CN114172551A - Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming - Google Patents

Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming Download PDF

Info

Publication number
CN114172551A
CN114172551A CN202111464234.8A CN202111464234A CN114172551A CN 114172551 A CN114172551 A CN 114172551A CN 202111464234 A CN202111464234 A CN 202111464234A CN 114172551 A CN114172551 A CN 114172551A
Authority
CN
China
Prior art keywords
satellite
base station
user
safe
scheduling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111464234.8A
Other languages
Chinese (zh)
Inventor
王熠晨
焦晓芬
王奕欣
王弢
王璋楠
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xian Jiaotong University
Original Assignee
Xian Jiaotong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xian Jiaotong University filed Critical Xian Jiaotong University
Priority to CN202111464234.8A priority Critical patent/CN114172551A/en
Publication of CN114172551A publication Critical patent/CN114172551A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming
    • 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
    • H04W16/02—Resource partitioning among network components, e.g. reuse partitioning
    • H04W16/10—Dynamic resource partitioning
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/02—Arrangements for optimising operational condition
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00—Reducing energy consumption in communication networks
    • Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks

Abstract

The invention discloses a safe transmission method and a system based on satellite opportunistic scheduling and combined beam forming, wherein the method designs a beam forming method for maximizing the safe energy efficiency of a satellite user at a base station and a scheduled satellite through an opportunistic scheduling satellite so as to recognize that the safe transmission rate of the base station user in a low-earth-orbit satellite-ground network is not less than the minimum safe rate gammabThe signal-to-interference-and-noise ratio of the satellite user and the base station user is not less than the threshold value lambdasAnd ΛbAnd the maximum transmitting power of the satellite and the base station is limited by PSAnd PBAs constraint conditions, an optimization problem of maximizing the safe energy efficiency of the satellite user is established and solved, the communication quality of the satellite user and the base station user is ensured under the condition of meeting the constraint of the maximum transmitting power of the satellite and the base station, and meanwhile, the communication quality of the satellite user and the base station user is ensuredThe secure communication of the base station users is guaranteed and the secure energy efficiency available to the satellite users is maximized. The safe transmission between satellite users and base station users in the system is ensured by opportunistic scheduling of the satellite and reasonable design of the beam forming coefficients of the satellite and the base station.

