CN112822696B - User position-based low-orbit satellite beam closing method - Google Patents

User position-based low-orbit satellite beam closing method Download PDF

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CN112822696B
CN112822696B CN202110048613.2A CN202110048613A CN112822696B CN 112822696 B CN112822696 B CN 112822696B CN 202110048613 A CN202110048613 A CN 202110048613A CN 112822696 B CN112822696 B CN 112822696B
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唐伦
朱丹青
孙移星
李子煜
宋艾遥
梁承超
陈前斌
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Chongqing University of Post and Telecommunications
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/24—Cell structures
    • H04W16/28—Cell structures using beam steering
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
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Abstract

The invention relates to a user position-based low-orbit satellite beam closing method, and belongs to the technical field of communication. The method comprises the following steps: the satellite determines a beam number covering the user by acquiring longitude and latitude coordinate information of the user and satellite subsatellite points; a dynamic beam closing strategy is provided, and a satellite selects to close beams which are overlapped and covered in a part of networks according to the user coverage condition in the networks. The invention provides a beam closing method suitable for a low earth orbit satellite communication system by combining the characteristics of the low earth orbit satellite communication system, saves a large amount of beam resources under the condition of ensuring the coverage of service users and reduces the switching times among user beams.

Description

User position-based low-orbit satellite beam closing method
Technical Field
The invention belongs to the technical field of communication, and relates to a low-orbit satellite beam closing method based on user positions.
Background
Unlike fixed base stations in cellular networks, cellular network cells can adaptively adjust coverage while satellite beams are dynamically changing and cannot adaptively adjust coverage, so existing base station turn-off strategies are not suitable for use in dynamic satellite scenarios.
In a low-orbit satellite communication scene, the conditions of a high-latitude area and a low-latitude area are obviously different, all beams are in an open state in the low-latitude area in order to ensure the full coverage of the low-latitude area, the beams start to gradually overlap when the satellite moves to the high-latitude area, and the beam density of the area with higher latitude is higher. The beam closing method suitable for the satellite communication scene can be provided based on the characteristics of fixed running orbit, predictable beam covering position, correlation between beam density and latitude position and the like of satellite communication.
Disclosure of Invention
In view of the above, the present invention provides a method for turning off a low-earth orbit satellite beam based on a user position. A beam closing method suitable for the low-orbit satellite communication system is provided by combining the characteristics of the low-orbit satellite communication system, so that a large amount of beam resources are saved and the switching times among user beams are reduced under the condition of ensuring the coverage of service users.
In order to achieve the purpose, the invention provides the following technical scheme:
a method of determining a beam covering a user satellite, comprising the steps of:
the method comprises the following steps: taking a satellite as a coordinate origin, taking the running direction of the satellite as an X axis, taking the direction from the satellite to the center of the earth as a Z axis, determining a Y axis according to a left-hand rule, and establishing a satellite body coordinate system;
step two: defining the space direction v ═ alpha of the satellite spot beam B by taking the satellite body coordinate system as referenceb,βbIn which α isbIs an azimuth angle, betabIs a pitch angle;
step three: calculating the direction U ═ alpha of the satellite S pointing to the terminal U in the satellite body coordinate systemu,βuIn which α isuAzimuth angle of the terminal with respect to the direction of satellite travel, betauIs the terminal elevation;
step four: further converting into space vector, and calculating to obtain OXYZ representation corresponding to space vector, i.e. v ═ { x }b,yb,zbJ and u ═ xu,yu,zu}；
Step five: calculating to obtain a space included angle theta' between the beam direction and the satellite terminal direction according to the space angle relation;
step six: by judging the space angle theta' and the beam width angle theta of the beam antennawDetermines whether the user is covered by spot beam B.
A method for low earth orbit satellite beam closing based on user position, comprising the steps of:
the method comprises the following steps: a problem model is established, and the research objective of the beam closing scheme is to close overlapping beams in the network as much as possible and minimize the number X of service beams in the network on the premise of ensuring that a service user is covered by the beams, which is specifically described as follows:
Figure BDA0002898387180000021
