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: "optical adaptive precoding for visible light communications"
  Abstract: Multiple-input multiple-output (MIMO) techniques have recently demonstrated significant potentials in visible light communications (VLC), as they can overcome the modulation bandwidth limitation and provide substantial improvement in terms of spectral efficiency and link reliability. However, MIMO systems typically suffer from inter-channel interference, which causes severe degradation to the system performance. In this context, we propose a novel optical adaptive precoding (OAP) scheme for the downlink of MIMO VLC systems, which exploits the knowledge of transmitted symbols to enhance the effective signal-to-interference-plus-noise ratio. We also derive bit-error-rate expressions for the OAP under perfect and outdated channel state information (CSI). Our results demonstrate that the proposed scheme is more robust to both CSI error and channel correlation, compared to conventional channel inversion precoding.

Connected through hyperedge HE-1 (induced by source paper "hybrid lifi and wifi networks a survey"):
  with members:
    - "modeling the random orientation of mobile devices measurement analysis and lifi use case"
    - "impact of device orientation on error performance of lifi systems"
    - "bidirectional user throughput maximization based on feedback reduction in lifi networks"
    - "ieee 802 11ax high efficiency wlans"
    - "handover management in 5g and beyond a topology aware skipping approach"
    - "an overview of load balancing in hetnets old myths and open problems"
    - "on the accuracy of the wyner model in cellular networks"
    - "fundamental limits of wideband localization part i a general framework"

Connected through hyperedge HE-2 (induced by source paper "on optimizing vlc networks for downlink multi user transmission a survey"):
  with members:
    - "modeling the random orientation of mobile devices measurement analysis and lifi use case"
    - "non orthogonal multiple access for mobile vlc networks with random receiver orientation"
    - "a comparative survey of optical wireless technologies architectures and applications"
    - "dc bias and power allocation in cooperative vlc networks for joint information and energy transfer"
    - "securing visible light communication systems by beamforming in the presence of randomly distributed eavesdroppers"
    - "link selection in hybrid rf vlc systems under statistical queueing constraints"
    - "multi element vlc networks led assignment power control and optimum combining"
    - "optical non orthogonal multiple access for visible light communication"

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)