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: "subverting massive mimo by smart jamming"
  Abstract: We consider uplink transmission of a massive multiuser multiple-input multiple-output (MU-MIMO) system in the presence of a smart jammer. The jammer aims to degrade the sum spectral efficiency of the legitimate system by attacking both the training and data transmission phases. First, we derive a closed-form expression for the sum spectral efficiency by taking into account the presence of a smart jammer. Then, we determine how a jammer with a given energy budget should attack the training and data transmission phases to induce the maximum loss to the sum spectral efficiency. Numerical results illustrate the impact of optimal jamming specifically in the large limit of the number of base station (BS) antennas.

Connected through hyperedge HE-1 (induced by source paper "on the pilot contamination attack in multi cell multiuser massive mimo networks"):
  with members:
    - "pilot spoofing attack by multiple eavesdroppers"
    - "multiple antennas secure transmission under pilot spoofing and jamming attack"
    - "active attack on user load achieving pilot design in massive mimo networks"
    - "user load analysis and pilot sequence design for multi cell massive mimo networks"
    - "the world s first real time testbed for massive mimo design implementation and validation"
    - "multi cell multiuser massive mimo networks user capacity analysis and pilot design"
    - "massive mimo pilot retransmission strategies for robustification against jamming"
    - "power allocation schemes for multicell massive mimo systems"

Connected through hyperedge HE-2 (induced by source paper "jamming robust uplink transmission for spatially correlated massive mimo systems"):
  with members:
    - "jamming suppression in massive mimo systems"
    - "hardware distortion correlation has negligible impact on ul massive mimo spectral efficiency"
    - "cell free massive mimo networks optimal power control against active eavesdropping"
    - "multiple antennas secure transmission under pilot spoofing and jamming attack"
    - "jamming detection in massive mimo systems"
    - "secure massive mimo transmission with an active eavesdropper"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"
    - "securing massive mimo at the physical layer"

Connected through hyperedge HE-3 (induced by source paper "jam sessions analysis and experimental evaluation of advanced jamming attacks in mimo networks"):
  with members:
    - "machine learning for wireless communications in the internet of things a comprehensive survey"
    - "securing the internet of things in the age of machine learning and software defined networking"
    - "a survey on wireless security technical challenges recent advances and future trends"

Connected through hyperedge HE-4 (induced by source paper "security vulnerability of fdd massive mimo systems in downlink training phase"):
  with members:
    - "a survey of physical layer security techniques for 5g wireless networks and challenges ahead"
    - "jamming resistant receivers for the massive mimo uplink"
    - "jamming detection in massive mimo systems"
    - "joint channel training and feedback for fdd massive mimo systems"
    - "structured compressive sensing based spatio temporal joint channel estimation for fdd massive mimo"
    - "low rank covariance assisted downlink training and channel estimation for fdd massive mimo systems"
    - "secure massive mimo transmission with an active eavesdropper"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"

Connected through hyperedge HE-5 (induced by source paper "multiple antennas secure transmission under pilot spoofing and jamming attack"):
  with members:
    - "secure transmission with large numbers of antennas and finite alphabet inputs"
    - "jamming detection in massive mimo systems"
    - "linear precoding of data and artificial noise in secure massive mimo systems"
    - "physical layer security in heterogeneous cellular networks"
    - "massive mimo pilot retransmission strategies for robustification against jamming"
    - "secure massive mimo transmission with an active eavesdropper"
    - "pilot reuse for massive mimo transmission over spatially correlated rayleigh fading channels"
    - "securing massive mimo at the physical layer"

Connected through hyperedge HE-6 (induced by source paper "jamming resistant receivers for the massive mimo uplink"):
  with members:
    - "jamming resistant receivers for massive mimo"
    - "pilot contamination is not a fundamental asymptotic limitation in massive mimo"
    - "secure massive mimo transmission with an active eavesdropper"
    - "jamming aided secure communication in massive mimo rician channels"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"
    - "worst case jamming on mimo gaussian channels"
    - "securing massive mimo at the physical layer"
    - "interference reduction in multi cell massive mimo systems i large scale fading precoding and decoding"

Connected through hyperedge HE-7 (induced by source paper "jamming resistant receivers for massive mimo"):
  with members:
    - "pilot contamination is not a fundamental asymptotic limitation in massive mimo"
    - "jamming aided secure communication in massive mimo rician channels"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"
    - "securing massive mimo at the physical layer"
    - "massive mimo for maximal spectral efficiency how many users and pilots should be allocated"
    - "a coordinated approach to channel estimation in large scale multiple antenna systems"
    - "energy and spectral efficiency of very large multiuser mimo systems"

Connected through hyperedge HE-8 (induced by source paper "jamming detection in massive mimo systems"):
  with members:
    - "secure massive mimo transmission with an active eavesdropper"
    - "physical layer security for massive mimo an overview on passive eavesdropping and active attacks"
    - "securing massive mimo at the physical layer"

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)