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: "beamspace su mimo for future millimeter wave wireless communications"
  Abstract: For future networks [i.e., the fifth generation (5G) wireless networks and beyond], millimeter-wave (mmWave) communication with large available unlicensed spectrum is a promising technology that enables gigabit multimedia applications. Thanks to the short wavelength of mmWave radio, massive antenna arrays can be packed into the limited dimensions of mmWave transceivers. Therefore, with directional beamforming, both mmWave transmitters (MTXs) and mmWave receivers (MRXs) are capable of supporting multiple beams in 5G networks. However, for the transmission between an MTX and an MRX, most works have only considered a single beam, which means that they do not make full potential use of mmWave. Furthermore, the connectivity of single beam transmission can easily be blocked. In this context, we propose a single-user (SU) multi-beam concurrent transmission scheme for future mmWave networks with multiple reflected paths. Based on spatial spectrum reuse, the scheme can be described as a multiple-input multiple-output (MIMO) technique in beamspace (i.e., in the beam-number domain). Moreover, this paper investigates the challenges and potential solutions for implementing this scheme, including multi-beam selection, cooperative beam tracking, multi-beam power allocation, and synchronization. The theoretical and numerical results show that the proposed beamspace SU-MIMO can largely improve the achievable rate of the transmission between an MTX and an MRX and, meanwhile, can maintain the connectivity.

Connected through hyperedge HE-1 (induced by source paper "ieee 802 11ay based mmwave wlans design challenges and solutions"):
  with members:
    - "performance analysis of integrated sub 6 ghz millimeter wave wireless local area networks"
    - "ieee 802 11ax high efficiency wlans"
    - "initial access in 5g mmwave cellular networks"
    - "flexible dual connectivity spectrum aggregation for decoupled uplink and downlink access in 5g heterogeneous systems"
    - "joint millimeter wave and microwave resources allocation in cellular networks with dual mode base stations"
    - "reciprocity calibration for massive mimo proposal modeling and validation"
    - "beam searching and transmission scheduling in millimeter wave communications"
    - "60 ghz mac standardization progress and way forward"

Connected through hyperedge HE-2 (induced by source paper "beam management for millimeter wave beamspace mu mimo systems"):
  with members:
    - "millimeter wave beam alignment large deviations analysis and design insights"
    - "beam searching and transmission scheduling in millimeter wave communications"
    - "millimeter wave cellular networks a mac layer perspective"
    - "coverage and rate analysis for millimeter wave cellular networks"
    - "transmission capacity of ad hoc networks with spatial diversity"

Connected through hyperedge HE-3 (induced by source paper "throughput and robustness guaranteed beam tracking for mmwave wireless networks"):
  with members:
    - "beam searching and transmission scheduling in millimeter wave communications"
    - "millimeter wave cellular networks a mac layer perspective"
    - "what will 5g be"
    - "quality aware coding and relaying for 60 ghz real time wireless video broadcasting"

Connected through hyperedge HE-4 (induced by source paper "enhanced random access and beam training for mmwave wireless local networks with high user density"):
  with members:
    - "throughput and robustness guaranteed beam tracking for mmwave wireless networks"
    - "millimeter wave communications for future mobile networks"
    - "analysis of multi hop outdoor 60 ghz wireless networks with full duplex buffered relays"
    - "coding the beams improving beamforming training in mmwave communication system"

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.NI(Networking and Internet Architecture)