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B2,1,4

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66th International Astronautical Congress, Jerusalem, Israel. Copyright ©2015 by Yaliny. All rights reserved.
IAC-12-B2.1.4
MOBILE SATELLITE COMMUNICATION SYSTEM BASED ON NEW DIGITAL PHASED ARRAY
BEAMFORMING TECHNOLOGY
Mr. Alexander Kharlan
Yaliny, Russian Federation, alexander.kharlan@yaliny.com
Mr. Vasily Ruchenkov
Yaliny, Russian Federation, vasily.ruchenkov@yaliny.com
Mr. Vadim Teplyakov
Yaliny, Russian Federation, vadim.teplyakov@yaliny.com
Yaliny is a young and innovative company whose aim is to create a satellite communication system with a whole
new level of performance. It is planned that the system will, having been fully deployed, provide communication
services and fast Internet connection to any customer all over the globe. First and main segment will be a satellite
constellation, consisting of 135 satellites in low earth orbits, each equipped with a hybrid phased array antennae
combining digital and analogue beamforming. The highlight of the phased array itself is the beamformer fully
developed by Yaliny engineers. It is essentially a PCB – a dielectric base with metallic layers, providing transmission
and receiving linearly polarized signal types. The main advantage here is that for deviating the antennae's directional
pattern only half as much controlling elements are needed comparing to traditional phased array structure. This is
achieved due to multimode structure of the beamformer. Its construction also provides an opportunity to combine
two PCBs into a special crossed construction, thus with different profiles of independent powering of the PCBs any
kind of polarization can be attained. The second segment of the communication system will be its ground
infrastructure. The satellites communicating with each other using a specially developed intersatellite optical
communication hardware will also use a separate dish antenna for broadband connection with ground stations, via
which they will be able to connect to the Internet. It is planned to strategically locate ground stations in different
regions of the world to provide fast and convenient communication services. The third segment is the customer
terminal – a device size of a regular smartphone capable of communicating with customers' smartphones or
computers using Wi-Fi or Bluetooth, and the satellites. The link is designed so that its margin will allow to have up
to several million users all over the world utilizing the network simultaneously. Today the company already
possesses all the technologies needed for the cause as well as the communication system prototype already
manufactured.
I. INTRODUCTION
In the 21st century mobile satellite communication
can represent a paradigm shift to how a global
communication network can be established. Satellites
rapidly become significantly cheaper every day, with
new technologies appearing every now and then which
can drastically boost their performance, be it a
communication satellite or not.
At the same time, mobile communications develop
not so fast nowadays, one of the major issues with them
being the roaming – a cost prohibitive feature leading to
a fact that the vast majority of people have next to no
communication at all while abroad, except for the WiFi.
Yaliny is an innovative company whose aim is to
create a satellite communication system with a whole
new level of performance. It is planned that the system
will, having been fully deployed by the year 2018,
provide communication services and fast Internet
connection to any customer all over the globe.
IAC-15-B2.1.4
Being the one artificial object to fly over the state
borders without any formalities involved, a satellite is a
primary means of connecting people in the future.
Satellite communications are by no means a new
solution: a number of such networks is already present.
But having been deployed a long time ago some of them
have become obsolete, due to their initial price charging
ridiculous fees for below average quality or just poor
services. To replace them the use of all the cutting edge
technologies available is needed for the solution to be
cost-effective and flexible. That is why Yaliny’s
primary goal is to merge the newest satellite
technologies into an efficient solution to provide
communication services all over the globe.
Today when new satellite communication systems
are planned, requirements lodged on their antennae
systems become more and more stringent and
contradictory: high efficiency and power are often
demanded as well as multibeam directional pattern
forming and adaptive control, organized in severe space
conditions. Thus for the purpose of providing mobile
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66th International Astronautical Congress, Jerusalem, Israel. Copyright ©2015 by Yaliny. All rights reserved.
satellite communication services only phased array
antennae system can efficiently solve all the problems
posed.
This paper presents an overview of the Yaliny’s
future LEO satellite communication system, its concept,
major features of the satellite being designed, and gives
a description of its payload and engineering solutions
involved in its design.
II. CONSTELLATION CONCEPT
This section provides a description of the
constellation concept, as well as describes how the
global coverage demands are being met. It also gives an
overview of launch possibilities and of how they affect
the whole mission plan.
II.I Operating constellation
To effectively operate the communication system
has to provide communication services all over the
world. The coverage must be global – any subscriber
must have a complete access to all the services of the
system regardless of his location on the globe.
Thus, having in mind that GEO satellites as well as
the others operating on congruent altitudes cannot
provide the required performance of the communication
system due to the excessive path loss, a network of at
least several dozen LEO satellites is needed to provide a
global coverage.
Yaliny constellation will consist of 135 operating
satellites and also a number of additional satellites for
redundancy purposes, some of them in orbit and other
ones on Earth.
Orbital planes
The satellites will be deployed in nine different
orbital planes, each orbit Sun-synchronous (SSO), with
RAAN difference
  22.5
Fig. I: Orbital planes positioning.
IAC-15-B2.1.4
Orbital planes and how they are positioned can be
seen on fig. I.
Though the satellites are not built for Earth
observation, and the choice of the SSO as an operational
orbit may seem questionable, it is in fact justified. As
the satellites are very energy-effective with up to 10 kW
of power being consumed by the payload and the
subsystems combined, it is highly advisable to have a
comparatively simple way of gimballing the solar
panels in order to harvest a maximum possible amount
of energy. One of the ways to reduce the overall
complexity of the solar array mechanical hardware is to
place a satellite into an orbit where the solar beta-angle
remains the same or approximately the same during the
mission lifetime. SSO is such an orbit. It allows us to
assign a certain beta-angle to each orbit, and this same
angle will determine the position of one of the axis of
the solar panel. This also simplifies the thermal
protection system – the solar radiation flow vector
always rotates the same way, which does not vary, as
the beta-angle does not change, depending almost only
on the orbit local time of ascending node (LTAN).
