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: "adaptive multicell 3d beamforming in multi antenna cellular networks"
  Abstract: We consider a cellular network with multi-antenna base stations (BSs) and single-antenna users, multicell cooperation, imperfect channel state information, and directional antennas each with a vertically adjustable beam. We investigate the impact of the elevation angle of the BS antenna pattern, denoted as tilt, on the performance of the considered network when employing either a conventional single-cell transmission or a fully cooperative multicell transmission. Using the results of this investigation, we propose a novel hybrid multicell cooperation technique in which the intercell interference is controlled via either cooperative beamforming in the horizontal plane or coordinated beamfroming in the vertical plane of the wireless channel, denoted as adaptive multicell 3D beamforming. The main idea is to divide the coverage area into two disjoint vertical regions and adapt the multicell cooperation strategy at the BSs when serving each region. A fair scheduler is used to share the time-slots between the vertical regions. It is shown that the proposed technique can achieve performance comparable to that of a fully cooperative transmission but with a significantly lower complexity and signaling requirements. To make the performance analysis computationally efficient, analytical expressions for the user ergodic rates under different beamforming strategies are also derived.

Connected through hyperedge HE-1 (induced by source paper "stochastic modeling and analysis of user centric network mimo systems"):
  with members:
    - "a stochastic analysis of network mimo systems"
    - "user centric intercell interference nulling for downlink small cell networks"
    - "a tractable model for noncoherent joint transmission base station cooperation"
    - "sparse beamforming and user centric clustering for downlink cloud radio access network"
    - "location aware cross tier coordinated multipoint transmission in two tier cellular networks"
    - "analytical modeling of uplink cellular networks"
    - "network mimo with linear zero forcing beamforming large system analysis impact of channel estimation and reduced complexity scheduling"
    - "achieving massive mimo spectral efficiency with a not so large number of antennas"

Connected through hyperedge HE-2 (induced by source paper "joint tilt angle adaptation and beamforming in multicell multiuser cellular networks"):
  with members:
    - "what will 5g be"
    - "direction of arrival estimation for temporally correlated narrowband signals"

Connected through hyperedge HE-3 (induced by source paper "a stochastic analysis of network mimo systems"):
  with members:
    - "large scale mimo versus network mimo for multicell interference mitigation"
    - "a tractable model for noncoherent joint transmission base station cooperation"
    - "optimizing multi cell massive mimo for spectral efficiency how many users should be scheduled"
    - "analysis of joint transmit receive diversity in downlink mimo heterogeneous cellular networks"
    - "a stochastic geometry analysis of inter cell interference coordination and intra cell diversity"
    - "downlink mimo hetnets modeling ordering results and performance analysis"
    - "downlink multi antenna heterogeneous cellular network with load balancing"
    - "network mimo with linear zero forcing beamforming large system analysis impact of channel estimation and reduced complexity scheduling"

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)