human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "secure communication in uplink transmissions user selection and multiuser secrecy gain"):
  Abstract: In this paper, we investigate secure communications in uplink transmissions, where there are a base station (BS) with    $M$    receive antennas,    $K$    mobile users each with a single antenna, and an eavesdropper with    $N$    receive antennas. The closed-form expressions of the achievable ergodic secrecy sum rates (ESSRs) for a random    $k$    users selection scheme in the high and low signal-to-noise ratio regimes are presented. It is shown that the scaling behavior of ESSR with respect to the number of served users    $k$    can be quite different under different system configurations, determined by the numbers of the BS antennas and that of the eavesdropper antennas. In order to achieve a multiuser gain, two low-complexity user selection schemes are proposed under different assumptions on the eavesdropper’s channel state information. The closed-form expressions of the achievable ESSRs and the multiuser secrecy gains of the two schemes are also presented in both low and high SNR regimes. We observe that, as    $k$    increases, the multiuser secrecy gain increases, while the ESSR may decrease. Therefore, when    $N$    is much larger than    $M$   , serving one user with the strongest channel (Time Division Multiple Address-like) is a favorable secrecy scheme, where the ESSR scales with    $\sqrt {2\log K}$   .

Includes members:
  Member "secure massive mimo transmission with an active eavesdropper":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "downlink secrecy rate of one bit massive mimo system with active eavesdropping")
  Member "the ergodic capacity of the multiple access channel under distributed scheduling order optimality of linear receivers":
    also connected through other hyperedges:
      (none)
  Member "exact joint distribution analysis of zero forcing v blast gains with greedy ordering":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "distributed spatial multiplexing systems with hardware impairments and imperfect channel estimation under rank 1 rician fading channels")
  Member "multiuser diversity for secrecy communications using opportunistic jammer selection secure dof and jammer scaling law":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "effective optimization criteria and relay selection algorithms for physical layer security in multiple antenna relay networks")
  Member "energy and spectral efficiency of very large multiuser mimo systems":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "downlink secrecy rate of one bit massive mimo system with active eavesdropping")
  Member "secure diversity multiplexing tradeoff of zero forcing transmit scheme at finite snr":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "joint relay selection and power allocation in large scale mimo systems with untrusted relays and passive eavesdroppers")
  Member "robust beamforming for security in mimo wiretap channels with imperfect csi":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "non orthogonal multiple access for 5g and beyond")
  Member "secure transmission with artificial noise over fading channels achievable rate and optimal power allocation":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "secure massive mimo communication with low resolution dacs")

Question: Please tell me which class the source paper 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)