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: "superimposed pilots are superior for mitigating pilot contamination in massive mimo"
  Abstract: In this paper, superimposed pilots are introduced as an alternative to time-multiplexed pilot and data symbols for mitigating pilot contamination in massive multiple-input multiple-output (MIMO) systems. We propose a non-iterative scheme for uplink channel estimation based on superimposed pilots and derive an expression for the uplink signal-to-interference-plus-noise ratio (SINR) at the output of a matched filter employing this channel estimate. Based on this expression, we observe that power control is essential when superimposed pilots are employed. Moreover, the quality of the channel estimate can be improved by reducing the interference that results from transmitting data alongside the pilots, and an intuitive iterative data-aided scheme that reduces this component of interference is also proposed. Approximate expressions for the uplink SINR are provided for the iterative data-aided method as well. In addition, we show that a hybrid system with users utilizing both time-multiplexed and superimposed pilots is superior to an optimally designed system that employs only time-multiplexed pilots, even when the non-iterative channel estimate is used to build the detector and precoder. We also describe a simple approach to implement this hybrid system by minimizing the overall inter- and intracell interference. Numerical simulations demonstrating the performance of the proposed channel estimation schemes and the superiority of the hybrid system are also provided.

Connected through hyperedge HE-1 (induced by source paper "joint frame design and resource allocation for ultra reliable and low latency vehicular networks"):
  with members:
    - "optimized power control for massive mimo with underlaid d2d communications"
    - "ultra reliable and low latency communications for connected vehicles challenges and solutions"
    - "a two stage allocation scheme for delay sensitive services in dense vehicular networks"
    - "high reliability and low latency for vehicular networks challenges and solutions"
    - "generalized cross layer designs for generic half duplex multicarrier wireless networks with frequency reuse"
    - "reliable and efficient autonomous driving the need for heterogeneous vehicular networks"
    - "energy and spectral efficiency of very large multiuser mimo systems"
    - "information spectrum approach to second order coding rate in channel coding"

Connected through hyperedge HE-2 (induced by source paper "massive mimo for internet of things iot connectivity"):
  with members:
    - "massive mimo unsourced random access"
    - "ultrareliable and low latency communication techniques for tactile internet services"
    - "non stationarities in extra large scale massive mimo"
    - "ubiquitous cell free massive mimo communications"
    - "sparcs for unsourced random access"
    - "management of network slicing in 5g radio access networks functional framework and information models"
    - "grant free massive mtc enabled massive mimo a compressive sensing approach"
    - "massive mimo for ultra reliable communications with constellations for dual coherent noncoherent detection"

Connected through hyperedge HE-3 (induced by source paper "on the spectral efficiency for massive mimo systems with imperfect spacial covariance information"):
  with members:
    - "covariance matrix estimation for massive mimo"
    - "covariance matrix estimation in massive mimo"
    - "massive mimo has unlimited capacity"
    - "massive mimo pilot decontamination and channel interpolation via wideband sparse channel estimation"
    - "massive mimo with imperfect channel covariance information"
    - "path loss shadow fading and line of sight probability models for 5g urban macro cellular scenarios"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"

Connected through hyperedge HE-4 (induced by source paper "learning based rate adaptation for uplink massive mimo networks with cooperative data assisted detection"):
  with members:
    - "on the uplink achievable rate for massive mimo with 1 bit adc and superimposed pilots"
    - "analyzing uplink sinr and rate in massive mimo systems using stochastic geometry"

Connected through hyperedge HE-5 (induced by source paper "on the uplink achievable rate for massive mimo with 1 bit adc and superimposed pilots"):
  with members:
    - "throughput analysis of massive mimo uplink with low resolution adcs"
    - "channel estimation and performance analysis of one bit massive mimo systems"
    - "blind estimation of sparse broadband massive mimo channels with ideal and one bit adcs"
    - "uplink performance of wideband massive mimo with one bit adcs"
    - "bayes optimal joint channel and data estimation for massive mimo with low precision adcs"
    - "mixed adc massive mimo"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "low power analog to digital conversion in millimeter wave systems impact of resolution and bandwidth on performance"

Connected through hyperedge HE-6 (induced by source paper "covariance matrix estimation for massive mimo"):
  with members:
    - "massive mimo has unlimited capacity"
    - "massive mimo pilot decontamination and channel interpolation via wideband sparse channel estimation"
    - "massive mimo with imperfect channel covariance information"
    - "downlink performance of superimposed pilots in massive mimo systems"
    - "pilot contamination is not a fundamental asymptotic limitation in massive mimo"
    - "superimposed pilots are superior for mitigating pilot contamination in massive mimo part ii performance analysis and hybrid system design"
    - "massive mimo for next generation wireless systems"
    - "blind pilot decontamination"

Connected through hyperedge HE-7 (induced by source paper "a simple capacity lower bound for communication with superimposed pilots"):
  with members:
    - "a rate splitting approach to fading channels with imperfect channel state information"
    - "nearest neighbour decoding and pilot aided channel estimation in stationary gaussian flat fading channels"
    - "what is the value of joint processing of pilots and data in block fading channels"
    - "the noncoherent rician fading channel part i structure of the capacity achieving input"

Connected through hyperedge HE-8 (induced by source paper "downlink performance of superimposed pilots in massive mimo systems"):
  with members:
    - "pilot contamination is not a fundamental asymptotic limitation in massive mimo"
    - "massive mimo systems with non ideal hardware energy efficiency estimation and capacity limits"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"
    - "blind pilot decontamination"
    - "massive mimo for maximal spectral efficiency how many users and pilots should be allocated"
    - "five disruptive technology directions for 5g"
    - "on an achievable rate of large rayleigh block fading mimo channels with no csi"

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)