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 "energy efficient alternating iterative secure structure of maximizing secrecy rate for directional modulation networks"):
  Abstract: In a directional modulation (DM) network, the issues of security and privacy have taken on an increasingly important role. Since the power allocation of confidential message and artificial noise will make a constructive effect on the system performance, it is important to jointly consider the relationship between the beamforming vectors and the power allocation (PA) factors. To maximize the secrecy rate (SR), an alternating iterative structure (AIS) between the beamforming and PA is proposed. With only two or three iterations, it can rapidly converge to its rate ceil. Simulation results indicate that the SR performance of proposed AIS is much better than the null-space projection (NSP) based PA strategy in the medium and large signal-to-noise ratio (SNR) regions, especially when the number of antennas at the DM transmitter is small.

Includes members:
  Member "alternating iterative secure structure between beamforming and power allocation for uav aided directional modulation networks":
    also connected through other hyperedges:
      (none)
  Member "robust secure transmission of using main lobe integration based leakage beamforming in directional modulation mu mimo systems":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "optimal power allocation for secure directional modulation networks with a full duplex uav user")
  Member "secure transmission with large numbers of antennas and finite alphabet inputs":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "downlink secrecy rate of one bit massive mimo system with active eavesdropping")
  Member "artificial noise aided secure multicast precoding for directional modulation systems":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "performance analysis of directional modulation with finite quantized rf phase shifters in analog beamforming structure")
  Member "low complexity and high resolution doa estimation for hybrid analog and digital massive mimo receive array":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "optimal power allocation for secure directional modulation networks with a full duplex uav user")
  Member "artificial noise aided secure transmission with directional modulation based on random frequency diverse arrays":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "covert transmission with a self sustained relay")
  Member "optimal power allocation for artificial noise under imperfect csi against spatially random eavesdroppers":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "safeguarding decentralized wireless networks using full duplex jamming receivers")
  Member "an overview of sustainable green 5g networks":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "cross layer scheduling and beamforming in smart grid powered cellular networks with heterogeneous energy coordination")

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)