human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "on secrecy performance of antenna selection aided mimo systems against eavesdropping"
  Abstract: In this paper, the authors consider a multiple-input–multiple-output (MIMO) system consisting of one source, one destination, and one eavesdropper, where each node is equipped with an arbitrary number of antennas. To improve the security of source-destination transmissions, the authors investigate the antenna selection at the source and propose the optimal antenna selection (OAS) and suboptimal antenna selection (SAS) schemes, depending on whether the source node has the global channel state information (CSI) of both the main link (from source to destination) and the wiretap link (from source to eavesdropper). Moreover, the traditional space-time transmission (STT) is studied as a benchmark. The authors evaluate the secrecy performance of STT, SAS, and OAS schemes in terms of the probability of zero secrecy capacity. Furthermore, the authors examine the generalized secrecy diversity of the STT, SAS, and OAS schemes through an asymptotic analysis of the probability of zero secrecy capacity as the ratio between the average gains of the main and wiretap channels tends to infinity. This is different from the conventional secrecy diversity that assumes an infinite signal-to-noise ratio (SNR) received at the destination under the condition that the eavesdropper has a finite received SNR. It is shown that the generalized secrecy diversity orders of the STT, SAS, and OAS schemes are the product of the number of antennas at source and destination. Additionally, numerical results show that the proposed OAS scheme strictly outperforms both the STT and the SAS schemes in terms of the probability of zero secrecy capacity.

Connected through hyperedge HE-1 (induced by source paper "robustness of low complexity massive mimo architectures against passive eavesdropping"):
  with members:
    - "papr limited precoding in massive mimo systems with reflect and transmit array antennas"
    - "on robustness of massive mimo systems against passive eavesdropping under antenna selection"
    - "glse precoders for massive mimo systems analysis and applications"
    - "stepwise transmit antenna selection in downlink massive multiuser mimo"
    - "scalable and energy efficient millimeter massive mimo architectures reflect array and transmit array antennas"
    - "optimal transmit antenna selection for massive mimo wiretap channels"
    - "asymptotics of nonlinear lse precoders with applications to transmit antenna selection"
    - "asymptotics of transmit antenna selection impact of multiple receive antennas"

Connected through hyperedge HE-2 (induced by source paper "secrecy outage and diversity analysis of multiple cooperative source destination pairs"):
  with members:
    - "modulation and multiple access for 5g networks"
    - "physical layer security in heterogeneous networks with jammer selection and full duplex users"
    - "physical layer security for spectrum sharing systems"
    - "artificial noise aided secure transmission in large scale spectrum sharing networks"
    - "location based beamforming for enhancing secrecy in rician wiretap channels"
    - "physical layer security in heterogeneous cellular networks"
    - "secrecy transmit beamforming for heterogeneous networks"
    - "proactive eavesdropping via cognitive jamming in fading channels"

Connected through hyperedge HE-3 (induced by source paper "optimal power allocation for minimizing outage probability of uav relay communications"):
  with members:
    - "ultra reliable uav communication using altitude and cooperation diversity"
    - "joint trajectory and communication design for multi uav enabled wireless networks"
    - "joint altitude and beamwidth optimization for uav enabled multiuser communications"
    - "uav assisted heterogeneous networks for capacity enhancement"
    - "wireless communications with unmanned aerial vehicles opportunities and challenges"

Connected through hyperedge HE-4 (induced by source paper "on robustness of massive mimo systems against passive eavesdropping under antenna selection"):
  with members:
    - "stepwise transmit antenna selection in downlink massive multiuser mimo"
    - "iterative antenna selection for secrecy enhancement in massive mimo wiretap channels"
    - "asymptotics of nonlinear lse precoders with applications to transmit antenna selection"
    - "asymptotics of transmit antenna selection impact of multiple receive antennas"
    - "asymptotic performance analysis of spatially reconfigurable antenna arrays"
    - "optimal number of transmit antennas for secrecy enhancement in massive mimome channels"
    - "secrecy and energy efficiency in massive mimo aided heterogeneous c ran a new look at interference"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"

Connected through hyperedge HE-5 (induced by source paper "optimal transmit antenna selection for massive mimo wiretap channels"):
  with members:
    - "precoding via approximate message passing with instantaneous signal constraints"
    - "asymptotics of nonlinear lse precoders with applications to transmit antenna selection"
    - "asymptotics of transmit antenna selection impact of multiple receive antennas"
    - "a survey on wireless security technical challenges recent advances and future trends"
    - "hybrid digital and analog beamforming design for large scale antenna arrays"
    - "secure massive mimo transmission with an active eavesdropper"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"
    - "energy efficient antenna selection and power allocation for large scale multiple antenna systems with hybrid energy supply"

Connected through hyperedge HE-6 (induced by source paper "secure transmit antenna selection protocol for mimo noma networks over nakagami m channels"):
  with members:
    - "secrecy outage analysis for downlink transmissions in the presence of randomly located eavesdroppers"
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "secrecy sum rate maximization in non orthogonal multiple access"
    - "enhancing the physical layer security of non orthogonal multiple access in large scale networks"
    - "harvest then cooperate wireless powered cooperative communications"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"
    - "robust beamforming for security in mimo wiretap channels with imperfect csi"

Connected through hyperedge HE-7 (induced by source paper "secrecy analysis of random mimo wireless networks over alpha mu fading channels"):
  with members:
    - "physical layer security in millimeter wave cellular networks"
    - "performance analysis for physical layer security in multi antenna downlink networks with limited csi feedback"
    - "the secrecy graph and some of its properties"
    - "a geometric interpretation of fading in wireless networks theory and applications"

Connected through hyperedge HE-8 (induced by source paper "multi antenna wireless legitimate surveillance systems design and performance analysis"):
  with members:
    - "secure massive mimo systems with limited rf chains"
    - "analysis and design of secure massive mimo systems in the presence of hardware impairments"
    - "linear precoding of data and artificial noise in secure massive mimo systems"
    - "throughput analysis and optimization of wireless powered multiple antenna full duplex relay systems"
    - "wireless information surveillance via proactive eavesdropping with spoofing relay"
    - "a survey on wireless security technical challenges recent advances and future trends"
    - "proactive eavesdropping via cognitive jamming in fading channels"
    - "improving physical layer security in wireless communications using diversity techniques"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.IT(Information Theory)