potential advantage | high throughput (1-3) | link availability (1-3) | low latency (1-3) | Sum
---|---|---|---|---
Human space flight | 3 | 3 | 3 | 9
Experimental/In-Orbit Demonstration (IOD) missions | 1 | 1 | 1 | 3
Earth Observation mission | 3 | 3 | 1 | 7
Other scientific missions | 1 | 1 | 1 | 3

Based on their objectives, we categorized these space missions into four
types, and discussed their relevance to connect with SBIS:

  * •

Human space flight currently only consists of the International Space Station
(ISS)[9] and the Chinese space station Tianhe [10]. It is however expected
that private space stations will be launched in the future.
The needs of such missions are (1) high throughput due to the production of
large amounts of telemetry and science data, (2) low latency connectivity for
voice and video applications, and (3) long-duration or permanent connectivity
for safety monitoring.

  * •

Experimental missions, such as most CubeSat missions and others that serve in-
orbit demonstration (IOD) purposes. These kind of missions are very diverse
and typically do not have particular communication needs. They may benefit
however from low-cost connectivity.

  * •

EO missions, acquire data for the characterization of the Earth’s surface and
atmosphere and hence produce a large amount of data. These missions are
primarily in LEO due to the benefits of the proximity to the observation
target with few exceptions in higher orbits. Some of those missions address
exploratory fundamental science purposes[11]. Their data is processed over
years after the data acquisition. Other EO missions are of operational nature
serving the monitoring of the atmosphere’s chemical composition[12, 13]. Those
need to transfer their data to users with a short delay.

  * •

Scientific missions are typically conducted by space agencies for the
scientific community. Examples include missions for astronomical observations.
They typically acquire large amounts of data and hence need high-throughput
links, but such missions have typically no stringent data availability and
latency needs. Thus, they can downlink data upon opportunity such as an
available ground station link.

Based on the analysis of space mission communication needs, we estimate that
the main potential advantages of connecting space missions to SBIS are large
data amount transfer (from space mission to space-based internet provider
satellite) and long duration or even permanent connectivity features. However,
some missions would benefit from low-latency and low-cost connectivity.

The advantages per mission category are summarized in table I. We have omitted
to list the potential advantages of low-cost connectivity as, at the time of
writing, the price for such services is unknown. Table I shows that Human
space flight and EO missions are the best fit for the proposed concept. Given
the abundance of EO missions, their overwhelming need for broadband data rate,
and the rarity of human space flight missions, we concluded that the first
user of SBIS connectivity is likely EO missions. Hence, we select NASA’s past
mission Aqua and ESA’s future mission BIOMASS as a reference for the remainder
of the study. Their main features are given in Table II.

TABLE II: Size, Mass, Power characteristics of reference missions. | NASA Aqua | ESA BIOMASS
---|---|---
orbit | SSO 1:30 LTAN, 700 km | SSO 6 am/pm, 660 km
size [m3] | 40 | 20
mass [kg] | 3,000 | 1,200
power [W] | 5,000 | 1,500

###  II-B Space-based internet systems

In this section, we describe the main technical peculiarities of current and
near-future SBIS that are relevant to the proposed concept. In the LEO
category, we investigate four of the largest mega-constellations currently
providing, or envisioned to provide broadband services, namely Telesat,
OneWeb, Starlink, and Kuiper. In the MEO category, we consider O3b mPower. We
did not consider the GEO category, even though it is also a candidate for the
proposed concept222The GEO systems might provide good performance but their
main weaknesses are the absence of coverage in the polar regions and higher
latencies compared to NGSO solutions. Table II-B1 summarizes the space
internet provider’s constellation parameters.

####  II-B1 Starlink

On November 2020 SpaceX announced its testing phase of offering internet
services, termed as “better than nothing (beta)” [14]. According to the latest
reports, the testing phase ended in October 2021 [15], and the broadband
services offered by Starlink are available nationwide, although still limited
by the peak number of users [16]. As stated in their latest Federal
Communications Commission (FCC) filings approved on April 2021 [17], Starlink
mega-constellation will be mainly composed of 4408 satellites placed in five
orbital shells. The first shell has already been deployed and constitutes the
initial phase. It contains 72 orbital planes with 22 satellites each at 550 km
altitude and 53∘ inclination. The second phase involves the deployment of the
4 other orbital shells; one with 72 orbital planes at 53.2∘ inclination
containing 22 satellites each at 540 km altitude, one with 36 orbital planes
at 70∘ inclination containing 20 satellites each at 570 km altitude, one with
6 orbital planes at 97.6∘ inclination containing 58 satellites each at 560 km
altitude, and one with 4 orbital planes at 97.6∘ inclination containing 43
satellites at 560 km altitude. Finally, Starlink constellation is operating
with a minimum elevation angle of 25∘.

TABLE III: Space internet provider’s constellation parameters

SBIPs |  No. of sat. |  Altitude (km) |  Planes |  Sat. per plane |  Incl. (∘) |  Min. Elev. (∘)
---|---|---|---|---|---|---
Starlink |  4408 |  540 |  72 |  22 |  53.2 |  25
|  550 |  72 |  22 |  53 |
|  560 |  6 |  58 |  97.6 |
|  560 |  4 |  43 |  97.6 |
|  570 |  36 |  20 |  70 |
OneWeb |  6372 |  1200 |  36 |  49 |  87.9 |  25
|  |  32 |  72 |  55 |
|  |  32 |  72 |  40 |
Telesat |  1671 |  1015 |  27 |  13 |  98.98 |  10
|  1325 |  40 |  33 |  50.88 |
Kuiper |  7774 |  590 |  56 |  28 |  33 |  20
|  610 |  72 |  36 |  42 |
|  630 |  68 |  34 |  51.9 |
|  640 |  652 |  1 |  72 |
|  650 |  325 |  2 |  80 |
O3b  mPower |  60 |  8062 |  1 |  44 |  0 |  5
|  |  2 |  8 |  70 |

####  II-B2 Oneweb

According to the FCC filings [18, 19, 20], OneWeb’s system mainly consists of
two phases. Phase 1 was initiated on April 2016 [18], when OneWeb requested
the authorization to operate 720 non-geostationary (NGSO) satellites at a 1200
km altitude. On May 2020, a modification for the Phase 1 was requested,
reducing the number of satellites from 720 to 716, and modifying the orbital
planes of some of the satellites in the constellation [19]. More specifically,
the initial phase consists of two sets of orbital planes; 12 planes with
inclination 87.9∘, and 8 planes with inclination 55∘. The high-inclined planes
will contain 49 satellites per plane, while the low-inclined ones will contain
16 satellites. In order to reach global coverage, on January 2021, Oneweb
requested to FCC the authorization to operate 6372 satellites for its Phase 2
[20]. The second phase intends to drastically increase the number of
satellites in the constellation by increasing the number of the already
existing planes in Phase 1. Particularly, the high-inclined planes are
increased from 12 to 36, while the low-inclined ones are expanded to 32
containing 72 satellites per plane (from 16 satellites in Phase 1). In
addition, a third set of orbital planes is added with 40∘ inclination,
consisting of 32 planes with 72 satellites each. Similar to Starlin, the
OneWeb minimum elevation for the service link is 25∘.

