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: "path loss beamforming gain and time dynamics measurements at 28 ghz for 90 indoor coverage"
  Abstract: Achieving adequate coverage with high gain antennas is key to realizing the full promise of the wide bandwidth available at mm/cm bands. We report extensive indoor measurements at 28 GHz, with over 1000 links with and without Line-of-Sight (LOS) using a specialized narrowband channel sounder, capable of reliable measurements up to 171 dB path loss to characterize 90% coverage. Azimuthal power spectra were captured with 1-deg granularity using a 10-deg receive horn spun at speeds up to 300 rpm. Measured path gain-distance dependence in LOS and NLOS are well represented by power-law models, with 3.1 dB standard deviation in NLOS, and by a mode-diffusion model with 3.5 dB RMS error. Excess loss at 28 GHz suffered in turning a corner or into a room was found to be 30 and 32 dB respectively, in contrast to 20 dB found previously at 2 GHz. Degradation of azimuthal gain by scattering was within 4 dB in the hallway and 7 dB inside a room with 90% probability. System simulations in a canonical building indicate that every hallway needs an access point to provide 1 Gbps rate in 90% of locations using 1 GHz of bandwidth. For stationary terminals, with temporal fading caused by pedestrians, long term average-power-based aiming was within 3.7 dB of rapid beam switching in 90% of high traffic locations.

Connected through hyperedge HE-1 (induced by source paper "suburban fixed wireless access channel measurements and models at 28 ghz for 90 outdoor coverage"):
  with members:
    - "suburban residential building penetration loss at 28 ghz for fixed wireless access"
    - "28 ghz microcell measurement campaign for residential environment"
    - "how much spectrum is too much in millimeter wave wireless access"
    - "small scale local area and transitional millimeter wave propagation for 5g communications"
    - "overview of millimeter wave communications for fifth generation 5g wireless networks with a focus on propagation models"
    - "gbps user rates using mmwave relayed backhaul with high gain antennas"
    - "stationarity region of mm wave channel based on outdoor microcellular measurements at 28 ghz"
    - "5g 3gpp like channel models for outdoor urban microcellular and macrocellular environments"

Connected through hyperedge HE-2 (induced by source paper "matching in the air optimal analog beamforming under angular spread"):
  with members:
    - "suburban fixed wireless access channel measurements and models at 28 ghz for 90 outdoor coverage"
    - "how much spectrum is too much in millimeter wave wireless access"
    - "small scale local area and transitional millimeter wave propagation for 5g communications"
    - "overview of millimeter wave communications for fifth generation 5g wireless networks with a focus on propagation models"
    - "gbps user rates using mmwave relayed backhaul with high gain antennas"
    - "5g 3gpp like channel models for outdoor urban microcellular and macrocellular environments"

Connected through hyperedge HE-3 (induced by source paper "beamforming learning for mmwave communication theory and experimental validation"):
  with members:
    - "hierarchical codebook design for beamforming training in millimeter wave communication"
    - "codebook design for millimeter wave channel estimation with hybrid precoding structure"
    - "spatially sparse precoding in millimeter wave mimo systems"

Connected through hyperedge HE-4 (induced by source paper "suburban residential building penetration loss at 28 ghz for fixed wireless access"):
  with members:
    - "outdoor to indoor penetration loss at 28 ghz for fixed wireless access"
    - "overview of millimeter wave communications for fifth generation 5g wireless networks with a focus on propagation models"
    - "5g 3gpp like channel models for outdoor urban microcellular and macrocellular environments"

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)