The space-air-ground integrated network(SAGIN)is an important sixth-generation(6G)scenario that is enabled by dynamic spot beam forming by a phased array antenna(PAA).The extremely high mobility of satellites and more...The space-air-ground integrated network(SAGIN)is an important sixth-generation(6G)scenario that is enabled by dynamic spot beam forming by a phased array antenna(PAA).The extremely high mobility of satellites and more complicated radio resource control(RRC)have brought introduced a new challenge,and the issue of determining appropriate moments and procedures for executing handover(HO)for all users in a coverage area is urgent.The existing research considers the users as an entirety,and it determines the HO moment under the assumption that all of the satellite subpoints(SSP)pass through the centre of the cell.However,when using this scheme,the HO failure ratio(HOFR)would experience great degradation caused by the imbalance between the unified HO moments and the uncertain spatial distribution of users’(SDU)spatial-temporal variation.This paper proposes a novel HO moment determination method for a low-orbit satellite internet network(LEO-SIN).The rules of SDU variance under SSP motion are first proposed,and they calculate dynamic UE requests within the constraints of the footprint boundary and with SSP motions.Then,we first formulate the problems of multiuser-directed graphs for HO moment determination and prove that it is a nondeterministic polynomial-time(NP)hard problem.An animal survival algorithm based on the Dingo of algorithm(DOA)is proposed to solve the above problems.Multiuser fused directed graphs are first designed to determine HO moments based on the rules of SDU variation and the animal survival algorithm.The simulations show that the proposed method has a better HO performance for LEO-SIN.展开更多
基金supported by the China National Key Research and Development Plan(2022YFB2902605)the Beijing Natural Science Foundation(4252008)+2 种基金the 13th 5-Year Plan Civil Aerospace Technology Advance Research Project(D030301)the Hebei Province High-level Talent Funding Project(B2021003032)the New Technology Research University Cooperation Project(SKX212010010).
文摘The space-air-ground integrated network(SAGIN)is an important sixth-generation(6G)scenario that is enabled by dynamic spot beam forming by a phased array antenna(PAA).The extremely high mobility of satellites and more complicated radio resource control(RRC)have brought introduced a new challenge,and the issue of determining appropriate moments and procedures for executing handover(HO)for all users in a coverage area is urgent.The existing research considers the users as an entirety,and it determines the HO moment under the assumption that all of the satellite subpoints(SSP)pass through the centre of the cell.However,when using this scheme,the HO failure ratio(HOFR)would experience great degradation caused by the imbalance between the unified HO moments and the uncertain spatial distribution of users’(SDU)spatial-temporal variation.This paper proposes a novel HO moment determination method for a low-orbit satellite internet network(LEO-SIN).The rules of SDU variance under SSP motion are first proposed,and they calculate dynamic UE requests within the constraints of the footprint boundary and with SSP motions.Then,we first formulate the problems of multiuser-directed graphs for HO moment determination and prove that it is a nondeterministic polynomial-time(NP)hard problem.An animal survival algorithm based on the Dingo of algorithm(DOA)is proposed to solve the above problems.Multiuser fused directed graphs are first designed to determine HO moments based on the rules of SDU variation and the animal survival algorithm.The simulations show that the proposed method has a better HO performance for LEO-SIN.