####  II-B3 Telesat

As described in their FCC filings [21, 22], Telesat’s system will consist of
298 satellites in the initial phase, and reach 1671 satellites in the final
phase. Ka-band frequencies will be utilized for both, user and gateway (GW)
links, and the final constellation will operate with a minimum elevation angle
of 10 degrees. Two types of orbits will be used, high-inclined or polar orbits
with inclination 98.98∘ and altitude 1015 km, and low-inclined orbits with
inclination 50.88∘ and altitude 1325 km. In the first phase, there will be 6
high-inclined planes containing 13 satellites each and 20 low-inclined planes
with 11 satellites per plane. In the second phase, the number of polar planes
will be increased to 27, while the number of the low-inclined ones will
double. In addition, the number of satellites contained in each of the orbital
planes with inclination 50.88∘ will increase from 11 to 33 satellites.

####  II-B4 Kuiper

Kuiper is the newest mega-constellation system announced by Amazon in 2019 to
offer broadband services. In their initial FCC filings which has already been
approved, it has been requested to build a system containing 3236 satellites
[23] with 20∘ as minimum elevation angle for both service and GW links. The
satellites will be distributed in three orbital shells; one with 28 orbital
planes at 33∘ inclination containing 28 satellites each at 590 km altitude,
one with 36 orbital planes at 42∘ inclination containing 36 satellites each at
610 km altitude, and another one with 34 orbital planes at 51.9∘ inclination
containing 34 satellites each at 630 km altitude. Recently, on November 2021,
a new request has been submitted to FCC to launch another 4538 satellites,
expanding the number of satellites to 7774 [24]. The orbital planes mentioned
above will be simply doubled, thus doubling the number of satellites with the
same orbital configurations. Also, two orbital shells are introduced, one with
652 orbital planes at 72∘ inclination containing 1 satellite each at 640 km
altitude, and another one with 325 orbital planes at 80∘ inclination
containing 2 satellites each at 650 km altitude.

####  II-B5 O3b mPOWER

O3b mPOWER is the future satellite constellation in Medium Earth orbit (MEO)
owned and operated by SES [25]. The O3b mPower system target markets as cruise
ships, off-shore energy, cloud-scale IP networks, Intelligence-Surveillance-
Reconnaissance, enterprise-level organizations, mobile backhaul, commercial
shipping, government network solutions, commercial aero, and generic cloud
services [26]. According to their FCC filings [27], the final constellation
will consist of two orbital planes with a 70∘ inclination containing 8
satellites each and 44 satellites in the equatorial plane with a minimum
elevation angle of 5∘. According to [28], the O3b mPOWER constellation will
consist initially of 11 powerful satellites, each equipped with more than
5,000 digitally formed beams, and an extensive next-generation O3b mPOWER
ground infrastructure. Note that the first two O3b mPOWER satellites were
successfully launched in December 2022. It is worth noting here that SES has
currently an O3b constellation composed of 20 satellites, orbiting in an
equatorial plane. This constellation is not O3b mPOWER but can be seen as a
first generation of it.

##  III System feasibility analysis

###  III-A Space user terminal

To aid the research for the use of SBIS, an investigation is carried out to
determine the necessary technologies on-board the user-satellite (i.e. space
mission). A system engineering approach is adopted. A review of existing
technologies is carried out helping to understand their potential and
compatibility with the proposed concept. Then a buy-make-modify decision is
made. In this context, NASA conducted a study on the use of broadband
satellite provider [29] concluding that no terminals are immediately available
for the use on their missions. Currently, Thinkom advertises a development
regarding their terminal use on satellites on their website [30]. GetSat
states informally that no activities are planned in this regard due to the
limited market size.

Terrestrial solutions exist to connect to broadband provider satellites in
geostationary, mid-altitude and low-altitude orbits. They are:

  * •

Very commonly available commercial products

  * •

Have a very high maturity as the products are delivered as turnkey solutions
to private and governmental customers

  * •

Are designed for on-the-move applications (e.g. boats, planes and helicopters)
and under harsh environments

  * •

Provide high reliability uses such as for combat

Commercial off-the-shelf (COTS) terminals are fully integrated and can often
be used without major set up. The user has the choice to use the integrated
modem and its Transmission Control Protocol/Internet Protocol (TCP/IP)
interface or alternatively an Open Antenna to Modem Interface Protocol
(OpenAMIP) [31] interface to control the antenna. The latter has emerged as an
industry standard for such applications.

In particular, we have considered for this study: (1) GetSat’s mechanically
steerable antennas (MSA) of the Nanosat, Millisat and Microsat series, (2)
GetSat’s electronically steerable antennas (ESA) of the Sling Blade series,
(3) Kymeta’s u8 terminal and (4) Thinkom’s Thinpack series with hybrid
steerable antennas (HSA). All the relevant terminals are summarized in Table
IV with their key features.

TABLE IV: Available COTS terminals and their key features Product [freq. band] |  Max. EIRP [dbW] |  G/T [dB/K] |  Elev. |  link acquisition [s] |  Steering method |  Mass [kg] |  Size [cm]
---|---|---|---|---|---|---|---
Nighingale I [ka] [32] |  30 |  n/a |  30-90 |  n/a |  ESA |  1.2 |  12 x 8.3 x 1
Nanosat [Ka] [33] |  39.7 |  2.2 |  0-90 |  $<$ 30 |  MSA |  2.3 |  19.5 x 16
Microsat LW [Ku] [34] |  42.7 |  4.2 |  0-90 |  $<$ 30 |  MSA |  4 |  29 x 21
Microsat LW [Ka] [34] |  46.3 |  8.2 |  0-90 |  $<$ 30 |  MSA |  3.2 |  29 x 21
Millisat W LW [Ku] [35] |  46.1 |  7.2 |  -8-90 |  $<$ 30 |  MSA |  17.7 |  57.5 x 27
Millisat W LW [Ka] [35] |  49 |  11.2 |  -8-90 |  $<$ 30 |  MSA |  17.3 |  57.5 x 27
Sling Blade LM milli [Ku] [36] |  46.5 |  11.5 |  10-90 |  $<$ 30 |  ESA |  48 |  66 x 9 x 90.9
Micro Sling Blade LM milli [Ka] [34] |  49 |  10.5 |  10-90 |  $<$ 30 |  ESA |  18.7 |  60 x 7 x 56
u8 GEO [Ku] [37] |  45.5 |  11.5 |  15-90 |  n/a |  ESA |  32 |  90 x 90 x 12
ThinPack100 [ku] [38] |  40 |  11.5 |  n/a |  n/a |  Hybrid |  2.7 |  40 x 25 x 6
ThinPack100 [ka] [38] |  46 |  13 |  n/a |  n/a |  Hybrid |  4.2 |  41 x 28 x 5

The suitability of broadband terminals for LEO space mission satellites has
been assessed against three main criteria: (1) communication function, that
is, the interface to the host satellite and to the mega-constellation space-
based internet providers, (2) space and launch environment, and (3) satellite
system engineering resources availability.

