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: "auxiliary beam pair enabled aod and aoa estimation in closed loop large scale mmwave mimo systems"
  Abstract: Channel estimation is of critical importance in millimeter-wave (mmWave) multiple-input multiple-output (MIMO) systems. Due to the use of large antenna arrays, low-complexity mmWave specific channel estimation algorithms are required. In this paper, an auxiliary beam pair design is proposed to provide high-resolution estimates of the channel's angle-of-departure (AoD) and angle-of-arrival (AoA) for mmWave MIMO systems. By performing an amplitude comparison with respect to each auxiliary beam pair, a set of ratio measures that characterize the channel's AoD and AoA are obtained by the receiver. Either the best ratio measure or the estimated AoD is quantized and fed back to the transmitter via a feedback channel. The proposed technique can be incorporated into control channel design to minimize initial access delay. Though the design principles are derived assuming a high-power regime, evaluation under more realistic assumption shows that by employing the proposed method, good angle estimation performance is achieved under various signal-to-noise ratio levels and channel conditions.

Connected through hyperedge HE-1 (induced by source paper "fast accurate beam and channel tracking for two dimensional phased antenna array"):
  with members:
    - "how to mobilize mmwave a joint beam and channel tracking approach"
    - "analog beam tracking in linear antenna arrays convergence optimality and performance"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "mobile millimeter wave channel acquisition tracking and abrupt change detection"
    - "28 ghz millimeter wave ultrawideband small scale fading models in wireless channels"
    - "enabling uav cellular with millimeter wave communication potentials and approaches"
    - "hybrid beamforming for massive mimo a survey"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"

Connected through hyperedge HE-2 (induced by source paper "super fast beam and channel tracking in 2d phased antenna arrays"):
  with members:
    - "how to mobilize mmwave a joint beam and channel tracking approach"
    - "analog beam tracking in linear antenna arrays convergence optimality and performance"
    - "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"
    - "compressed sensing based multi user millimeter wave systems how many measurements are needed"

Connected through hyperedge HE-3 (induced by source paper "two dimensional aod and aoa acquisition for wideband millimeter wave systems with dual polarized mimo"):
  with members:
    - "channel estimation for millimeter wave massive mimo with hybrid precoding over frequency selective fading channels"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "channel estimation for hybrid architecture based wideband millimeter wave systems"
    - "low rank tensor decomposition aided channel estimation for millimeter wave mimo ofdm systems"
    - "frequency selective hybrid precoding for limited feedback millimeter wave systems"
    - "hybrid mimo architectures for millimeter wave communications phase shifters or switches"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "adaptive millimeter wave beam alignment for dual polarized mimo systems"

Connected through hyperedge HE-4 (induced by source paper "channel estimation for hybrid architecture based wideband millimeter wave systems"):
  with members:
    - "fast channel estimation for millimetre wave wireless systems using overlapped beam patterns"
    - "channel estimation for millimeter wave massive mimo with hybrid precoding over frequency selective fading channels"
    - "structured compressive sensing based spatio temporal joint channel estimation for fdd massive mimo"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "subspace estimation and decomposition for large millimeter wave mimo systems"
    - "frequency selective hybrid precoding for limited feedback millimeter wave systems"
    - "compressed sensing based multi user millimeter wave systems how many measurements are needed"
    - "hybrid mimo architectures for millimeter wave communications phase shifters or switches"

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)