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: "mutual information of iid complex gaussian signals on block rayleigh faded channels"
  Abstract: We present a method to compute, quickly and efficiently, the mutual information achieved by an IID (independent identically distributed) complex Gaussian input on a block Rayleigh-faded channel without side information at the receiver. The method accommodates both scalar and MIMO (multiple-input multiple-output) settings. Operationally, the mutual information thus computed represents the highest spectral efficiency that can be attained using standard Gaussian codebooks. Examples are provided that illustrate the loss in spectral efficiency caused by fast fading and how that loss is amplified by the use of multiple transmit antennas. These examples are further enriched by comparisons with the channel capacity under perfect channel-state information at the receiver, and with the spectral efficiency attained by pilot-based transmission.

Connected through hyperedge HE-1 (induced by source paper "optimal discrete spatial compression for beamspace massive mimo signals"):
  with members:
    - "a real time millimeter wave phased array mimo channel sounder"
    - "branch and bound precoding for multiuser mimo systems with 1 bit quantization"
    - "spatio temporal waveform design for multiuser massive mimo downlink with 1 bit receivers"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "cost effective millimeter wave communications with lens antenna array"
    - "fronthaul compression and transmit beamforming optimization for multi antenna uplink c ran"
    - "quantized precoding for massive mu mimo"
    - "hybrid beamforming for massive mimo a survey"

Connected through hyperedge HE-2 (induced by source paper "on the spectral efficiency of noncooperative uplink massive mimo systems"):
  with members:
    - "massive mimo ten myths and one critical question"
    - "optimal user cell association for massive mimo wireless networks"
    - "massive mimo for maximal spectral efficiency how many users and pilots should be allocated"
    - "large system analysis of correlated mimo multiple access channels with arbitrary signaling in the presence of interference"
    - "on the capacity of large mimo block fading channels"
    - "pilot contamination and precoding in multi cell tdd systems"

Connected through hyperedge HE-3 (induced by source paper "massive mimo performance tdd versus fdd what do measurements say"):
  with members:
    - "performance characterization of a real time massive mimo system with los mobile channels"
    - "overview of full dimension mimo in lte advanced pro"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "on the number of rf chains and phase shifters and scheduling design with hybrid analog digital beamforming"
    - "hybrid digital and analog beamforming design for large scale antenna arrays"
    - "no downlink pilots are needed in tdd massive mimo"
    - "massive mimo ten myths and one critical question"
    - "reciprocity calibration for massive mimo proposal modeling and validation"

Connected through hyperedge HE-4 (induced by source paper "joint user scheduling and beam selection optimization for beam based massive mimo downlinks"):
  with members:
    - "a real time millimeter wave phased array mimo channel sounder"
    - "bdma for millimeter wave terahertz massive mimo transmission with per beam synchronization"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "hybrid beamforming for massive mimo a survey"
    - "achievable rates of fdd massive mimo systems with spatial channel correlation"
    - "dynamic channel acquisition in mu mimo"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "massive mimo for next generation wireless systems"

Connected through hyperedge HE-5 (induced by source paper "one bit massive mimo channel estimation and high order modulations"):
  with members:
    - "capacity analysis of one bit quantized mimo systems with transmitter channel state information"
    - "joint channel and data estimation for large mimo systems with low precision adcs"
    - "finite snr bounds on the sum rate capacity of rayleigh block fading multiple access channels with no a priori csi"
    - "massive mimo with 1 bit adc"
    - "at low snr asymmetric quantizers are better"
    - "on the gain of joint processing of pilot and data symbols in stationary rayleigh fading channels"
    - "increased capacity per unit cost by oversampling"
    - "what is the value of joint processing of pilots and data in block fading channels"

Connected through hyperedge HE-6 (induced by source paper "finite snr bounds on the sum rate capacity of rayleigh block fading multiple access channels with no a priori csi"):
  with members:
    - "closed form output statistics of mimo block fading channels"
    - "diversity versus channel knowledge at finite block length"
    - "on the capacity of large mimo block fading channels"
    - "on the capacity of doubly correlated mimo channels"

Connected through hyperedge HE-7 (induced by source paper "closed form output statistics of mimo block fading channels"):
  with members:
    - "on the capacity of large mimo block fading channels"
    - "on the capacity of doubly correlated mimo channels"

Connected through hyperedge HE-8 (induced by source paper "objective information theory a sextuple model and 9 kinds of metrics"):
  with members:
    - "conditional entropy based user selection for multiuser mimo systems"
    - "universal and composite hypothesis testing via mismatched divergence"
    - "information inequalities for joint distributions with interpretations and applications"

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)