####  III-A1 Communication function

Terrestrial terminals are typically highly integrated and feature all
necessary functions to establish a link to a broadband satellite providers.
Such functions include:

  * •

Fast steering of the antenna (either MSA, ESA or HSA). This is made possible
due to location awareness, thanks to an integrated global navigation satellite
systems (GNSS) system, the stored ephemerides of provider satellites in
combination with an inertial measurement unit (IMU), and the received signal
strength indicator (RSSI) tracking method.

  * •

Use of standard interfaces such as point-to-point TCP/IP through ethernet from
integrated modem, and OpenAMIP.

  * •

Power amplifier/block-up-converter

  * •

Commonly used frequency bands such as Ku and Ka-bands

  * •

Cold and hot start connection capability as well as hand-over between
satellites or providers.

The communication function is hence mature and requires no major engineering
for its use on LEO satellites.

####  III-A2 Space and launch environment

Terrestrial terminals are typically semi-rugged or fully-rugged designed for
terrestrial outside or terrestrial harsh environments. The compatibility with
satellite mechanical design driving mechanical loads, such as launch
vibrational loads, cannot finally be verified due to the unavailability of the
design information, which is kept as a commercial secret. However, the use-
case of the terminal for on-the-move applications on boats, trains, planes,
and helicopters implies a high mechanical resilience. The steering mechanism
of the MSA is sensitive to launch loads; inherently, ESAs are less sensitive
due to the absence of mechanisms.

Specifications of the investigated terminals show the use of polycarbonate and
other plastic for protection against rain, contact, and pollution. For space-
use, such covering plastics is prohibitive and, in most cases, not necessary.
Further plastic use may be made inside the terminals. Antennas are
maintenance-free implying encapsulated lubrication of mechanisms. Yet, a
detailed review-of-design of material used needs to be conducted to assess the
compatibility to LEO vacuum and atomic oxygen environment. This will likely
result in the removal of plastic materials and possibly a redesign of
mechanisms.

The terminals dissipate a significant amount of heat. To this end, typically
fans are foreseen to enhance advective cooling, which is not feasible in
space. For use in the vacuum of space, a careful thermal management and
cooling concept needs to be designed allowing removing excess heat. It needs
function to transport heat away from the terminal and the host satellite and
radiate heat into space. We estimate that heat conduction with metal
conductors or heat pipes and classical radiators suffice this purpose.

The compatibility to the host-satellite-emitted electromagnetic interference
(EMI, conducted or radiated) is currently unknown. However, the COTS
terminals’ current use-case scenario is generic and hence indicates a robust
EMI design. The terminal-radiated EMI, however, is likely significant due to
the large emitted RF power levels. Furthermore, the current use-case (i.e.,
on-ground use) may be agnostic to radiation lobes at the back surface, which
may not be the case for on-satellite use. Hence, a detailed analysis test and
possibly a mitigation design are needed.

Finally, regarding the space radiation effects, the broadband use-cases
necessitate an orbit at the lower end of LEO altitudes and hence at the lower
end of the van Allen belt where the otherwise dominating trapped proton and
electron radiation is low. Hence, the effect of radiation on terminal
electronics might be low. However, the susceptibility to space radiation
requires dedicated analysis. Experience shows that many COTS systems suffice
this benign radiation environment [39].

####  III-A3 Satellite system engineering resources availability

From the main satellite system engineering characteristics of space missions,
we can derive what resources would be available for the broadband
communication subsystem. Those are:

  * •

Surface magnitude availability (zenith): 1 m2 order of magnitude

  * •

Electrical power magnitude availability: hundreds of Watts (orbit average)

  * •

zenith-surface mounted terminal should have permanent zenith visibility.

The last item deserve attention: whereas SBIS-satellites are in view of the
user-satellite’s zenith surface for extended duration, the SBIS beam is
typically not - due to its relatively small beamwidth, which can be seen in
Fig. 1. Hence, the ”effective” visibility where the communication can be
established will depend on the SBIS’s beams and constellation characteristics
(e.g., number of satellites, altitude). Section III-B will be dedicated to
evaluate the effective visibility time.

Besides, frequent switches from one SBIS satellite to another are necessary.
This advocates the use of ESA, which can switch with shorter delay from one
SBIS-satellite to another or employ several beams simultaneously.
Alternatively, the use of more than one MSA terminal can reduce link
unavailability: while one antenna maintains a link, the second can prepare and
establish a link to the next provider satellite. However, the use of two
terminals on the zenith surface is limited. The size of the terminals
investigated here prohibits the use of two terminals on the space mission
satellites.

####  III-A4 Suggested delta design

The investigated terminals have a high functional maturity and well-defined
and proven interfaces. From this point of view, they appear ready for
integration into a LEO space mission satellite. Functional verification would
suffice. Their consumption of system engineering resources (size, surface,
mass, power) is well within what relatively small satellites can provide.
However, commercial products are not designed for the space environment. From
our analysis, the main design challenge appears to be the thermal management.
Commercial terminals rely on advective and fan-enhanced cooling, which is
unavailable and infeasible in space. A space-grade thermal management system
consisting of heat transport and heat rejection components needs to be added.
Materials used may not be compatible with the LEO environment. A detailed
design review is needed, and all non-space grade materials need to be removed
or replaced. The harsh launch vibrational environment may be detrimental to
these commercial products. A review-of-design followed by a shaker-test
verification is needed. Possibly, the structure and mechanical interfaces need
reinforcements.

From the above analysis, we can conclude that COTS terminals have a great
potential to be used on LEO broadband user missions. Their overall maturity
allows their integration into satellites after the delta design work on the
thermal management and other detailed review-of-design verification has been
carried out. Also, a standard system engineering design activity has to be
carried out for the intended mission. Among the two major categories of
terminals (i.e. MSA and ESA), MSA should be discarded.

From the considered terminals, the GetSat’s Sling Blade and Thinkom’s
ThinPack100 stand out as good candidates for space mission satellites.

###  III-B Coverage analysis

In this sub-section, we perform the coverage analysis for various SBISs using
the System Tool Kit (STK) Software. Two main metrics have been evaluated, the
coverage time from the constellation, and the coverage time from each
individual satellite. We select three SBISs for the evaluation, Starlink,
OneWeb, and O3b mPower. The coverage of the other SBISs (e.g. Kuiper, Telesat)
can be concluded by analogy, since their orbits are similar to either Starlink
or Oneweb. In this analysis, we assume the same space segment characteristics
of the SBIS (i.e. steering capabilities of the satellite antenna) which are
derived based on the minimum elevation angle that SBIS systems can reach on
the ground.

