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 "on robustness of massive mimo systems against passive eavesdropping under antenna selection"):
  Abstract: In massive MIMO wiretap settings, the base station can significantly suppress eavesdroppers by narrow beamforming toward legitimate terminals. Numerical investigations show that by this approach, secrecy is obtained at no significant cost. We call this property of massive MIMO systems `secrecy for free' and show that it not only holds when all the transmit antennas at the base station are employed, but also when only a single antenna is set active. Using linear precoding, the information leakage to the eavesdroppers can be sufficiently diminished, when the total number of available transmit antennas at the base station grows large, even when only a fixed number of them are selected. This result indicates that passive eavesdropping has no significant impact on massive MIMO systems, regardless of the number of active transmit antennas.

Includes members:
  Member "stepwise transmit antenna selection in downlink massive multiuser mimo":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "robustness of low complexity massive mimo architectures against passive eavesdropping")
  Member "iterative antenna selection for secrecy enhancement in massive mimo wiretap channels":
    also connected through other hyperedges:
      (none)
  Member "asymptotics of nonlinear lse precoders with applications to transmit antenna selection":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "robustness of low complexity massive mimo architectures against passive eavesdropping")
  Member "asymptotics of transmit antenna selection impact of multiple receive antennas":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "robustness of low complexity massive mimo architectures against passive eavesdropping")
  Member "asymptotic performance analysis of spatially reconfigurable antenna arrays":
    also connected through other hyperedges:
      (none)
  Member "optimal number of transmit antennas for secrecy enhancement in massive mimome channels":
    also connected through other hyperedges:
      (none)
  Member "secrecy and energy efficiency in massive mimo aided heterogeneous c ran a new look at interference":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "robustness of low complexity massive mimo architectures against passive eavesdropping")
  Member "on secrecy performance of antenna selection aided mimo systems against eavesdropping":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "robustness of low complexity massive mimo architectures against passive eavesdropping")

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)