Description

Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming
Technical Field
The invention belongs to the technical field of communication safety, and particularly relates to a safe transmission method and a safe transmission system based on satellite opportunistic scheduling combined beam forming, in particular to a safe transmission method based on satellite opportunistic scheduling combined beam forming in a cognitive low-orbit satellite-ground network.
Background
In the future 6G era, satellite networks will be deeply converged with terrestrial networks into satellite-ground networks to promote global coverage. However, the spectrum resources for wireless communication are limited, and the dramatically increased data traffic will degrade the transmission performance of the satellite-to-ground network. In order to solve the problem, cognitive radio technology is introduced into a satellite-ground network to construct a cognitive low-orbit satellite-ground network (CLSTNs) so as to improve the spectrum utilization rate. Communication security is one of the major research directions of 6G wireless networks, and secure transmission in CLSTNs should be emphasized. Information security has traditionally been secured by encryption in upper layer protocols, however as computer processing speeds increase, this approach becomes unreliable. In recent years, physical layer security techniques have attracted a booming trend in their elimination of complex codec algorithms and key management mechanisms. This technique ensures transmission security by making the Signal-to-Interference Plus Noise Ratio (SINR) of a target receiving user larger than that of an eavesdropper by Interference, beamforming, or the like in the physical layer.
The existing research on secure transmission in the cognitive Satellite-ground network focuses on ensuring the secure transmission requirements of Satellite Users (SUs) without considering the communication security of Base Station users (BU). In addition, the existing research is carried out in a high-orbit single-satellite scene, the number of satellites in a low-orbit satellite constellation is large, and the existing scheme cannot be directly applied to the cognitive low-orbit satellite-ground network. Therefore, a more reasonable secure transmission scheme needs to be designed for the cognitive low-orbit satellite-ground network.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a safe transmission method based on satellite opportunistic scheduling combined beam forming in a cognitive low-orbit satellite-ground network.
In order to achieve the purpose, the invention adopts the technical scheme that: a safe transmission method based on satellite opportunity scheduling and joint beamforming comprises the following steps:
based on a cognitive low-orbit satellite-ground network system; calculating the received signal-to-interference-and-noise ratio of the receiving signals at each receiving node, and calculating the safe speed of the satellite user and the base station user and the safe energy efficiency of the satellite user;
the safety rate of base station users in the cognitive low-orbit satellite-ground network is not less than the minimum safety rate gammabThe signal-to-interference-and-noise ratio of the satellite user and the base station user is not less than the threshold value lambdasAnd ΛbAnd the maximum transmitting power of the satellite and the base station is limited by PSAnd PBAs a constraint condition, establishing an optimization problem that a satellite user can achieve maximum safety energy efficiency;
fixing satellite scheduling vectors, converting non-convex optimization problems into convex optimization problems by utilizing a Dinkelbach algorithm and a D.C. approximation method, solving to obtain beam forming vectors of the satellite and the base station, obtaining an optimal solution by traversing and searching the satellite scheduling vectors, and finally performing beam forming on the base station and the scheduled satellite according to the optimal solution and completing data transmission.
In the cognitive low-orbit satellite-ground network, the cognitive low-orbit satellite-ground network comprises a main network and a secondary network, the main network and the secondary network occupy the same section of spectrum resources, in the main network, a satellite transmits confidential information to a single-antenna satellite user SU through N wave beams, and a single-antenna eavesdropper SE near the single-antenna satellite user SU attempts to eavesdrop the information transmitted to the single-antenna satellite user SU by the satellite; in the secondary network, a base station BS with M antennas sends confidential information to a single-antenna base station user BU under the condition that an eavesdropper BE monitors the information sent by the base station BS; the single-antenna satellite user SU has K satellites in total in the visible range, and the single-antenna satellite user SU can only be served by a single scheduled satellite in one time slot.
In the resolving process, a satellite downlink channel is obtained according to the fact that all links in the cognitive low-orbit satellite-ground network are static slow fading channels and the channels among different beams of the same satellite are independent, and the channel coefficient h of the ground links is Rayleigh distribution.
Calculating the receiving signal-to-noise ratios of the SU, SE, BU and BE positions according to the receiving signals of the SU, SE, BU and BE positions and the beam forming vectors of the satellite and BS positions, and further obtaining the safe rates of the SU and BU positions; the safe energy efficiency is the safe bit number which can be reached by unit energy and bandwidth in signal transmission, and the safe energy efficiency eta at SUskComprises the following steps:
ηsk＝Csk/(||w||2+Pck+||v||2+Pb)
wherein the content of the first and second substances,
Figure BDA0003389691580000031
and
Figure BDA0003389691580000032
representing the beamforming vectors, C, at the satellite and BS, respectivelyskIs a safe rate at SU, PckAnd PbRespectively represent the constant independent transmission power of the satellite and the base station, and k is the serial number of the satellite.
The optimization problem of maximizing the safety energy efficiency which can be reached by the satellite user is as follows:
Figure BDA0003389691580000033
s.t.CTB≥Γb (5a)
CTγs≥Λs (5b)
CTγb≥Λb (5c)
||w||2≤PS (5d)
||v||2≤PB (5e)
Figure BDA0003389691580000034
wherein, C ═ C1,c2...cK]TA scheduling vector representing the satellite, η ═ ηs1,ηs2...ηsk]TAn available SEE vector representing SU, B ═ Cb1,Cb2...Cbk]TSR vector, gamma, representing BUs＝[γs1,γs2...γsk]TAnd gammab＝[γb1,γb2...γbk]TSINR vectors, Γ, representing SU and BU, respectivelybMinimum SR threshold, Λ, indicating that BU safe transmission is satisfiedsAnd ΛbDenotes the minimum SINR requirement, P, of SU and BU, respectivelySAnd PBRepresenting the maximum transmission power of the satellite and the base station, respectively, the constraint (5f) ensuring that there is and only one satellite scheduled in a time slot, ck1 indicates that the kth satellite is scheduled to transmit a signal to SU.
And (3) simplifying the optimization problem into the following convex optimization problem by using a satellite scheduling vector C in the fixed problem:
Figure BDA0003389691580000041
Figure BDA0003389691580000042
Figure BDA0003389691580000043
Figure BDA0003389691580000044
Tr(W)≤PS,W≥0 (10d)
Tr(V)≤PB,V≥0 (10e)
and (5) solving by using a mathematical tool until the change value of the optimization target in the step (10) is not more than the minimum error epsilon or the iteration times reach the maximum, and obtaining a satellite scheduling vector and beam forming vectors of the satellite and the BS.
Solving the optimal satellite scheduling vector and the beam forming vectors of the satellite and the BS by adopting three layers of iterative processes, wherein the three layers of iterative processes are a main loop, an outer loop and an inner loop respectively;