Figure 2: Starlink partial constellation (in green) and VLEO space mission (in
white).

Regarding the space missions, as highlighted in section II-A, we have selected
Aqua and Biomass missions for the coverage analysis (shown in dark blue and
pink in Fig. 3 and Fig. 4). It is worth highlighting here that for Starlink
the range of satellite altitudes is lower than the altitude of the selected
space missions (i.e. Aqua and Biomass). Therefore, Starlink constellation
might be suitable only for future missions in the very-LEO (VLEO) category
where the range of altitudes can be from 200 km – 500 km [40]. Therefore, the
analysis for Starlink is done by taking into account a hypothetical futuristic
VLEO mission at 300 km altitude and sun-synchronous orbit (shown in white
color in Fig. 2).

####  III-B1 Constellations modelling

Starlink and Oneweb are composed of a large number of satellites, 4408 and
6372, respectively. Therefore, in order to get results in a reasonable amount
of time, we have selected only a partial constellation, 407 for Starlink shown
in Fig. 2, and 428 satellites for OneWeb shown in Fig. 3. In addition, we make
sure that the selected satellites are, as much as possible, uniformly
distributed around the Earth to cover all possible regions and not target
specific ones. By doing that, we try to consider the most useful satellite
from a coverage point of view with the purpose of obtaining meaningful results
as close as possible to the ones that would have been obtained by utilizing
the full constellation.

Figure 3: OneWeb partial constellation (in light blue) and Aqua/Biomass space
mission (in dark blue and pink).

Unlike Starlink and OneWeb, the full O3b mPower constellation is modeled since
it has a total of only 60 satellites (see Fig. 4).

####  III-B2 Access duration

We analyzed the access and outage duration from each constellation to the
relevant space mission for one day. The results are given in Fig. II-B1.

Figure 4: O3b mPower full constellation (in green, red and yellow) and
Aqua/Biomass space mission (in dark blue and pink).

First, for Starlink, as can be noticed in Fig. 4a, many interruptions (i.e.
outages) occur and the access durations are short. For OneWeb, the situation
is better with fewer interruptions and longer access durations (see Fig. 4b),
while for O3b mPower the coverage is permanent and no interruption is observed
as shown in Fig. 4c. These results are expected since the coverage duration is
proportional to the difference in altitude between space mission satellites
and SBIS ones. This can be seen as a cone (see Fig. 1) where its apex is the
SBIS’s altitude and its base is the coverage for the space mission. Hence,
assuming a constant angle, the greater the height the larger the base (i.e.
coverage).

(a) Access and outage intervals for VLEO-300 km space mission to Starlink (b)
Access and outage intervals for Aqua space mission to OneWeb (c) Access and
outage intervals for O3b mPower to Aqua/Biomass space mission

Figure 5: Access and outage intervals for links between considered space
missions and SBIS constellations.

Table V quantifies these results in terms of numbers. The table provides the
total duration of access from space missions to the constellation together
with the minimum and maximum coverage duration without interruptions.

TABLE V: Access intervals from space missions to SBIS constellations SIPs |  Space mission |  Min. access duration w/o interruption [s] |  Max. access duration w/o interruption [s] |  Total access duration [s]
---|---|---|---|---
Starlink |  VLEO-300 km |  1.23 |  111.25 |  4638.11 (5.37%)
OneWeb |  Biomass |  302.01 |  15306.43 |  66764.44 (77.27%)
|  Aqua |  259.99 |  8295.61 |  65477.18 (75.78%)
O3b mPower |  Biomass |  86400 |  86400 |  86400 (100%)
|  Aqua |  86400 |  86400 |  86400 (100%)

For Starlink, the total access duration is only 77 min per day (i.e. 5.37% per
day) with 1.23 s and 1.8 min as minimum and maximum coverage duration without
interruption, respectively. Unsurprisingly, OneWeb’s total access duration is
much better reaching 18.5 hours a day (i.e. 77.27%) for Biomass and 18 hours
(i.e. 75.78%) for Aqua, with a minimum and maximum coverage duration without
interruption of 5 min and 4.3 hours, respectively. O3b mPower is the best
system with a permanent connection to space missions.

Before concluding on the coverage results, it is worth noting here that
another important metric, which is the percentage of satellites that provide a
certain coverage duration, should be analyzed. This is because certain access
periods are useless from a communication perspective since they are too short
to establish a communication link or to perform the handover procedure when
the link is already established. Of course, the required time either for the
access phase or handover depends on the communication system and the adopted
protocol. For example, it is evident that Starlink’s minimum access duration
of 1.23 s is not enough to establish communication but we wanted to emphasize
that the other access durations without interruption, including the maximum
ones, might be not fully exploited because it represents the access time from
the constellation (i.e. a set of satellites) and not per satellite. For
example, suppose a constellation has 100 side-by-side satellites with 2 s
access per satellite which results in 200 s coverage time which appears to be
good. However, the time per satellite is too short to be exploited for
communication, and the good time coverage of the constellation is useless in
this example. This is why it is important to assess the time coverage per
satellite in the constellation to conclude the useful coverage time.

To assess the above metric, we provide in Fig. 6 the empirical cumulative
distribution function (eCDF) of the access duration per satellite, for each
SBIS constellation. Now, assuming that the required time to establish a
communication is 20 s. For Starlink, this means that space users would not be
able to obtain connectivity 80% of the time there is a coverage (see Fig. 6).
In other words, given 77 min of total access time, only 15 min per day is
useful for communication. For OneWeb, only 1% of the total access time is not
useful representing around 11 min in the worst case. Finally, o3b mPower is
not impacted by the threshold, which means that all satellites in the
constellation have enough time to guarantee communication.

Figure 6: eCDF of the access duration per satellite for each SBIS
constellation.

###  III-C Link budget and data rate performance

We provide in this sub-section an evaluation of the link budget and assessment
of the performance for a hypothetical system composed of the selected Aqua
space missions and o3b mPower system. First, we provide the parameters of o3b
mPower and space mission in Table VI. The space mission payload parameters are
derived from section III-A. Parameters of two user terminals are considered
here, the NanoSat and ThinPack100 terminals. The former represents the case of
a low-performance terminal while the latter represents a high-performance one.
We performed this choice to get lower and higher bound performance. The
parameters of o3b mPower are derived from the FCC filling in [27].

