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: "massive mimo how many antennas do we need"
  Abstract: We consider a multicell MIMO uplink channel where each base station (BS) is equipped with a large number of antennas N. The BSs are assumed to estimate their channels based on pilot sequences sent by the user terminals (UTs). Recent work has shown that, as N grows infinitely large, (i) the simplest form of user detection, i.e., the matched filter (MF), becomes optimal, (ii) the transmit power per UT can be made arbitrarily small, (iii) the system performance is limited by pilot contamination. The aim of this paper is to assess to which extent the above conclusions hold true for large, but finite N. In particular, we derive how many antennas per UT are needed to achieve \eta % of the ultimate performance. We then study how much can be gained through more sophisticated minimum-mean-square-error (MMSE) detection and how many more antennas are needed with the MF to achieve the same performance. Our analysis relies on novel results from random matrix theory which allow us to derive tight approximations of achievable rates with a class of linear receivers.

Connected through hyperedge HE-1 (induced by source paper "decentralized equalization with feedforward architectures for massive mu mimo"):
  with members:
    - "gaussian message passing for overloaded massive mimo noma"
    - "feedforward architectures for decentralized precoding in massive mu mimo systems"
    - "efficient dsp and circuit architectures for massive mimo state of the art and future directions"
    - "decentralized baseband processing for massive mu mimo systems"
    - "optimally tuned nonparametric linear equalization for massive mu mimo systems"
    - "on the achievable rates of decentralized equalization in massive mu mimo systems"
    - "on the performance of mismatched data detection in large mimo systems"
    - "performance trade offs in multi processor approximate message passing"

Connected through hyperedge HE-2 (induced by source paper "optimal link scheduling in millimeter wave multi hop networks with mu mimo radios"):
  with members:
    - "integrated access and backhaul in 5g mmwave networks potentials and challenges"
    - "distributed path selection strategies for integrated access and backhaul at mmwaves"
    - "hierarchical codebook design for beamforming training in millimeter wave communication"
    - "understanding noise and interference regimes in 5g millimeter wave cellular networks"
    - "codebook design for millimeter wave channel estimation with hybrid precoding structure"
    - "hybrid architectures with few bit adc receivers achievable rates and energy rate tradeoffs"
    - "towards an appropriate receiver beamforming scheme for millimeter wave communication a power consumption based comparison"
    - "massive mimo ten myths and one critical question"

Connected through hyperedge HE-3 (induced by source paper "optimal data detection in large mimo"):
  with members:
    - "on the performance of mismatched data detection in large mimo systems"
    - "precise error analysis of regularized m estimators in high dimensions"
    - "ber analysis of the box relaxation for bpsk signal recovery"
    - "compressive phase retrieval via generalized approximate message passing"
    - "does ell_p minimization outperform ell_1 minimization"
    - "large scale mimo detection for 3gpp lte algorithms and fpga implementations"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"

Connected through hyperedge HE-4 (induced by source paper "technical report on optimal link scheduling in millimeter wave multi hop networks with space division multiple access and multiplexing"):
  with members:
    - "hybrid architectures with few bit adc receivers achievable rates and energy rate tradeoffs"
    - "towards an appropriate receiver beamforming scheme for millimeter wave communication a power consumption based comparison"
    - "massive mimo ten myths and one critical question"
    - "low power analog to digital conversion in millimeter wave systems impact of resolution and bandwidth on performance"
    - "dynamic time domain duplexing for self backhauled millimeter wave cellular networks"
    - "directional cell discovery in millimeter wave cellular networks"
    - "improving third party relaying for lte a a realistic simulation approach"
    - "millimeter wave cellular wireless networks potentials and challenges"

Connected through hyperedge HE-5 (induced by source paper "vlsi design of a nonparametric equalizer for massive mu mimo"):
  with members:
    - "1 bit massive mu mimo precoding in vlsi"
    - "optimally tuned nonparametric linear equalization for massive mu mimo systems"
    - "on the performance of mismatched data detection in large mimo systems"
    - "data detection in large multi antenna wireless systems via approximate semidefinite relaxation"
    - "large scale mimo detection for 3gpp lte algorithms and fpga implementations"
    - "massive mimo systems with non ideal hardware energy efficiency estimation and capacity limits"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"

Connected through hyperedge HE-6 (induced by source paper "antenna arrays for line of sight massive mimo half wavelength is not enough"):
  with members:
    - "massive mimo ten myths and one critical question"
    - "space constrained massive mimo hitting the wall of favorable propagation"
    - "massive mimo performance evaluation based on measured propagation data"
    - "aspects of favorable propagation in massive mimo"
    - "massive mimo for next generation wireless systems"
    - "optimal design of energy efficient multi user mimo systems is massive mimo the answer"
    - "five disruptive technology directions for 5g"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-7 (induced by source paper "on the achievable rates of decentralized equalization in massive mu mimo systems"):
  with members:
    - "on the performance of mismatched data detection in large mimo systems"
    - "performance trade offs in multi processor approximate message passing"
    - "optimality of large mimo detection via approximate message passing"
    - "system architecture and key technologies for 5g heterogeneous cloud radio access networks"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"
    - "the dynamics of message passing on dense graphs with applications to compressed sensing"
    - "estimation in gaussian noise properties of the minimum mean square error"

Connected through hyperedge HE-8 (induced by source paper "a survey on legacy and emerging technologies for public safety communications"):
  with members:
    - "survey of important issues in uav communication networks"
    - "28 ghz and 73 ghz millimeter wave indoor propagation measurements and path loss models"
    - "massive mimo for next generation wireless systems"
    - "cognitive and energy harvesting based d2d communication in cellular networks stochastic geometry modeling and analysis"
    - "what will 5g be"
    - "incentivizing spectrum sharing via subsidy regulations"
    - "millimeter wave channel modeling and cellular capacity evaluation"
    - "internet of things iot a vision architectural elements and future directions"

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)