where main searches for the best satellite scheduling vector C in a round-robin fashion*(ii) a Fixing a satellite scheduling vector C in a main cycle and calling an outer cycle to calculate the obtainable maximum safe energy efficiency value corresponding to the satellite scheduling vector C, and finally obtaining the optimal satellite scheduling vector C which enables the optimization target to be maximum by traversing all values of the satellite scheduling vector C*；
Maximum safe energy efficiency η obtainable by SU at given satellite scheduling vector C calculated by outer loopspInitializing the maximum number of iterations imaxMinimum tolerance error ε, current iteration number i and
Figure BDA0003389691580000045
then calling an internal cyclic utilization D.C. approximation method to obtain a given value
Figure BDA0003389691580000046
Time optimal matrix
Figure BDA0003389691580000047
And accordingly pair
Figure BDA0003389691580000048
Updating is carried out until
Figure BDA0003389691580000049
The change value of the energy efficiency is less than epsilon or the current iteration times reach the maximum, so that the optimal safe energy efficiency value is obtained;
inner loop calculation given
Figure BDA00033896915800000410
Time optimal matrix
Figure BDA00033896915800000411
The inner loop first initializes the maximum number of iterations jmaxMinimum tolerance error, epsilon, initial matrix
Figure BDA00033896915800000412
Optimization objective f0With the current number of iterations j, so that
Figure BDA00033896915800000413
Then solving the problem (10) to obtain
Figure BDA00033896915800000414
According to
Figure BDA00033896915800000415
To fj+1Updating until fjThe variation value of (a) is less than epsilon or the current iteration number reaches the maximum, thereby obtaining the optimal matrix
Figure BDA00033896915800000416
On the other hand, the invention also provides a safe transmission system based on satellite opportunistic scheduling combined beam forming, which comprises a safe energy efficiency solving module, an optimization problem constructing module and an optimization problem solving module;
the safe energy efficiency solving module is based on a cognitive low-orbit satellite-ground network system; calculating the received signal-to-interference-and-noise ratio of the receiving signals at each receiving node, and calculating the secret rate of the satellite user and the base station user and the safety energy efficiency of the satellite user;
the safe transmission rate of a base station user in the cognitive low-orbit satellite-ground network is not less than the minimum safe rate gammabThe signal-to-interference-and-noise ratio of the satellite user and the base station user is not less than the threshold value lambdasAnd ΛbAnd maximum transmission power P of satellite and base stationSAnd PBThe limitation is used as a constraint condition, and an optimization problem that the satellite user can achieve the maximum safe energy efficiency is established;
the optimization problem solving module fixes satellite scheduling vectors, converts non-convex optimization problems into convex optimization problems by utilizing a Dinkelbach algorithm and a D.C. approximation method, solves the convex optimization problems to obtain beam forming vectors of the satellite and the base station, obtains an optimal solution through traversal search of the satellite scheduling vectors, and takes the optimal solution as a basis for beam forming of the base station and the scheduled satellite and data transmission completion.
The invention also provides computer equipment which comprises a processor and a memory, wherein the memory is used for storing a computer executable program, the processor reads the computer executable program from the memory and executes the computer executable program, and the processor can realize the safe transmission method based on the satellite opportunity scheduling joint beamforming when executing the computer executable program.
A computer readable storage medium having stored thereon a computer program which, when executed by a processor, is capable of implementing the secure transmission method based on joint beamforming for satellite opportunistic scheduling according to the present invention.
Compared with the prior art, the invention has at least the following beneficial effects:
aiming at the condition that the number of satellites in a low-orbit satellite constellation is large, under the condition that the transmitting power of the satellites and a base station is limited, the safe transmission method based on satellite opportunistic scheduling combined beam forming establishes an optimization problem which simultaneously meets the minimum safe rate constraint of a base station user and the maximization of the safe energy efficiency of the satellite user under the constraint of the minimum signal to interference plus noise ratio of the satellite user and the base station user, solves the optimization problem, and maximizes the safe energy efficiency of the satellite user in the cognitive low-orbit satellite earth network on the premise of ensuring the safe transmission of the base station user.
Moreover, the problem of safety energy efficiency maximization when a satellite is scheduled is considered, the problem is converted into a convex problem based on a Dinkelbach algorithm and a D.C. approximation method, the satellite scheduling vector and the beam forming vector of the satellite and the base station are solved through a three-layer iteration process, the transmission power constraint of the satellite and the base station and the communication signal-to-interference-and-noise ratio requirements of a satellite user and a base station user are finally met, and the safety energy efficiency of the satellite user in the cognitive low-orbit satellite-ground network is maximized on the premise of ensuring the safety transmission of the base station user.
Drawings
Fig. 1 is a system model of a cognitive low-orbit satellite-ground network.
Fig. 2 is a comparison graph of the safe transmission method based on satellite opportunistic scheduling combined beam forming in the cognitive low-earth-orbit satellite network according to the invention and the safe energy efficiency obtained by other schemes under different numbers of beams of satellites.
Fig. 3 is a comparison graph of the safe transmission method based on satellite opportunistic scheduling combined beamforming in the cognitive low-earth-orbiting network according to the present invention and the safe energy efficiency obtained under different maximum transmit power constraints of satellites in other schemes.
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings:
in the cognitive low-orbit satellite-ground network, the cognitive low-orbit satellite-ground network comprises a main network and a secondary network, the main network and the secondary network occupy the same section of spectrum resources, in the main network, a satellite transmits confidential information to a single-antenna satellite user SU through N wave beams, and a single-antenna eavesdropper SE near the single-antenna satellite user SU attempts to eavesdrop the information transmitted to the single-antenna satellite user SU by the satellite; in the secondary network, a base station BS with M antennas sends confidential information to a single-antenna base station user BU under the condition that an eavesdropper BE monitors the information sent by the base station BS; the single-antenna satellite user SU has K satellites in total in the visible range, and the single-antenna satellite user SU can only be served by a single scheduled satellite in one time slot.
In the resolving process, a satellite downlink channel is obtained according to the fact that all links in the cognitive low-orbit satellite-ground network are static slow fading channels and the channels among different beams of the same satellite are independent. The channel coefficient h of the terrestrial link is Rayleigh distribution.