TABLE VI: System parameters for numerical link budget evaluation. Parameters |  O3b mPower | Space mission
---|---|---
|  |  NanoSat |  ThinPack100
Satellite altitude |  8062 km |  700 km |  700 km
Downlink transmission
Frequency | Ka-band (i.e. 20 GHz)
Bandwidth | 100 MHz
EIRP |  49.7 dBW | NA
G/T |  NA |  2.2 dB/K |  13 dB/K
Uplink transmisson
Frequency | Ka-band (i.e. 30 GHz)
Bandwidth | 4 MHz
EIRP |  NA |  36.4 dBW |  46 dBW
G/T |  7 dB/K | NA

Fig. II-B1 provides the link budget results for both uplink (UL, space mission
to SBIS link) and downlink (DL, SBIS to space mission link) transmissions. The
obtained signal-to-noise ratio (SNR) differs depending on the space mission
payload characteristics (see Fig. 6a and 6c). As it can be noted, the obtained
SNR is better in the DL compared to the UL. This is mainly due to the higher
effective isotropic radiated power (EIRP) of the SBIS’s satellite compared to
the space mission one. Also, the SNR is time-variant due to the time-varying
distance between the space mission satellite and SBIS one. The maximum
achievable SNR in the UL (resp. DL) is about 14.5 dB (resp. 18 dB) for
Ka100-like payload, while for the NanoSat-like payload, it is about 5.5 dB
(resp. 7.5 dB). On the other hand, the minimum SNR in the UL (resp. DL) is
about 8 dB (resp. 11.5) for Ka100-like payload and -1 dB (resp. 1 dB) for
NanoSat-like payload. Since multi-users are competing for the UL resources,
the SNR of the latter will be variable depending on the scheduled resources
(i.e. bandwidth) from the provider.

In order to quantify the achievable data rate, we assume here a digital video
broadcasting second generation standard (DVB-s2x) protocol which is the most
probable protocol used by o3b mPwer system [41]. Therefore, the data rate is
obtained based on the DVB-s2x spectral efficiency [42] and the obtained SNRs.
Note that we take into account the DVB-s2x adaptive modulation and coding
mechanism for our data rate estimation.

The results are depicted in Fig. II-B1. For the DL, the achievable data rate
is very high. It ranges from 165 Mbps to 270 Mbps for Ka100-like payload, and
50 Mbps to 118 Mbps for nanosat-like payload. For the UL, which is the most
important link in our context333Space mission mainly download data acquired
during the mission, the achievable data rate ranges from 11 Mbps to 21 Mbps
for Ka100-like payload and 3.2 Mbps to 8.8 Mbps for NanoSat-like payload. The
obtained data rates are sufficient for many applications (e.g. video, data
sharing) and can be compliant with space missions requirements. Note that the
most important fact here is that these data rates can be permanently available
and therefore real-time data exchange and tasking can be available for the
connected space missions.

(a) DL (i.e., o3b mPower-to-Aqua) link budget

(b) Achivable DL data rate

(c) UL (i.e., Aqua-to-o3b mPower) link budget (d) Achievable UL data rate

Figure 7: Link budget and link performance when connecting Aqua space mission
to o3b mPower considering DVB-S2X protocol

##  IV Spectrum usage policy and legal consequences

In order to understand the feasibility from a regulatory perspective of the
envisaged space-based internet connectivity, it is necessary to examine the
current spectrum usage policy. In fact, to grant interference-free operations
the spectrum is divided into bands by the International Telecommunication
Union (“ITU”) and allocated to specific services [43], subject to regular
revision by the World Radiocommunication Conference (“WRC”) [44]. For the
purpose of this study, we have based ourselves on the following assumptions,
which are to be considered the most likely scenario to occur:

  * •

the constellation has been notified at the ITU as a “service” by the competent
Administration (“ADMIN 1”) and the constellation provider has been licensed to
provide services;

  * •

the space mission has been notified at the ITU by a different Administration
(“ADMIN 2”) which has licensed the relevant space mission to be operated via
the constellation;

  * •

the constellation provider and the space mission operator operate their
satellites respectively from the country of ADMIN 1 and country of ADMIN 2.

At this point, to establish communication between the space-based internet
provider and the space mission, the system should use frequency filings from
either the inter-satellite link or space-to-space allocation. While the former
is covered under the framework of the Inter-Satellite Services, the latter
allows to establish a satellite-to-satellite link where there is an allocation
in the space-to-space direction within the allocated frequencies for other
satellite services, e.g. Fixed Satellite Services (“FSS”) or Mobile Satellite
Services (“MSS”) [45].

We observed that the constellation systems under investigation in this study
neither rely on inter-satellite link frequencies nor can resort to space-to-
space transmissions within the allocated frequencies for the satellite
services they rely on444This is based on the fact that in Ka and Ku bands at
the moment there are no space-to-space transmissions. It derives that at the
state of the art, these systems could only file for an assignment under
Article 4.4 of the Radio Regulations (“RR”) 555Article 4.4 RR:
”Administrations of the Member States shall not assign to a station any
frequency in derogation of either the Table Frequency Allocations in this
Chapter or the other provisions of these Regulations, except on the express
condition that such a station, when using such a frequency assignment, shall
not cause harmful interference to, and shall not claim protection from harmful
interference caused by, a station operating in accordance with the provisions
of the Constitution, the Convention and these Regulations”. The latter is an
assignment not in accordance with the Table of Frequency Allocations [45] and
Article 11.31 RR, a so-called “non-conforming assignment”. These assignments
do not enjoy the right to international recognition and must be operated on
non-interference and non-protection bases. Moreover, assignments under Art.
4.4 impose additional obligations on the notifying administrations and
national legislations may, to a different extent, discourage or prohibit non-
conforming assignments [46]. This means that satellite operators wishing to
use non-conforming assignments are likely to encounter problems to be licensed
at the national level [47]. It becomes clear that recourse to Article 4.4
assignments is likely to have an impact on the actual exploitation of the
service and might act as a deterrent for the envisioned operations.

The situation just described might change according to the results of WRC-23
and the possible revision of the frequency allocations. More specifically,
Agenda Item 1.17, set out by Resolution 773 (WRC-19), has attributed Working
Party 4A the responsibility to determine the appropriate regulatory actions
necessary for the provision of satellite-to-satellite links in specific
frequency bands and to identify additional inter-satellite service allocations
[48]. Consequently, two possibilities might come to reality during WRC-23. We
noted how the impact on the feasibility of space-based internet connectivity
would be different if, on the one side, changes in WRC-23 would lead to (a)
the allocation of Ka and Ku bands to the Inter-Satellite Services or, on the
other hand, (b) the addition of space-to-space transmissions within allocated
frequency bands. In the case (a) above, the legal challenges stemming from an
assignment under Article 4.4 RR would be either removed or at least mitigated,
depending on whether Inter-Satellite Services are included as primary or
secondary services in Ka and Ku bands666Frequency bands can be allocated to
shared bands. Services in these shared bands can be divided into primary
services or secondary services. Primary services enjoy superior rights than
secondary ones. As a consequence, the latter shall neither cause harmful
interference to nor claim protection from the former. [49]. At the time of
writing, the developments regarding Agenda Item 1.17 suggest that case (b) is
the most probable outcome of WRC-23, with the introduction of space-to-space
transmissions within the allocated frequency bands of the FSS. The main
difference from the case (a) is that the satellite-to-satellite link must
operate within a stricter regime in terms of requirements. Operational
limitations derive from the “within the cone” concept of operations, meaning
operations that must comply with the area of space already covered by the
satellite filing under the FSS [49]. This means that if the constellation
defines a specific cone as service area in its filing, the establishment of a
satellite-to-satellite link between the constellation and the space mission
under the FSS frequency band allocation cannot result in novel geometries that
would extend the service beyond the declared service area. Consequently, we
concluded that these changes should be implemented by WRC-23, the
constellation, and the space mission shall comply with the following
requirements:

  * •

the constellation shall use the FSS frequency bands allocations;

  * •

the satellite-to-satellite transmissions between the space mission and the
constellation shall take place within the cone of coverage of the
constellation;

  * •

the space mission shall be at a lower orbital position than the constellation;

  * •

the transmissions shall respect the directionality indicators as in the
existing FSS allocations (Earth-to-space and space-to-Earth).