Figure BDA0002898387180000022
wherein a user beam dependent coverage factor is defined
Figure BDA0002898387180000024
Represents the user U at time kjIs wave beam BiThe case of overlay.
Step two: for the solution of the closable beam set, the specific algorithm is as follows:
1) input a set cluster { U ] consisting of N sets i1, 2., N }, each set UiContaining M elements Ui＝{e i,j1, 2.., M }, and each set U is given a set of values UiElement e in (1)i,jArranged in the order from small to large.
2) Query all sets UiThe elements with the most occurrence times are arranged from small to large, and one element e is randomly selectedkStore the element in set BkIn (1).
3) Deleting element e contained in collection clusterkUpdate the cluster of sets { U }i}。
4) Judging a cluster { U }iJudging whether the current is an empty set or not, and if so, jumping to the step 5; otherwise, returning to the step 2.
5) The algorithm is finished and the set B is outputk＝{e k1, 2.., L }.
The set of beams which can be closed in the current network can be effectively solved through the algorithm, and further the set of beams can be solved
Figure BDA0002898387180000023
I.e. set of algorithm outputs BkThe number of the elements in (B).
Step three: and (4) determining the value of the time interval tau, namely firstly, taking the time interval of adjacent satellites in the same orbit passing through the same latitude as a period T.
The period T is sliced according to the time of the user covered by the wave beam in the network, and the time T when the covered state of the user is changed is usedkThe period T is divided into a finite number of time domains.
Wherein, the moment when a certain user enters or moves out of any beam coverage area is taken as decision time tkThe optimal value of the decision time interval τ is a variable, depending on the time when two adjacent users are changed by the covered state, i.e., τ ═ tk+1-tk。
The invention has the beneficial effects that: the coverage area of each wave beam of the low-orbit satellite on the earth surface is in an irregular ellipse, and the ideal circular wave beam coverage area calculation method is not suitable for a low-orbit satellite scene.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and combinations particularly pointed out hereinafter.
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For the purposes of promoting a better understanding of the objects, aspects and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic diagram of an auxiliary satellite body coordinate system in the method of the present invention;
FIG. 2 is a schematic diagram of an azimuth angle of a terminal in the method of the present invention;
FIG. 3 is a schematic diagram of an elevation angle of a terminal in the method of the present invention;
FIG. 4 is a schematic diagram showing the relationship between the half-wave beam width angle and the beam coverage area in the method of the present invention;
FIG. 5 is a flowchart illustrating a method for determining a beam covering a user according to the present invention;
fig. 6 is a value diagram of the decision time interval τ in the method of the present invention.
Detailed Description
The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention in a schematic way, and the features in the following embodiments and examples may be combined with each other without conflict.
Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in the drawings in which there is no intention to limit the invention thereto; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.
The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc., based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of description, but it is not an indication or suggestion that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes, and are not to be construed as limiting the present invention, and the specific meaning of the terms may be understood by those skilled in the art according to specific situations.
A method of determining a beam covering a user satellite, comprising the steps of:
the method comprises the following steps: taking a satellite as a coordinate origin, taking the running direction of the satellite as an X axis, taking the direction from the satellite to the center of the earth as a Z axis, determining a Y axis according to the left-hand rule, and establishing a satellite body coordinate system as shown in figure 1;
step two: defining the space direction v ═ alpha of the satellite spot beam B by taking the satellite body coordinate system as referenceb,βbIn which α isbIs an azimuth angle, betabIs a pitch angle;
step three: calculating the direction U ═ alpha of the satellite S pointing to the terminal U in the satellite body coordinate systemu,βuIn which α isuAzimuth angle of the terminal with respect to the direction of satellite travel, betauIs the terminal elevation;
azimuth angle alpha of terminal relative to satelliteuThe calculation method of (2) is as follows:
the coordinates S (lon1, lat1) of the satellite subsatellite point and the coordinates U (lon2, lat2) of the terminal are obtained, as shown in fig. 2, a coordinate system is established in the longitude and latitude direction of the earth, and alpha is the angle value of the terminal to the north and east relative to the satellite position. The formula of the three-face cosine can be obtained as follows:
Figure BDA0002898387180000041
Figure BDA0002898387180000042
due to the orbital inclination angle beta of the constellation design, the azimuth angle alpha of the terminal relative to the running direction of the satelliteuThe calculation formula is as follows:
αu＝α-90°-β
terminal elevation angle betauThe calculation method of (2) is as follows:
as shown in FIG. 3, the radius of the earth is Re, the height of the satellite is h, the earth center is O, the satellite is S, the terminal is U, and β is known from the figureuI.e. the elevation angle of the terminal with respect to the satellite. From the plane cosine equation:
Figure BDA0002898387180000043
wherein,
Figure BDA0002898387180000046
is the geocentric angle that the satellite and the user sandwich.
The formula of the plane sine is given as:
Figure BDA0002898387180000044
Figure BDA0002898387180000045
thereby obtaining the terminal elevation angle betau。
Step four: further converting into space vector, and calculating to obtain OXYZ representation corresponding to space vector, i.e. v ═ { x }b,yb,zbJ and u ═ xu,yu,zu}：
Figure BDA0002898387180000051
Figure BDA0002898387180000052
Step five: and calculating a space included angle theta' between the beam direction and the satellite terminal direction according to the space angle relation:
Figure BDA0002898387180000053
step six: as shown in fig. 4, the beam width angle θ of the beam antenna is determined by determining the spatial angle θwDetermines whether the user is covered by spot beam B. For theFor the beam B and the terminal U, when the space angle theta' between the satellite terminal direction and the beam direction is smaller than the half wave number width of the beam
Figure BDA0002898387180000059
The terminal is considered to be covered by the beam, otherwise the terminal is considered not to be in the beam coverage.
A specific procedure for determining the covered user beam is shown in fig. 5.
The low-orbit satellite beam closing method based on the user position comprises the following steps:
the method comprises the following steps: a problem model is established, and the research objective of the beam closing scheme is to close overlapping beams in the network as much as possible and minimize the number X of service beams in the network on the premise of ensuring that a service user is covered by the beams, which is specifically described as follows:
Figure BDA0002898387180000054
Figure BDA0002898387180000055
wherein a user beam dependent coverage factor is defined
Figure BDA00028983871800000510
Represents the user U at time kjIs wave beam BiIn the case of coverage, there are:
Figure BDA0002898387180000056
the following steps are provided:
Figure BDA0002898387180000057
first pair of closable beam set BkNumber of middle element
Figure BDA0002898387180000058
And (6) solving.
Step two: for the solution of the closable beam set, a set cluster { U ] composed of N sets is input i1, 2., N }, each set UiContaining M elements Ui＝{e i,j1, 2.., M }, and each set U is given a set of values UiElement e in (1)i,jArranged in the order from small to large.
Query all sets UiThe elements with the most occurrence times are arranged from small to large, and one element e is randomly selectedkStore the element in set BkIn (1).
Deleting element e contained in collection clusterkUpdate the cluster of sets { U }i}。
Judging a cluster { U }iJudging whether the current is an empty set or not, and if so, jumping to the step 5; otherwise, returning to the step 2.
The algorithm is finished and the set B is outputk＝{e k1, 2.., L }.
The set of beams which can be closed in the current network can be effectively solved through the algorithm, and further the set of beams can be solved
Figure BDA0002898387180000061
I.e. set of algorithm outputs BkThe number of the elements in (B).
Step three: and (4) determining the value of the time interval tau, namely firstly, taking the time interval of adjacent satellites in the same orbit passing through the same latitude as a period T.
Taking the scenario of two users as an example, the period T is sliced according to the time that the user is covered by the beam, as shown in fig. 6.
User U1The situation covered by the beam during the period T is shown in FIG. 6, from T0Time begins to t4Time instant is beamformed B1Covering, from t2Time t7Time instant is beamformed B2Covering, from t3Time t10Time instant is beamformed B3And (6) covering. Accordingly, useHousehold U2The beam coverage of (a) can also be represented in the time axis.
Wherein, the moment when a certain user enters or moves out of any beam coverage area is taken as decision time tkThe optimal value of the decision time interval τ is a variable, depending on the time when two adjacent users are changed by the covered state, i.e., τ ═ tk+1-tk. As shown in FIG. 6, user U1Enter B2Time t of beam coverage2And user U1Enter B3Time t of beam coverage3The interval of (d) is τ.
Let us assume at tkTo tk+1Arbitrary value t in time periodlAs the beam off decision time. Due to the fact that at tkTo tlDuring the time period, no element in the beam set covering any user changes, so at tlThe constraint condition and the objective function of the moment decision are both equal to the value at tkThe time is the same.
Finally, the above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the claims of the present invention.

Claims (3)

1. A low orbit satellite beam closing method based on user position is characterized in that: the method comprises the following steps:
s1: acquiring longitude and latitude coordinate information of a user and satellite subsatellite points, and determining a beam number capable of covering the user;
s2: solving a closable beam set in the network by taking the closed satellite beam as a target based on the constraint that all users in the network can be covered by the satellite beam;
s3: turning off all beams in the set;
in S1, the beam number that can cover the user is determined as:
s11: taking a satellite as a coordinate origin, taking the running direction of the satellite as an X axis, taking the direction from the satellite to the center of the earth as a Z axis, determining a Y axis according to a left-hand rule, and establishing a satellite body coordinate system;
s12: defining the space direction v ═ alpha of the satellite spot beam B by taking the satellite body coordinate system as referenceb,βbIn which α isbIs an azimuth angle, betabIs a pitch angle;
s13: calculating the direction U ═ alpha of the satellite S pointing to the terminal U in the satellite body coordinate systemu,βuIn which α isuAzimuth angle of the terminal with respect to the direction of satellite travel, betauIs the terminal elevation;
s14: converting into space vector, and calculating to obtain OXYZ representation corresponding to space vector, i.e. v ═ { x%b,yb,zbJ and u ═ xu,yu,zu}；
S15: calculating a space included angle theta 'between the beam direction and the satellite terminal direction according to the space angle relationship, and judging the space included angle theta' and the beam width angle theta of the beam antennawDetermines whether the user is covered by the spot beam B;
in S2, the closable beam set in the network is solved as follows:
s21: input a set cluster { U ] consisting of N setsi1, 2., N }, each set UiContaining M elements Ui＝{ei,j1, 2.., M }, and each set U is given a set of values UiElement e in (1)i,jArranged from small to large;
s22: query all sets UiThe elements with the most occurrence times are arranged from small to large, and one element e is randomly selectedkStore the element in set BkPerforming the following steps;
s23: deleting element e contained in collection clusterkUpdate the cluster of sets { U }i}；
S24: judging a cluster { U }iJudging whether the current time is a null set, if so, jumping to the step S25; otherwise, return to step S22;
s25: the algorithm is finished and the set B is outputk＝{ek1, 2.., L }.
2. The method of claim 1, wherein the low earth orbit satellite beam is turned off based on the location of the user, and wherein: in S2, taking the time interval of the adjacent satellites in the same orbit passing through the same latitude as a period T to take the value of the decision time interval τ; the period T is sliced according to the time of the user covered by the wave beam in the network, and the time T when the covered state of the user is changed is usedkDividing the period T into a finite number of time domains; wherein, the moment when a certain user enters or moves out of any beam coverage area is taken as decision time tkThe optimal value of the decision time interval τ is a variable, depending on the time when two adjacent users are changed by the covered state, i.e., τ ═ tk+1-tk。
3. The method of determining a beam for covering a user according to claim 1, wherein: and the beams adopt a low-orbit satellite network of a circular beam model.
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CN113922865B (en) * 2021-10-12 2023-07-25 重庆邮电大学 Energy optimization method of multi-beam low-orbit satellite in high-latitude scene
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009130801A (en) * 2007-11-27 2009-06-11 Mitsubishi Electric Corp Helicopter-satellite communication system, helicopter-carried communication apparatus used therefor and ground station communication apparatus
CN110838867A (en) * 2019-10-23 2020-02-25 西安空间无线电技术研究所 Medium-low orbit satellite constellation and beam design method thereof
CN111585635A (en) * 2020-04-17 2020-08-25 中国人民解放军国防科技大学 Satellite internet system design method based on space-frequency hybrid multiple access mode

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2365646A1 (en) * 2010-03-12 2011-09-14 Inmarsat Global Limited Satellite beam monitoring by using a monitoring satellite
US10244453B2 (en) * 2015-10-13 2019-03-26 Qualcomm Incorporated Method and apparatus for inter-satellite handovers in low-earth orbit (LEO) satellite systems

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009130801A (en) * 2007-11-27 2009-06-11 Mitsubishi Electric Corp Helicopter-satellite communication system, helicopter-carried communication apparatus used therefor and ground station communication apparatus
CN110838867A (en) * 2019-10-23 2020-02-25 西安空间无线电技术研究所 Medium-low orbit satellite constellation and beam design method thereof
CN111585635A (en) * 2020-04-17 2020-08-25 中国人民解放军国防科技大学 Satellite internet system design method based on space-frequency hybrid multiple access mode

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
关于低轨卫星通信的分析及我国的发展建议;陈山枝;《电信科学》;20200620;全文 *

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