Calculating the receiving signal-to-noise ratios of the SU, SE, BU and BE positions according to the receiving signals of the SU, SE, BU and BE positions and the beam forming vectors of the satellite and BS positions, and further obtaining the safe rates of the SU and BU positions; the safe energy efficiency is the safe bit number which can be reached by unit energy and bandwidth in signal transmission, and the safe energy efficiency eta at SUskComprises the following steps:
ηsk＝Csk/(||w||2+Pck+||v||2+Pb)
wherein the content of the first and second substances,
Figure BDA0003389691580000071
and
Figure BDA0003389691580000072
representing the beamforming vectors, C, at the satellite and BS, respectivelyskIs a safe rate at SU, PckAnd PbRespectively represent the constant independent transmission power of the satellite and the base station, and k is the serial number of the satellite.
When the kth satellite is scheduled, the received signals at SU, SE, BU, BE are respectively expressed as:
Figure BDA0003389691580000073
Figure BDA0003389691580000074
and
Figure BDA0003389691580000075
wherein x and s are the transmission signals of the satellite and the base station BS, respectively, and x and s satisfy E (x) respectively2) 1 with E(s)2) 1, E (·) denotes the expectation of the variable;
Figure BDA0003389691580000076
and
Figure BDA0003389691580000077
respectively representing links Sk-SU，Sk-SE，Sk-BU，Sk-BE, BS-SU, BS-SE, BS-BU, BS-BE, wherein SkRepresents the kth satellite;
Figure BDA0003389691580000078
and
and
Figure BDA0003389691580000079
representing beamforming vectors at the satellite and the BS, respectively;
Figure BDA00033896915800000710
i belongs to s, SE, b, BE and represents Gaussian white noise at SU, SE, BU and BE,
Figure BDA00033896915800000711
κ denotes boltzmann's constant, B denotes noise bandwidth, and T denotes noise temperature. The received signal-to-noise ratio at each user is thus calculated as:
Figure BDA00033896915800000712
Figure BDA00033896915800000713
and
Figure BDA00033896915800000714
thus, the safe rate at SU and BU is obtained as follows:
Csk＝max{log2(1+γsk)-log2(1+γsek),0} (2)
Cbk＝max{log2(1+γbk)-log2(1+γbek),0} (3)
secure Energy Efficiency (SEE) is defined as the number of secure bits per unit Energy and bandwidth available for signal transmission, and the secure Energy Efficiency at SU is expressed as:
ηsk＝Csk/(||w||2+Pck+||v||2+Pb) (4)
wherein, PckAnd PbRepresenting the constant independent transmission power of the satellite and the base station, respectively.
The safe transmission method based on satellite opportunity scheduling combined beam forming in the cognitive low-orbit satellite-ground network comprises the following steps:
step 1): referring to fig. 1, the following system model is established:
in a cognitive low-orbit satellite-ground network, the network is assumed to comprise a primary network and a secondary network, and the primary network and the secondary network occupy the same spectrum resource. In the main network, the satellite transmits confidential information to a single antenna satellite user SU via N beams, and a single antenna eavesdropper SE in the vicinity of the SU attempts to eavesdrop the information transmitted by the satellite to the SU. In the secondary network, a base station BS with M antennas transmits confidential information to a single-antenna base station user BU in the case where an eavesdropper BE listens to the base station BS transmission information. Because the main network and the secondary network occupy the same frequency band, a single-antenna satellite user SU, a single-antenna eavesdropper SE, a single-antenna base station user BU and an eavesdropper BE can simultaneously receive information from the satellite and the BS. The single-antenna satellite user SU has K satellites in total in the visible range, and the single-antenna satellite user SU can only be served by a single scheduled satellite in one time slot. The channel state information for each link is fully known.
Step 2): and calculating the received signal-to-interference-and-noise ratio based on the received signals of the single-antenna satellite user SU and the single-antenna base station user BU, thereby calculating the safe speed of the single-antenna satellite user SU and the single-antenna base station user BU and the safe energy efficiency of the single-antenna satellite user SU:
all links are static slow fading channels, and the ground links h are Rayleigh distributed. The channels between different beams of the same satellite are independent, the influence of free space path loss, satellite antenna gain and small-scale fading is considered, and the satellite downlink channel is expressed as:
Figure BDA0003389691580000081
wherein, CLλ/4 π d represents the free space path loss, λ is the wavelength, and d represents the distance between the satellite and the user. Beam gain
Figure BDA0003389691580000082
Can be approximated by
Figure BDA0003389691580000083
bmaxIt is indicated that the maximum beam gain is,
Figure BDA0003389691580000091
representing the angle between the user and the center of the satellite beam,
Figure BDA0003389691580000092
representing a 3-dB angle. J. the design is a square1(.) and J3(.) represent the first class of bezier functions of order 1 and 3, respectively. Small scale fading g is modeled using the Lutz channel. The Lutz distribution divides the channel into two states: a Rician distribution representing a "good state" and a "log-normal shaded Rayleigh distribution representing a" bad state ". The probability density expression of the obedience of the received power S under the Rician distribution is
Figure BDA0003389691580000093
I0(. cndot.) represents a first class of modified zero-order Bessel function. Received power obeys p under log-normal shaded Rayleigh distributionRayl(S|S0)＝1/S0 exp(-S/S0) Wherein the short-time average received power S0Obedience distribution
Figure BDA0003389691580000094
Thus, receiving in the Lutz modelThe probability density expression obeyed by the power is:
Figure BDA0003389691580000095
wherein a represents the percentage of time that "bad channels" are present, -0.0177 θ +1.0095 and 0 when θ ≧ 57.0339 °, where θ represents the elevation angle of the satellite; mu and sigma2Means and variance under Rayleigh distribution, respectively, σ -0.0979 θ +8.2036dB and when θ ≧ 83.8321 °, σ -0 dB; c represents the Rice factor, and c is 0.3282 theta-3.9554 dB. Mu satisfies a piecewise function, when theta is less than or equal to 15 degrees, mu is-11 dB, when theta is less than or equal to 25 degrees between 15 degrees, mu is-0.6 theta-2 dB, when theta is less than or equal to 25 degrees, mu is 0.4 theta-27 dB, when theta is less than 35 degrees, mu is 0.3 theta-23.5 dB, when theta is less than 45 degrees between 45 degrees, mu is-0.2 theta-1 dB, when theta is less than 45 degrees, mu is-12 dB. The channel phase of each link obeys 0,2 pi]Are evenly distributed in between.
The transmission signals of the satellite and the BS are x and s respectively, wherein x and s respectively satisfy E (x)2) 1 with E(s)2) 1, E (·) denotes the expectation of the variable. Link Sk-SU，Sk-SE，Sk-BU，Sk-BE, BS-SU, BS-SE, BS-BU, BS-BE are denoted respectively
Figure BDA0003389691580000096
And
Figure BDA0003389691580000097
wherein SkRepresenting the kth satellite. When the kth satellite is scheduled, the received signals at SU, SE, BU, BE are respectively represented as:
Figure BDA0003389691580000098
Figure BDA0003389691580000099
and
Figure BDA00033896915800000910
wherein the content of the first and second substances,
Figure BDA00033896915800000911
and
Figure BDA00033896915800000912
representing the beamforming vectors at the satellite and BS respectively,
Figure BDA00033896915800000913
i belongs to s, SE, b, BE and represents Gaussian white noise at SU, SE, BU and BE,
Figure BDA00033896915800000914
κ denotes the boltzmann constant, B denotes the signal bandwidth, and T denotes the noise temperature. The received signal-to-noise ratio at each user is thus calculated as:
Figure BDA00033896915800000915
Figure BDA0003389691580000101
and
Figure BDA0003389691580000102