Based on the analysis of the spectrum policy relevant to the proposed concept,
we concluded that the current ITU regime applicable for the establishment of a
satellite-to-satellite link between the constellation and the space mission
(Article 4.4 RR assignments) is deemed not suitable for the provision of
space-based internet connectivity. The lack of international recognition
increases the risk of harmful interference with other operators with
conforming assignments and therefore might impede or severely prejudice the
actual use of these frequencies for satellite-to-satellite communication. For
example, it might expose the space mission to sudden cuts or interruptions of
the internet services provision, losing the advantage of a permanent/near
permanent connection. In fact, the opportunistic access to the frequency
spectrum is unreliable for commercial and public uses and therefore severely
limits the feasibility of these operations [47]. At the same time, the
revision of the RR during WRC-23 as described above might constitute a turning
point in the actual implementation of satellite communication via space-based
internet service providers. In such a hypothesis, there would be an adequate
legal protection and better premises for a continuous and efficient
exploitation of space-based internet services. This would constitute a huge
step forward in the provision of space-based internet services to space
missions.

##  V Conclusion

This paper evidences that the connection of space missions via space internet
providers is beneficial and most importantly is practically possible in the
near future. It was found that the most probable candidate that can take
advantage of the proposed concept is Earth observation missions because of (1)
their overwhelming need to transfer large amounts of data, (2) their need to
transfer data quickly, (3) their orbital compatibility with mega-
constellations (i.e. their low orbits) and (4) their abundant mass of users.
Our investigation showed that commercially available terminals have a great
potential to be used on LEO space mission spacecraft. Their overall maturity
allows their integration into satellites after the delta design work on the
thermal management and other detailed review-of-design verification has been
carried out. It turned out that O3b mPower is the best system for the proposed
concept followed by OneWeb, thanks to their relatively high altitude. The
evaluation showed that the link budget is favorable for performing
communication links between O3b mPower and space missions reaching up to 21
Mbps data rate in the UL considered as the most critical link. As per the
legal aspects, the study focused on the current legal regime at the ITU for
the establishment of the satellite-to-satellite link, and the necessary
conditions for compliance with the regulatory framework. It was found that at
the state of the art, the systems under investigation could only rely on a
flexible use of the spectrum allowed on a non-interference and non-protection
basis, the so-called Article 4.4 assignments. The lack of international
protection jeopardizes the operations at issue. This commercial and
operational disadvantage could be bridged by the possible changes to the table
of Frequency Allocations during the 2023 World Radiocommunication Conference.

