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: "on clustered statistical mimo millimeter wave channel simulation"
  Abstract: The use of mmWave frequencies is one of the key strategies to achieve the fascinating 1000x increase in the capacity of future 5G wireless systems. While for traditional sub-6 GHz cellular frequencies several well-developed statistical channel models are available for system simulation, similar tools are not available for mmWave frequencies, thus preventing a fair comparison of independently developed transmission and reception schemes. In this paper we provide a simple albeit accurate statistical procedure for the generation of a clustered MIMO channel model operating at mmWaves, for both the cases of slowly and rapidly time-varying channels. Matlab scripts for channel generation are also provided, along with an example of their use.

Connected through hyperedge HE-1 (induced by source paper "subspace tracking and least squares approaches to channel estimation in millimeter wave multiuser mimo"):
  with members:
    - "massive mimo in sub 6 ghz and mmwave physical practical and use case differences"
    - "cell free and user centric massive mimo at millimeter wave frequencies"
    - "subspace tracking algorithms for millimeter wave mimo channel estimation with hybrid beamforming"
    - "millimeter wave mimo channel estimation using overlapped beam patterns and rate adaptation"
    - "low complexity massive mimo subspace estimation and tracking from low dimensional projections"
    - "enhancing the estimation of mm wave large array channels by exploiting spatio temporal correlation and sparse scattering"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "subspace estimation and decomposition for large millimeter wave mimo systems"

Connected through hyperedge HE-2 (induced by source paper "energy efficiency and asymptotic performance evaluation of beamforming structures in doubly massive mimo mmwave systems"):
  with members:
    - "doubly massive mmwave mimo systems using very large antenna arrays at both transmitter and receiver"
    - "multi user massive mimo communication systems based on irregular antenna arrays"
    - "enhancing the estimation of mm wave large array channels by exploiting spatio temporal correlation and sparse scattering"
    - "energy efficiency optimization of 5g radio frequency chain systems"
    - "hybrid digital and analog beamforming design for large scale antenna arrays"
    - "a survey of energy efficient techniques for 5g networks and challenges ahead"
    - "massive mimo combining with switches"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"

Connected through hyperedge HE-3 (induced by source paper "single carrier modulation versus ofdm for millimeter wave wireless mimo"):
  with members:
    - "are mmwave low complexity beamforming structures energy efficient analysis of the downlink mu mimo"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "subspace estimation and decomposition for large millimeter wave mimo systems"
    - "a survey of energy efficient techniques for 5g networks and challenges ahead"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "what will 5g be"
    - "spatially sparse precoding in millimeter wave mimo systems"

Connected through hyperedge HE-4 (induced by source paper "energy efficient downlink power control in mmwave cell free and user centric massive mimo"):
  with members:
    - "cell free and user centric massive mimo at millimeter wave frequencies"
    - "downlink power control in user centric and cell free massive mimo wireless networks"
    - "energy efficient power control a look at 5g wireless technologies"
    - "cell free massive mimo versus small cells"
    - "a survey of energy efficient techniques for 5g networks and challenges ahead"
    - "what will 5g be"

Connected through hyperedge HE-5 (induced by source paper "massive mimo 5g cellular networks mm wave versus mu wave frequencies"):
  with members:
    - "doubly massive mmwave mimo systems using very large antenna arrays at both transmitter and receiver"
    - "are mmwave low complexity beamforming structures energy efficient analysis of the downlink mu mimo"
    - "subspace estimation and decomposition for large millimeter wave mimo systems"
    - "spectral efficiency of mimo millimeter wave links with single carrier modulation for 5g networks"
    - "cell free massive mimo versus small cells"
    - "hybrid digital and analog beamforming design for large scale antenna arrays"
    - "hybrid mimo architectures for millimeter wave communications phase shifters or switches"
    - "massive mimo for next generation wireless systems"

Connected through hyperedge HE-6 (induced by source paper "optimal design of energy efficient millimeter wave hybrid transceivers for wireless backhaul"):
  with members:
    - "are mmwave low complexity beamforming structures energy efficient analysis of the downlink mu mimo"
    - "hybrid digital and analog beamforming design for large scale antenna arrays"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"
    - "hybrid mimo architectures for millimeter wave communications phase shifters or switches"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "coverage and rate analysis for millimeter wave cellular networks"
    - "millimeter wave cellular wireless networks potentials and challenges"
    - "spatially sparse precoding in millimeter wave mimo systems"

Connected through hyperedge HE-7 (induced by source paper "cell free and user centric massive mimo at millimeter wave frequencies"):
  with members:
    - "5g 3gpp like channel models for outdoor urban microcellular and macrocellular environments"
    - "cell free massive mimo versus small cells"
    - "cell free massive mimo uniformly great service for everyone"
    - "what will 5g be"

Connected through hyperedge HE-8 (induced by source paper "multiuser millimeter wave mimo channel estimation with hybrid beamforming"):
  with members:
    - "subspace tracking algorithms for millimeter wave mimo channel estimation with hybrid beamforming"
    - "what will 5g be"

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)