In-orbit positioning
Each of the nine orbital planes has 15 operating
satellites in it. The difference in the arguments of
latitude of any two neighbour satellites in one orbital
plane will be
u  24
[2]
Besides, positions of two corresponding satellites in
two neighbour planes so differ that, if looking from the
satellite along its velocity vector, the satellite to the
right is 16 degrees ahead, and the satellite to the left is 8
degrees ahead (Table I):
Plane#1
[1]
Plane#2
Plane#3
Plane#4
u = 32°
Sat#3.2
u = 24°
Sat#1.2
Sat#4.2
u = 16°
Sat#2.1
u = 8°
Sat#3.1
u = 0°
Sat#1.1
Sat#4.1
u = 352°
Sat#2.15
u = 344°
Sat#3.15
Table I: Initial satellite positioning net. Such positioning
allows any satellite to be in the centre of a regular
hexagon, each apex of the hexagon being another
satellite.
All satellites are connected with each other with an
intersatellite optical link. Each satellite can connect with
the satellite flying ahead of it and the one flying behind
in the same orbit, and with two satellites in each of the
neighbour planes. For example, satellite #3.1 (see Table
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66th International Astronautical Congress, Jerusalem, Israel. Copyright ©2015 by Yaliny. All rights reserved.
I) connects to satellites 3.2, 3.15 (in the same orbital
plane), 2.1, 2.15, 4.1, and 4.2 (in neighbour planes).
Thus, the described positioning of the satellites
makes it possible to maintain full coverage at any
moment of the time. Coverage zones intersect each
other, with interpenetration between coverage zones
being less significant in equatorial areas and more
significant in polar areas. Having in mind the fact that
the majority of the consumers dwell at latitudes of
25..30 or more degrees, the intersection zones may be
used in order to distribute the subscribers in them
between two satellites, thus significantly decreasing
their peak loads.
II.II Redundancy
It couldn’t be very well expected that such a vast
amount of satellites will work for years without any
failures. In a system with more than a hundred operating
spacecraft there must be a number of additional
satellites strategically allocated between the orbits for
redundancy.
The approach to the problem may vary, but the key
principle of it remains the same: every single element at
any level of the system must be designed so that the
system meets the reliability demands without enormous
amounts of expensive redundant elements.
II.III Launch and deployment
Bla with an equation.

m m
F12  G   1  22  û12
r2  r1
II.V Graph Lines, Drawings and Tables
Use black ink on white manuscript and position to fit
within one of the columns on the page, and ensure that
they remain still readable.
Tables with a moderate amount of information
should be positioned within one column. Tables, graphs
or pictures with large amounts of information may
extend across two columns.
Venus
Earth
Mars
Jupiter
M/ME
0.82
1
0.11
317.89
e
0.007
0.017
0.093
0.048
R (AU)
0.7233
1
1.524
5.203
i (deg)
3.40
0
1.85
1.30
T (years) 0.62
1
1.88
11.86
Table X: Title of table, left justified, subsequent text
indented. Heading centred. Do not use vertical lines
within the table; use horizontal lines only to separate
headings from table entries
II.VI Captions, Graph Axes, Legends
Captions, graph axes, legends, etc. should be large
enough to remain readable.
II.VII Footnotes, Symbols and Abbreviations
Footnotes should be cited using symbols in this
order: *, t, :t, §, <J[, **, tt, :t:t. Use only standard
symbols and abbreviations in text and illustrations.
II.VIII Page Numbers
Indicate page numbering at the bottom of each page.
[1]
II.VI Illustrations and Captions
It is important to remember that all artwork,
captions, figures, graphs and tables will be reproduced
exactly as you submitted them. (Company logos and
identification numbers are not permitted on your
illustrations).
III. MISSION ANALYSIS
This section provides an overview of the mission
plan of every satellite operating within the Yaliny
constellation. It describes the satellite’s deployment, the
process of its delivering itself to the operating point, as
well as how the stationkeeping maneuvers are
performed to provide the required mission lifetime.
III.I. First hours of flight
Bla bla
III.II. Maneuvering
Bla bla
III.III. Stationkeeping
Bla bla
Fig. X: Title of the figure, left justified, subsequent text
indented. Place figures at the top or bottom of a
column wherever possible, as close as possible to the
first references to them in the manuscript. Restrict
them to single-column width unless this would make
them illegible.
IV. SATELLITE CONCEPT
The ways of meeting the mission requirements and
engineering solutions implemented in the satellite are
discussed in this section. It gives a detailed overview of
the satellite’s subsystems, describes the power supply
scheme and system reliability.
IV.I. Subsystems
IAC-15-B2.1.4
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66th International Astronautical Congress, Jerusalem, Israel. Copyright ©2015 by Yaliny. All rights reserved.
Bla bla
V.II. Вася 2
Bla bla
Bla with a reference1.
IV.II. Power efficiency
Bla bla
IV.III. Reliability
Bla bla
V.III. Вася 3
Bla bla
V. ВАСЯ
VI. CONCLUSIONS
V.I. Вася 1
Bla bla
1
Blaa
IAF Secretariat, 2012, Instructions to the Authors for the 63 rd International Astronautical Congress – Naples
IAC-15-B2.1.4
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