## References

  * [1] Euroconsult, “New satellite market forecast anticipates 1,700 satellites to be launched on average per year by 2030 as new entrants and incumbents increase their investment in space.” [Online]. Available: https://www.euroconsult-ec.com/press-release/new-satellite-market-forecast-anticipates-1700-satellites-to-be-launched-on-average-per-year-by-2030-as-new-entrants-and-incumbents-increase-their-investment-in-space/
  * [2] D. Vrancken, D. Gerrits, J. Tallineau, J. Van Hove, P. Holsters, J. Naudet, S. Ilsen, L. Dayers, A. Keereman, D. Wierinck, T. Debraekeleer, D. Fussen, E. Dekemper, D. Pieroux, F. Vanhellemont, N. Mateshvili, G. Franssens, J. Vanhamel, B. Van Opstal, E. Neefs, J. Maes, L. Aballea, K. De Geeter, and L. De Vos, “ALTIUS: High performance Limb Tracker, based on a PROBA platform,” in _Proceedings of the International Astronautical Congress, IAC_ , vol. 5, 2014, pp. 3677–3688.
  * [3] H. Al-Hraishawi, H. Chougrani, S. Kisseleff, E. Lagunas, and S. Chatzinotas, “A survey on nongeostationary satellite systems: The communication perspective,” _IEEE Communications Surveys & Tutorials_, vol. 25, no. 1, pp. 101–132, 2023.
  * [4] Addvalue. World’s first on-demand real time connection for any leo satellite. [Online]. Available: https://www.idrsspace.com/what-we-do/connect
  * [5] NASA. Tracking and data relay satellite (tdrs). [Online]. Available: https://www.nasa.gov/directorates/heo/scan/services/networks/tdrs{_}main
  * [6] ESA. European data relay satellite system (edrs) overview. [Online]. Available: https://artes.esa.int/european-data-relay-satellite-system-edrs-overview
  * [7] Kepler. Kepler is building the internet in space. [Online]. Available: https://kepler.space/aether/
  * [8] H. Al-Hraishawi, M. Minardi, H. Chougrani, O. Kodheli, J. F. M. Montoya, and S. Chatzinotas, “Multi-layer space information networks: Access design and softwarization,” _IEEE Access_ , vol. 9, pp. 158 587–158 598, 2021.
  * [9] A. Thirkettle, B. Patti, P. Mitschdoerfer, R. Kledzik, E. Gargioli, and D. Brondolo, “Iss: Columbus,” _ESA Bulletin(0376-4265)_ , no. 109, pp. 27–33, 2002.
  * [10] S. Mallapaty _et al._ , “China’s space station is preparing to host 1000 scientific experiments,” _Nature_ , vol. 596, no. 7870, pp. 20–21, 2021.
  * [11] M. Berger, Y. Kerr, J. Font, J.-P. Wigneron, J.-C. Calvet, K. Saleh, E. López-Baeza, L. Simmonds, P. Ferrazzoli, B. van den Hurk _et al._ , “Measuring the moisture in the earth’s soil-advancing the science with esa’s smos mission,” _ESA bulletin_ , vol. 115, pp. 40–45, 2003.
  * [12] D. Fussen, N. Baker, J. Debosscher, E. Dekemper, P. Demoulin, Q. Errera, G. Franssens, N. Mateshvili, N. Pereira, D. Pieroux _et al._ , “The altius atmospheric limb sounder,” _Journal of Quantitative Spectroscopy and Radiative Transfer_ , vol. 238, p. 106542, 2019.
  * [13] J. Thoemel, N. Mateshvili, P. Demoulin, F. Vanhellemont, D. Pieroux, C. Bingen, E. Dekemper, G. Franssens, C. Robert, and D. Fussen, “On the accuracy of the sgp4 to predict stellar occultation events using envisat/gomos data and recommendations for the altius mission,” _CEAS Space Journal_ , vol. 11, no. 2, pp. 147–159, 2019.
  * [14] SpaceNews. Spacex opens starlink satellite internet to public beta testers: report. [Online]. Available: https://www.space.com/spacex-invites-starlink-internet-beta-testing
  * [15] Teslarati. Starlink exits its beta phase, but its production is affected by the global chip shortage. [Online]. Available: https://www.teslarati.com/starlink-exits-beta-production-chip-shortage/
  * [16] T. Boris. Elon musk: Spacex starlink internet to roll out nationwide this month! what to expect. [Online]. Available: https://www.techtimes.com/articles/266381/20211008/elon-musk-spacex-starlink-internet-roll-out-starlink-internet-roll-out-spacex-starlink-internet-elon-musk.htm
  * [17] FCC. ”spacex non-geostationary satellite system - attachment a - technical information to supplement schedule s”. [Online]. Available: https://fcc.report/IBFS/SAT-MOD-20200417-00037/2274316
  * [18] ——. Oneweb non-geostationary satellite system - attachment a - technical information to supplement schedule s. [Online]. Available: "https://fcc.report/IBFS/SAT-LOI-20160428-00041/1134939"
  * [19] ——. ”oneweb non-geostationary satellite system (leo) - phase 2: Modification to authorized system - attachment b - technical information to supplement schedule s”. [Online]. Available: "https://fcc.report/IBFS/SAT-MPL-20200526-00062/2379706"
  * [20] ——. ”oneweb non-geostationary satellite system (leo) - phase 2: Amended modification to authorized system - attachment b - technical information to supplement schedule s”. [Online]. Available: "https://fcc.report/IBFS/SAT-MPL-20210112-00007/3493913"
  * [21] ——, “Telesat canada requests u.s. market access for its planned ngso low earth orbit constellation,” 2016. [Online]. Available: https://fcc.report/IBFS/SAT-PDR-20161115-00108/1158531
  * [22] ——, “Telesat canada requests modification of its authorization to provide us market access from its ngso low earth orbit constellation,” 2020. [Online]. Available: https://fcc.report/IBFS/SAT-MPL-20200526-00053/2378320
  * [23] ——, “Kuiper systems llc requests authority to launch and operate a non-geostationary satellite orbit system using ka-band frequencies,” 2019. [Online]. Available: https://fcc.report/IBFS/SAT-LOA-20190704-00057/1773885
  * [24] ——, “Kuiper systems llc requests authority to launch and operate a non-geostationary satellite orbit system using v-band and ku-band frequencies,” 2021. [Online]. Available: https://fcc.report/IBFS/SAT-LOA-20211104-00145/13337528
  * [25] SES. O3b meo - proven high-performance connectivity. [Online]. Available: https://www.ses.com/our-coverage/o3b-meo
  * [26] ——. O3b mpower - redefining satellite services - connectivity is power. [Online]. Available: https://www.ses.com/o3b-mpower
  * [27] FCC, “O3b limited submits this further amendment to its pending application to modify its grant of u.s. market access for the o3b ka-band nongeostationary satellite system. the amendment seeks authority to serve the u.s. market using v-band frequencies,” 2016. [Online]. Available: https://fcc.report/IBFS/SAT-AMD-20170301-00026/1200241
  * [28] SES. First two o3b mpower satellites successfully launched. [Online]. Available: https://www.ses.com/press-release/first-two-o3b-mpower-satellites-successfully-launched
  * [29] B. Kul, P. Vrotsos, and E. Naffah, “Commercial communication services for nasa space missions: Capability assessment, opportunities and challenges,” 2020. [Online]. Available: {https://www1.grc.nasa.gov/wp-content/uploads/Ka-Band-Conference-Commercial-Communication-Services-for-NASA-Space-Missions.pdf}
  * [30] Thinkom, “Thinkom.” [Online]. Available: https://www.thinkom.com/satellite-payload-antennas/
  * [31] “OpenAMIP Standard Information Website.” [Online]. Available: https://www.idirect.net/products/openamip/
  * [32] CESIUM. Nightingale 1 ka-band communications system. [Online]. Available: {https://www.cesiumastro.com/systems/nightingale1#features-ng1}
  * [33] GETSAT. NANO SAT Ultra-portable SATCOM terminal. [Online]. Available: {https://www.getsat.com/products/nano/#product{_}downloads}
  * [34] ——. Micro sat lw portable on the move satcom terminal. [Online]. Available: https://www.getsat.com/products/micro-sat-lw/
  * [35] ——. Milli sat w lm fully ruggedized satcom terminal. [Online]. Available: {https://www.getsat.com/products/w-lm/#product{_}tech{_}specs}
  * [36] ——. Sling blade ku lm low profile electronically steerable antenna ku band. [Online]. Available: https://www.getsat.com/products/sling-blade-ku-lm/
  * [37] KYMETA. u8 geo terminal specifications. [Online]. Available: {https://www.groundcontrol.com/us/wp-content/uploads/sites/4/2022/02/Kymeta{_}U8{_}Flat-Panel{_}Brochure.pdf}
  * [38] ThinKom. Thinpack high-performance portable satcom antennas. [Online]. Available: {https://www.thinkom.com/wp-content/uploads/2022/03/thinpack-datasheet{_}thinkom.pdf}
  * [39] D. Sinclair and J. Dyer, “Radiation Effects and COTS Parts in SmallSats,” _27th Annual AIAA/USU Conference on Small Satellites_ , p. 2, 2013.
  * [40] J. V. Llop, P. Roberts, Z. Hao, L. R. Tomas, and V. Beauplet, “Very low earth orbit mission concepts for earth observation: Benefits and challenges,” in _Reinventing Space Conference_ , 2014, pp. 18–21.
  * [41] A. K. Rao, “O3b mPOWER A NEW ERA for Satellite Communications,” 2022.
  * [42] E. Standard, “Digital video broadcasting (dvb): Second generation framing structure, channel coding and modulation systems for broadcasting, interactive services, news gathering and other broadband satellite applications; part 2: Dvb-s2 extensions (dvb-s2x),” 2014.
  * [43] G. A. Codding Jr, “The international telecommunications union: 130 years of telecommunications regulation,” _Denv. J. Int’l L. & Pol’y_, vol. 23, p. 501, 1994.
  * [44] “World Radiocommunication Conferences (WRC).” [Online]. Available: https://www.itu.int/en/ITU-R/conferences/wrc/Pages/default.aspx
  * [45] ITU. Radio regulations. [Online]. Available: https://www.itu.int/pub/R-REG-RR-2020
  * [46] ——. Rules of procedure. [Online]. Available: https://www.itu.int/pub/R-REG-ROP-2021
  * [47] M. El-Moghazi, J. Whalley, and J. Irvine, “The future of international radio regulations: Transformation towards sharing,” 2017.
  * [48] R. . W.-. ITU, “Study of technical and operational issues and regulatory provisions for satellite-to-satellite links in the frequency bands 11.7-12.7 ghz, 18.1-18.6 ghz, 18.8-20.2 ghz and 27.5-30 ghz,” 2019. [Online]. Available: {https://www.itu.int/dms{_}pub/itu-r/oth/0C/0A/R0C0A00000F00169PDFE.pdf}
  * [49] I.-R. S. Groups, “Wrc-23 agenda item 1.17 resolution 773 (wrc-19),” 2022.