thus, the Safe Rate (SR) at the positions of the single-antenna satellite user SU and the single-antenna base station user BU is obtained as follows:
Csk＝max{log2(1+γsk)-log2(1+γsek),0} (2)
Cbk＝max{log2(1+γbk)-log2(1+γbek),0} (3)
secure Energy Efficiency (SEE) is the number of secure bits per unit Energy and bandwidth that can be achieved during signal transmission, and thus the secure Energy Efficiency at SU is:
ηsk＝Csk/(||w||2+Pck+||v||2+Pb) (4)
wherein, PckAnd PbRepresenting the constant independent transmission power of the satellite and the base station, respectively.
Step 3): setting base station user entity in cognitive low-orbit satellite-ground networkMinimum security rate Γ required for existing secure transmissionsbSINR threshold value Lambda for satellite users and base station userssAnd ΛbAnd maximum transmission power P of satellite and base stationSAnd PB。
Step 4): the minimum safety rate gamma required by the base station user to realize the safety transmission in the cognitive low-orbit satellite-ground network set according to the step 3)bSINR threshold value Lambda for satellite users and base station userssAnd ΛbAnd maximum transmission power P of satellite and base stationSAnd PBAnd establishing an optimization problem that the satellite user can achieve the maximum safe energy efficiency by taking the safe transmission rate of the base station user not lower than the minimum safe rate, the signal-to-interference-and-noise ratio of the satellite user and the base station user not smaller than the threshold value and the maximum transmitting power of the satellite and the base station as constraint conditions:
the optimization problem of maximizing the safe energy efficiency that a satellite user can reach can be expressed as:
Figure BDA0003389691580000103
s.t.CTB≥Γb (5a)
CTγs≥Λs (5b)
CTγb≥Λb (5c)
||w||2≤PS (5d)
||v||2≤PB (5e)
Figure BDA0003389691580000104
wherein, C ═ C1,c2...cK]TA scheduling vector representing the satellite, η ═ ηs1,ηs2...ηsk]TAn available SEE vector representing SU, B ═ Cb1,Cb2...Cbk]TSR vector, gamma, representing BUs＝[γs1,γs2...γsk]TAnd gammab＝[γb1,γb2...γbk]TSINR vectors, Γ, representing SU and BU, respectivelybMinimum SR threshold, Λ, indicating that BU safe transmission is satisfiedsAnd ΛbDenotes the minimum SINR requirement, P, of SU and BU, respectivelySAnd PBRepresenting the maximum transmission power of the satellite and the base station, respectively. The constraint (5f) is to ensure that there is and only one satellite scheduled in a time slot, ck1 indicates that the kth satellite is scheduled to transmit a signal to SU.
Step 5): fixing satellite scheduling vectors, converting non-convex optimization problems into convex optimization problems by utilizing a Dinkelbach algorithm and a D.C. approximation method, solving to obtain beam forming vectors of the satellite and the base station, and obtaining optimal solutions through traversal search of the satellite scheduling vectors.
First fix the satellite scheduling vector C in problem (5), which can be simplified to:
Figure BDA0003389691580000111
s.t.log2((1+γbp)/(1+γbep))≥Γb (6a)
γsp≥Λs (6b)
γbp≥Λb (6c)
||w||2≤PS (6d)
||v||2≤PB (6e)
by introducing auxiliary variables ηspThe Dinkelbach algorithm can convert the fractional programming problem shown in problem (6) into equivalentA subtractive form optimization problem. Note the book
Figure BDA0003389691580000112
And
Figure BDA0003389691580000113
Figure BDA0003389691580000114
and
Figure BDA0003389691580000115
while introducing a relaxation variable W ═ wwH，V＝vvHThe optimization problem can be further converted into:
Figure BDA0003389691580000121
s.t.r1(W,V)-r2(W,V)≥Γb(7a)
Figure BDA0003389691580000122
Figure BDA0003389691580000123
Tr(W)≤PS,rank(W)＝1,W≥0 (7d)
Tr(V)≤PB,rank(V)＝1,V≥0 (7e)
if and only if f (η)sp) When 0, the optimal solution for the beamforming vector in problem (6) can be obtained by solving problem (7). And (7) and (7a) are transformed into corresponding linear constraints by using a D.C. approximation method and adopting a first-order Taylor expansion approximation mode aiming at the non-convex objective function (7) and the non-convex constraint (7 a):
Figure BDA0003389691580000124
Figure BDA0003389691580000125
wherein (W, V) represents a function f2(W, V) and r2(W, V) defines the feasible points within the domain. By removing the rank 1 constraint and substituting equations (8), (9) into the problem (7), the problem can be converted to:
Figure BDA0003389691580000126
Figure BDA0003389691580000127
Figure BDA0003389691580000128
Figure BDA0003389691580000129
Tr(W)≤PS,W≥0 (10d)
Tr(V)≤PB,V≥0 (10e)
problem (10) is a convex optimization problem that can be solved using the mathematical tool CVX. Initializing (W, V), calculating the optimal variable values (W, V) of the problem (10) when the (W, V) is given, updating the values (W, V) in the problem to be (W, V), solving the problem (10) again, and iteratively solving the problem (10) by circulating the operation until the change value of the optimization target in the problem (10) is not more than the minimum error epsilon or the current iteration number is maximum.
The invention uses a three-layer iterative process to solve the optimal satellite scheduling vector and the beamforming vectors of the satellite and the BS. The three layers of iteration processes are respectively a main loop, an outer loop and an inner loop. Wherein the content of the first and second substances,the main loop is used for searching the optimal satellite scheduling vector C*. Fixing a satellite scheduling vector C in a main cycle and calling an outer cycle to calculate the maximum obtainable safe energy efficiency value corresponding to the satellite scheduling vector C, and finally obtaining C with the maximum safe energy efficiency by traversing all values of the satellite scheduling vector C*. The outer loop calculates the maximum safe energy efficiency that SU can achieve given C. When the outer loop is called, the maximum number of iterations i is initialized firstmaxMinimum tolerance error ε, current iteration number i and
Figure BDA0003389691580000131
then calling an internal cyclic utilization D.C. approximation method to obtain a given value
Figure BDA0003389691580000132
Time optimal matrix
Figure BDA0003389691580000133
And accordingly pair
Figure BDA0003389691580000134
Updating is carried out until
Figure BDA0003389691580000135
The change value of (2) is less than epsilon or the current iteration number reaches the maximum, so that the optimal safe energy efficiency value is obtained. The role of the inner loop is to calculate the given
Figure BDA0003389691580000136
Time optimal matrix
Figure BDA0003389691580000137
The main solution is to update and iteratively solve the problem (10). When the inner loop is called, the maximum number of iterations j is initialized firstmaxThe minimum tolerance error, epsilon,
Figure BDA0003389691580000138
optimization objective f0With the current iteration number j, then orderIn the problem (10)
Figure BDA0003389691580000139
Then solving the problem (10) to obtain
Figure BDA00033896915800001310
According to
Figure BDA00033896915800001311
To fj+1Updating until fjThe variation value of (a) is less than epsilon or the current iteration number reaches the maximum, thereby obtaining the optimal matrix
Figure BDA00033896915800001312
It should be noted that the optimal matrix finally obtained by solving
Figure BDA00033896915800001313
Is not necessarily 1 because of the introduction of the relaxation condition. When in use
Figure BDA00033896915800001314
When the rank of (1) is 1, the order can be obtained by using a singular value decomposition method
Figure BDA00033896915800001315
When the rank is not 1, a set of approximately optimal solutions can be found by using a Gaussian random method
Figure BDA00033896915800001316
And finally, the base station and the scheduled satellite carry out beam forming according to the optimal solution and complete data transmission.
The pseudo code of the three-layer iteration process of the invention is as follows:
Figure BDA00033896915800001317
Figure BDA0003389691580000141
