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: "new beam tracking technique for millimeter wave band communications"
  Abstract: In this paper, we propose an efficient beam tracking method for mobility scenario in mmWave-band communications. When the position of the mobile changes in mobility scenario, the base-station needs to perform beam training frequently to track the time-varying channel, thereby spending significant resources for training beams. In order to reduce the training overhead, we propose a new beam training approach called "beam tracking" which exploits the continuous nature of time varying angle of departure (AoD) for beam selection. We show that transmission of only two training beams is enough to track the time-varying AoD at good accuracy. We derive the optimal selection of beam pair which minimizes Cramer-Rao Lower Bound (CRLB) for AoD estimation averaged over statistical distribution of the AoD. Our numerical results demonstrate that the proposed beam tracking scheme produces better AoD estimation than the conventional beam training protocol with less training overhead.

Connected through hyperedge HE-1 (induced by source paper "fast analog beam tracking in phased antenna arrays theory and performance"):
  with members:
    - "how to mobilize mmwave a joint beam and channel tracking approach"
    - "communication computing and caching for mobile vr delivery modeling and trade off"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "enabling uav cellular with millimeter wave communication potentials and approaches"
    - "tracking mm wave channel dynamics fast beam training strategies under mobility"
    - "hybrid beamforming for massive mimo a survey"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"
    - "tracking angles of departure and arrival in a mobile millimeter wave channel"

Connected through hyperedge HE-2 (induced by source paper "transmitter beam selection in millimeter wave mimo with in band position aiding"):
  with members:
    - "position aided beam alignment for millimeter wave backhaul systems with large phased arrays"
    - "millimeter wave mimo channel estimation using overlapped beam patterns and rate adaptation"
    - "beampattern based tracking for millimeter wave communication systems"
    - "hierarchical codebook design for beamforming training in millimeter wave communication"
    - "millimeter wave vehicular communication to support massive automotive sensing"
    - "tracking mm wave channel dynamics fast beam training strategies under mobility"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "an esprit based approach for 2 d localization of incoherently distributed sources in massive mimo systems"

Connected through hyperedge HE-3 (induced by source paper "analog beam tracking in linear antenna arrays convergence optimality and performance"):
  with members:
    - "optimal precoders for tracking the aod and aoa of a mmwave path"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "mobile millimeter wave channel acquisition tracking and abrupt change detection"
    - "tracking mm wave channel dynamics fast beam training strategies under mobility"
    - "compressed sensing based multi user millimeter wave systems how many measurements are needed"
    - "hybrid mimo architectures for millimeter wave communications phase shifters or switches"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "massive mimo for next generation wireless systems"

Connected through hyperedge HE-4 (induced by source paper "crlb calculations for joint aoa aod and multipath gain estimation in millimeter wave wireless networks"):
  with members:
    - "tracking angles of departure and arrival in a mobile millimeter wave channel"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"

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)