|  Houcine Chougrani is a Research Scientist at the SnT, University of
Luxembourg. He obtained the State Engineering degree in electronics from École
Nationale Polytechnique Algiers, Algeria, in 2011, the M.S. degree in signal
processing from Paul Sabatier University, Toulouse, France, in 2012, and his
Ph.D. degree in information technology from École Telecom Bretagne, Brest,
France, in 2016 From 2017 to 2018, he was a Research and Development Engineer
at the Department of Telecommunication, Airbus Defence and Space. From 2018 to
2019, he was a Research and Development Engineer at OQ Technology. His
research interests include the development and implementation of advanced
techniques for both terrestrial and satellite communication focusing on the
3GPP-based protocols
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|  Oltjon Kodheli is a Payload Engineer at SES, Luxembourg. He received the
master’s degree (cum laude) in electronic engineering from the University of
Bologna, Italy, in 2016, and the Ph.D. degree in telecommunication engineering
from the University of Luxembourg, in 2021. From 2021 to 2022, he was a
Research Associate at the SnT, University of Luxembourg. His research
interests include PHY and MAC layer design for wireless communication systems,
with a particular focus on 3GPP-based Non-Terrestrial Networks.
---|---
|  Ali Georganaki is a Doctoral Researcher in Information Technologies at SnT,
University of Luxembourg. He obtained his M.Sc degree in Telecommunications
Engineering (summa cum laude) from Alma Mater Studiorum Università di Bologna,
Italy 2022. He has been diversely schooled and has practiced Aerospace
Engineering (M.Sc) and Electrical Engineering (B.Sc) in multiple institutes
since 2014, namely École Nationale de l’Aviation Civil (ENAC) in Toulouse,
France, and Aerospace Research Institute. Ali’s research and design interests
incorporate non-terrestrial systems, and he currently explores AI manipulation
to assist satellite communication and space connectivity for the 6G era. He
finds great value in joining forces of art and science.
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|  Jan Thoemel is a Research Scientist and Head of the CubeSatLab at the SnT
within the University of Luxembourg. He obtained his PhD at the von Karman
Institute, Belgium, and the RWTH Aachen in hypersonics. He managed for the
European Space Agency the payload of the EXPERT reentry capsule before
becoming the Project manager of the 50-cubesat QB50 mission. He was visiting
research at NASA Ames and Stanford, USA. Today, he entertains a research
portfolio in applied system engineering research for small satellites, reentry
communication blackout and interplanetary missions.
---|---
|  Chiara Vittoria Turtoro is an Associate Legal Counsel at SES in Luxembourg,
working mainly on institutional and governmental contracts. After majoring in
international law with honours at Luiss Guido Carli University, Rome, in 2018,
she enrolled in the Master in Space, Communication and Media Law at the
University of Luxembourg, where she successfully graduated in 2022. She is
strongly passionate about the field of Space and Electronic Communication Law,
their developments and future applications in light of the latest ground-
breaking technologies.
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|  Frank Zeppenfeldt works in satellite communications group of the European
Space Agency (ESA). Frank has been initiating several activities in the area
of IoT, M2M and 5G via satellite, and looks also in a number of spectrum and
regulatory aspects. He is involved in the implementation of adaptations of 5G
protocols for satellite, such that satellite and terrestrial communications
can be further integrated. Before that, Frank worked on IP networking,
satellite communications and security for NATO NCIA (then NC3A) The Hague and
was responsible for the network architectures during various exercises. Within
EUMETSAT (European Organization for Meteorological Satellites), Frank was
responsible for the ground segment network for some of the METEOSAT
satellites.
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|  Petros Pissias is a Data systems manager at the European Space Agency,
located at the European Space Operations Center (ESOC). He is focusing
currently on MBSE, Cybersecurity and activities related to support systems for
mission operations. He was previously involved in software systems for ground
stations and had specialized in monitoring and control systems. Petros studied
informatics and telecommunications, did a masters in advanced distributed
systems and worked in the software industry for several years before joining
the European Space Agency in 2009.
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|  Professor Dr. Mahulena Hofmann is holder of the SES Chair in Space, SatCom
and Media Law at the University of Luxembourg. Her main areas of interest are
space law and telecommunication law. Since 2016, she serves as director of the
Master Program in Space, Communication and Media Law. In 2016, she was head of
an international team which analysed the framework of space resources
activities; afterwards, she has been working on a Draft general space
legislation of Luxembourg. Several times, she was member of the Luxembourg
delegation to the Legal Sub-Committee of the UN COPUOS. Between 2017 and 2019,
she was representing the University in The Hague International Space Resources
Governance Group. M. Hofmann is member of the International Astronautical
Academy, and of the Board of the International Institute of Space Law which
awarded her a Distinguished Service Award in 2020. In 2020, she supported the
UNOOSA in the preparation of an online e-learning course in space law, in
2021, she was nominated member of the DIFC Courts of Space Working Group.
Regularly, she is lecturing space and telecommunication law also at the
Charles University in Prague and other universities abroad. M. Hofmann is
author of more than 100 articles and nine books; in 2019, she published an
“Introduction to Space Law” with Tanja Masson-Zwaan, in 2022, the Commentary
on “Space Legislation of Luxembourg” with her team, and in 2023, “Space Law in
a Networked World” with PJ Blount.
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|  Professor Dr. Symeon Chatzinotas (Fellow, IEEE) received the M.Eng. degree
in telecommunications from the Aristotle University of Thessaloniki,
Thessaloniki, Greece, in 2003, and the M.Sc. and Ph.D. degrees in electronic
engineering from the University of Surrey, Surrey, U.K., in 2006 and 2009,
respectively. He is currently a Full Professor/ Chief Scientist I and the Head
of the SIGCOM Research Group at SnT, University of Luxembourg. In the past, he
was a Visiting Professor at the University of Parma, Italy, and he was
involved in numerous research and development projects for the National Center
for Scientific Research Demokritos, the Center of Research and Technology
Hellas, and the Center of Communication Systems Research, University of
Surrey. He was a co-recipient of the 2014 IEEE Distinguished Contributions to
Satellite Communications Award, the CROWNCOM 2015, 2018 EURASIC JWCN and 2022
WCNC Paper Award. He has (co)authored more than 500 technical articles in
refereed international journals, conferences, and scientific books. He is
currently on the editorial board of the IEEE Transactions on Communications,
IEEE Open Journal of Vehicular Technology, and the International Journal of
Satellite Communications and Networking.
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