in the simulation experiment, a Joint high Elevation Priority Satellite Scheduling combined BF Scheme (Joint high Elevation Priority Satellite Scheduling and BF Scheduling, j eassb) and a maximum Service Time Priority Satellite Scheduling combined BF Scheme (Joint maximum Service Time Priority Satellite Scheduling and BF Scheduling, jmstsb) are used as comparison schemes. The simulation scenario and parameter settings are as follows: modeling the simulated low earth orbit satellite constellation as an iridium-like constellation: the total number of satellites is set to 66, the orbital plane is set to 6, the orbital inclination angle is 86.4 degrees, the satellite height is 780km, and the satellite minimum coverage elevation angle is set to 19 degrees. A single satellite can generate 48 beams, each beam having a diameter of 400km and a beam gain bmaxSet to 52 dB. Distances of SU to SE, BU, and BE are set to 0.1D, and 0.11D, respectively, where D denotes the diameter of the satellite beam. The maximum transmit power for the satellite and base station are set to 35dBm and 42dBm, respectively. At a given moment, the elevation angle of the satellite in view of the SU is determined. The latitude and longitude coordinates of the SU are set to (75 °,95 °). According to the set simulation system, the visible range of SU at a certain time has 4 satellites, and the satellite elevation angles are 20.0568 °, 20.1066 °, 27.3138 ° and 31.1373 °. The satellite transmits signals to the SU through the N beams closest to the SU, and the beamforming vector of the satellite is optimized through the channel state information of the N beams. The carrier frequency was 20GHz, the signal bandwidth was 300MHz, the noise temperature was set to 500K, and the 3-dB angle was set to 14 °. The simulation was performed under the above conditions unless parameters were set specifically. All simulation curves were averaged over 500 random channel realizations.
Referring to fig. 2, compared with the JHEASSB scheme and the JMSTSSB scheme, the secure transmission method based on satellite opportunistic scheduling combined beamforming in the cognitive low-earth-orbit network provided by the present invention can enable a satellite user to obtain maximum secure energy efficiency under different beam numbers. The safe energy efficiency achievable by the present invention is about 100% higher than that achievable by the jhaessb; compared with JMSTSSB, the safe energy efficiency of the invention is improved by more than 150%. According to the scheme, the optimal channel transmission quality between the current scheduling satellite and the satellite user can be ensured through opportunistic satellite scheduling, and under the condition, more effective beam forming can be carried out according to the channel state information. As the number of beams increases, the safe energy efficiency gradually increases and eventually reaches convergence. The increase in the number of beams means that resources available for beamforming increase, and thus there is a trend toward an increase in safe energy efficiency. When the number of the beams is increased to more than 6, because the newly added beams are farther away from the satellite user, the channel gain under the beams is smaller and smaller, the expected effect of the beam forming by using the beams is gradually reduced, and finally the safe energy efficiency tends to a certain value.
Referring to fig. 3, the number of beams is set to 6. Compared with the JEASSB scheme and the JMSTSSB scheme, the safe transmission method based on satellite opportunity scheduling combined beam forming in the cognitive low-orbit satellite-ground network provided by the invention can obtain the maximum safe energy efficiency under different satellite maximum power constraints, which proves the superiority of the invention. It can be observed that as the maximum transmit power of the satellite increases, the safe energy efficiency gradually increases and eventually converges. When the maximum transmitting power of the satellite is in the range of 30-36 dBm, the safe energy efficiency obtained by the three schemes is improved to a certain extent along with the increase of the power budget. This shows that within a certain power budget, the safe energy efficiency will increase as the available power resources increase.
On the other hand, the invention also provides a safe transmission system based on satellite opportunistic scheduling combined beam forming, which comprises a safe energy efficiency solving module, an optimization problem constructing module and an optimization problem solving module;
the safe energy efficiency solving module is based on a cognitive low-orbit satellite-ground network system; calculating the received signal-to-interference-and-noise ratio of the receiving signals at each receiving node, and calculating the secret rate of the satellite user and the base station user and the safety energy efficiency of the satellite user;
the safety rate of base station users in the cognitive low-orbit satellite-ground network is not less than the minimum safety rate gammabThe signal-to-interference-and-noise ratio of the satellite user and the base station user is not less than the threshold value lambdasAnd ΛbAnd the maximum transmitting power of the satellite and the base station is limited by PSAnd PBAs a constraint condition, establishing an optimization problem that a satellite user can achieve maximum safety energy efficiency;
the optimization problem solving module fixes satellite scheduling vectors, converts non-convex optimization problems into convex optimization problems by utilizing a Dinkelbach algorithm and a D.C. approximation method, solves the convex optimization problems to obtain beam forming vectors of the satellite and the base station, obtains an optimal solution through traversal search of the satellite scheduling vectors, and takes the optimal solution as a basis for beam forming of the base station and the scheduled satellite and data transmission completion.
In addition, the invention can also provide a computer device, which includes a processor and a memory, where the memory is used to store a computer executable program, the processor reads part or all of the computer executable program from the memory and executes the computer executable program, and when the processor executes part or all of the computer executable program, the secure transmission method based on satellite opportunity scheduling joint beamforming according to the invention can be implemented.
In another aspect, the present invention provides a computer-readable storage medium having a computer program stored therein, where the computer program, when executed by a processor, can implement the method for secure transmission based on joint beamforming for opportunistic scheduling of satellites according to the present invention.
The computer device may be a notebook computer, a desktop computer or a workstation.
The processor may be a Central Processing Unit (CPU), a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), or an off-the-shelf programmable gate array (FPGA).
The memory of the invention can be an internal storage unit of a notebook computer, a desktop computer or a workstation, such as a memory and a hard disk; external memory units such as removable hard disks, flash memory cards may also be used.
Computer-readable storage media may include computer storage media and communication media. Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. The computer-readable storage medium may include: a Read Only Memory (ROM), a Random Access Memory (RAM), a Solid State Drive (SSD), or an optical disc. The Random Access Memory may include a resistive Random Access Memory (ReRAM) and a Dynamic Random Access Memory (DRAM).
The foregoing is a detailed description of the invention and is not to be taken as limiting, since numerous simple deductions and substitutions may be made by those skilled in the art without departing from the spirit of the invention, which is to be construed as falling within the scope of the invention as defined by the appended claims.

Claims (10)

1. A safe transmission method based on satellite opportunity scheduling and joint beamforming is characterized by comprising the following steps:
based on a cognitive low-orbit satellite-ground network system; calculating the received signal-to-interference-and-noise ratio of the receiving signals at each receiving node, and calculating the safe speed of the satellite user and the base station user and the safe energy efficiency of the satellite user;
the safety rate of base station users in the cognitive low-orbit satellite-ground network is not less than the minimum safety rate gammabThe signal-to-interference-and-noise ratio of the satellite user and the base station user is not less than the threshold value lambdasAnd ΛbAnd the maximum transmitting power of the satellite and the base station is limited by PSAnd PBAs a constraint condition, establishing an optimization problem that a satellite user can achieve maximum safety energy efficiency;
fixing satellite scheduling vectors, converting non-convex optimization problems into convex optimization problems by utilizing a Dinkelbach algorithm and a D.C. approximation method, solving to obtain beam forming vectors of the satellite and the base station, obtaining an optimal solution by traversing and searching the satellite scheduling vectors, and finally performing beam forming on the base station and the scheduled satellite according to the optimal solution and completing data transmission.
2. The secure transmission method based on satellite opportunistic scheduling combined beamforming according to claim 1, wherein in a cognitive low earth-orbiting network, the cognitive low earth-orbiting network comprises a primary network and a secondary network, the primary network and the secondary network occupy the same section of spectrum resources, in the primary network, the satellite transmits confidential information to the single-antenna satellite user SU through N beams, and a single-antenna eavesdropper SE near the single-antenna satellite user SU attempts to eavesdrop the information transmitted by the satellite to the single-antenna satellite user SU; in the secondary network, a base station BS with M antennas sends confidential information to a single-antenna base station user BU under the condition that an eavesdropper BE monitors the information sent by the base station BS; the single-antenna satellite user SU has K satellites in total in the visible range, and the single-antenna satellite user SU can only be served by a single scheduled satellite in one time slot.
3. The safe transmission method based on satellite opportunistic scheduling combined beamforming according to claim 1, wherein in the resolving process, a satellite downlink channel is obtained according to the fact that all links in the cognitive low-earth-orbit satellite network are static slow fading channels and the channels between different beams of the same satellite are independent, and the channel coefficient h of the ground link is Rayleigh distribution.
4. The safe transmission method based on satellite opportunistic scheduling combined beamforming according to claim 1, wherein the received signal-to-noise ratios at SU, SE, BU, and BE are calculated from the received signals at SU, SE, BU, and BE and the beamforming vectors at satellite and BS, thereby obtaining the safe rates at SU and BU; the safe energy efficiency is the safe bit number which can be reached by unit energy and bandwidth in signal transmission, and the safe energy efficiency eta at SUskComprises the following steps:
ηsk＝Csk/(||w||2+Pck+||v||2+Pb)
wherein the content of the first and second substances,
Figure FDA0003389691570000021
and
Figure FDA0003389691570000024
representing the beamforming vectors, C, at the satellite and BS, respectivelyskIs a safe rate at SU, PckAnd PbRespectively represent the constant independent transmission power of the satellite and the base station, and k is the serial number of the satellite.
5. The method for secure transmission based on joint beamforming for opportunistic scheduling of satellites according to claim 1, wherein the optimization problem of maximizing the safe energy efficiency achievable by the satellite users is:
Figure FDA0003389691570000022
s.t.CTB≥Γb (5a)
CTγs≥Λs (5b)
CTγb≥Λb (5c)
||w||2≤PS (5d)
||v||2≤PB (5e)
Figure FDA0003389691570000023
wherein, C ═ C1,c2...cK]TA scheduling vector representing the satellite, η ═ ηs1,ηs2...ηsk]TAn available SEE vector representing SU, B ═ Cb1,Cb2...Cbk]TSR vector, gamma, representing BUs＝[γs1,γs2...γsk]TAnd gammab＝[γb1,γb2...γbk]TSINR vectors, Γ, representing SU and BU, respectivelybMinimum SR threshold, Λ, indicating that BU safe transmission is satisfiedsAnd ΛbIndividual watchMinimum SINR requirement, P, of SU and BUSAnd PBRepresenting the maximum transmission power of the satellite and the base station, respectively, the constraint (5f) ensuring that there is and only one satellite scheduled in a time slot, ck1 indicates that the kth satellite is scheduled to transmit a signal to SU.
6. The secure transmission method based on satellite opportunistic scheduling combined beamforming according to claim 5, wherein the satellite scheduling vector C in the fixed problem reduces the optimization problem to the following convex optimization problem:
Figure FDA0003389691570000031
Figure FDA0003389691570000032
Figure FDA0003389691570000033
Figure FDA0003389691570000034
Tr(W)≤PS,W≥0 (10d)
Tr(V)≤PB,V≥0 (10e)
and (5) solving by using a mathematical tool until the change value of the optimization target in the step (10) is not more than the minimum error epsilon or the iteration times reach the maximum, and obtaining a satellite scheduling vector and beam forming vectors of the satellite and the BS.
7. The secure transmission method based on satellite opportunistic scheduling combined beamforming according to claim 6, wherein the optimal satellite scheduling vector and beamforming vectors of the satellite and the BS are solved by three layers of iterative processes, namely main loop, outer loop and inner loop;
where main searches for the best satellite scheduling vector C in a round-robin fashion*(ii) a Fixing a satellite scheduling vector C in a main cycle and calling an outer cycle to calculate the obtainable maximum safe energy efficiency value corresponding to the satellite scheduling vector C, and finally obtaining the optimal satellite scheduling vector C which enables the optimization target to be maximum by traversing all values of the satellite scheduling vector C*；
Maximum safe energy efficiency η obtainable by SU at given satellite scheduling vector C calculated by outer loopspInitializing the maximum number of iterations imaxMinimum tolerance error ε, current iteration number i and
Figure FDA0003389691570000035
then calling an internal cyclic utilization D.C. approximation method to obtain a given value
Figure FDA0003389691570000036
Time optimal matrix
Figure FDA0003389691570000037
And accordingly pair
Figure FDA0003389691570000038
Updating is carried out until
Figure FDA0003389691570000039
The change value of the energy efficiency is less than epsilon or the current iteration times reach the maximum, so that the optimal safe energy efficiency value is obtained;
inner loop calculation given
Figure FDA00033896915700000310
Time optimal matrix
Figure FDA00033896915700000311
The inner loop first initializes the maximum number of iterations jmaxMinimum tolerance error, epsilon, initial matrix
Figure FDA00033896915700000312
Optimization objective f0With the current number of iterations j, so that
Figure FDA00033896915700000313
Then solving the problem (10) to obtain
Figure FDA0003389691570000041
According to
Figure FDA0003389691570000042
To fj+1Updating until fjThe variation value of (a) is less than epsilon or the current iteration number reaches the maximum, thereby obtaining the optimal matrix
Figure FDA0003389691570000043
8. A safe transmission system based on satellite opportunistic scheduling and combined beam forming is characterized by comprising a safe energy efficiency solving module, an optimization problem constructing module and an optimization problem solving module;
the safe energy efficiency solving module is based on a cognitive low-orbit satellite-ground network system; calculating the received signal-to-interference-and-noise ratio of the receiving signals at each receiving node, and calculating the safe speed of the satellite user and the base station user and the safe energy efficiency of the satellite user;
the safety rate of base station users in the cognitive low-orbit satellite-ground network is not less than the minimum safety rate gammabThe signal-to-interference-and-noise ratio of the satellite user and the base station user is not less than the threshold value lambdasAnd ΛbAnd maximum transmission power P of satellite and base stationSAnd PBThe limitation is used as a constraint condition, and an optimization problem that the satellite user can achieve the maximum safe energy efficiency is established;
the optimization problem solving module fixes satellite scheduling vectors, converts non-convex optimization problems into convex optimization problems by utilizing a Dinkelbach algorithm and a D.C. approximation method, solves the convex optimization problems to obtain beam forming vectors of the satellite and the base station, obtains an optimal solution through traversal search of the satellite scheduling vectors, and takes the optimal solution as a basis for beam forming of the base station and the scheduled satellite and data transmission completion.
9. A computer device comprising a processor and a memory, wherein the memory is used for storing a computer executable program, the processor reads the computer executable program from the memory and executes the computer executable program, and the processor can realize the safe transmission method based on satellite opportunity scheduling combined beamforming according to any one of claims 1 to 7 when executing the computer executable program.
10. A computer readable storage medium, having stored thereon a computer program which, when being executed by a processor, is adapted to carry out the method for secure transmission based on joint beamforming for satellite opportunistic scheduling as claimed in any one of the claims 1 to 7.
CN202111464234.8A 2021-12-02 2021-12-02 Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming Pending CN114172551A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111464234.8A CN114172551A (en) 2021-12-02 2021-12-02 Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111464234.8A CN114172551A (en) 2021-12-02 2021-12-02 Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming

Publications (1)

Publication Number Publication Date
CN114172551A true CN114172551A (en) 2022-03-11

Family

ID=80482688

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111464234.8A Pending CN114172551A (en) 2021-12-02 2021-12-02 Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming

Country Status (1)

Country Link
CN (1) CN114172551A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114978387A (en) * 2022-05-09 2022-08-30 上海科技大学 Wireless aerial computing method based on low-earth-orbit satellite network

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130017855A1 (en) * 2011-07-15 2013-01-17 Telefonaktiebolaget Lm Ericsson (Publ) Distributed beam selection for cellular communication
CN107888270A (en) * 2017-12-25 2018-04-06 北京理工大学 Recognize the safe transmission method of physical layer in satellite ground UNE
CN111447631A (en) * 2020-03-05 2020-07-24 南京邮电大学 Satellite-ground combined beam forming and power distribution method based on non-orthogonal multiple access technology
CN112290995A (en) * 2020-11-06 2021-01-29 郑州大学 Beam design method based on safety energy efficiency in satellite-ground integrated network
CN113114343A (en) * 2021-04-08 2021-07-13 东南大学 High-energy-efficiency intelligent dynamic beam forming method for multi-beam satellite
CN113644952A (en) * 2021-05-09 2021-11-12 中国电子科技集团公司第五十四研究所 Multi-measurement and control station multi-satellite MIMO uplink anti-interference method based on distributed CSI

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130017855A1 (en) * 2011-07-15 2013-01-17 Telefonaktiebolaget Lm Ericsson (Publ) Distributed beam selection for cellular communication
CN107888270A (en) * 2017-12-25 2018-04-06 北京理工大学 Recognize the safe transmission method of physical layer in satellite ground UNE
CN111447631A (en) * 2020-03-05 2020-07-24 南京邮电大学 Satellite-ground combined beam forming and power distribution method based on non-orthogonal multiple access technology
CN112290995A (en) * 2020-11-06 2021-01-29 郑州大学 Beam design method based on safety energy efficiency in satellite-ground integrated network
CN113114343A (en) * 2021-04-08 2021-07-13 东南大学 High-energy-efficiency intelligent dynamic beam forming method for multi-beam satellite
CN113644952A (en) * 2021-05-09 2021-11-12 中国电子科技集团公司第五十四研究所 Multi-measurement and control station multi-satellite MIMO uplink anti-interference method based on distributed CSI

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
杨柳;张邦宁;郭道省;: "卫星通信系统中透明转发器增益设置优化算法", 军事通信技术, no. 01 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114978387A (en) * 2022-05-09 2022-08-30 上海科技大学 Wireless aerial computing method based on low-earth-orbit satellite network
CN114978387B (en) * 2022-05-09 2023-09-26 上海科技大学 Wireless air computing method based on low orbit satellite network

Similar Documents

Publication Publication Date Title
Zhang et al. Intelligent omni-surfaces: Ubiquitous wireless transmission by reflective-refractive metasurfaces
Gu et al. Dynamic cooperative spectrum sharing in a multi-beam LEO-GEO co-existing satellite system
Patil et al. Hybrid compression and message-sharing strategy for the downlink cloud radio-access network
CN109088659B (en) Symbol-level precoding method in multi-user downlink CoMP
Jiao et al. Intelligent hybrid nonorthogonal multiple access relaying for vehicular networks in 6G
Wang et al. Energy efficiency optimization in IRS-enhanced mmWave systems with lens antenna array
Khan et al. Rate splitting multiple access for cognitive radio GEO-LEO co-existing satellite networks
Kisseleff et al. A new optimization tool for mega-constellation design and its application to trunking systems [International Communications Satellite Systems Conference]
Zhao et al. Beamforming design for IRS-assisted uplink cognitive satellite-terrestrial networks with NOMA
CN114172551A (en) Safe transmission method and system based on satellite opportunistic scheduling and combined beamforming
Adhikary et al. A Deep Learning Approach for Target-oriented Communication Resource Allocation in Holographic MIMO
Nouri et al. Hybrid precoding based on active learning for mmWave massive MIMO communication systems
Zhang et al. Content-aware transmission in UAV-assisted multicast communication
Xu et al. Sum Secrecy Rate Maximization for IRS-aided Multi-Cluster MIMO-NOMA Terahertz Systems
Lyu et al. Hybrid noma assisted integrated sensing and communication via ris
Zhu et al. Distributed resource optimization for NOMA transmission in beamforming SATCOM
Zhang et al. SWIPT in mixed near-and far-field channels: Joint beam scheduling and power allocation
Lim et al. Joint user clustering, beamforming, and power allocation for mmWave-NOMA with imperfect SIC
Shen et al. Chance-constrained robust beamforming for multi-cell coordinated downlink
Wang et al. Multi-objective robust beamforming for integrated satellite and aerial networks supporting heterogeneous services
Lim et al. Low Complexity Joint User Association, Beamforming and RIS Reflection Optimization for Load Balancing in a Multi-RIS Assisted Network
Zhao et al. Combined UAV positioning with robust beamforming and IRS-enhanced NOMA transmission in cognitive UAV networks
Zhou et al. Power optimization for aerial intelligent reflecting surface-aided cell-free massive MIMO-based wireless sensor network
Ni et al. Joint user scheduling and hybrid beamforming design for cooperative mmWave networks
Zhao et al. Angular Information Based Robust Downlink Transmission for IRS-Enhanced Cognitive Satellite-Aerial Networks

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination