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: "filter bank multicarrier for massive mimo"
  Abstract: This paper introduces filter bank multicarrier (FBMC) as a potential candidate in the application of massive MIMO communication. It also points out the advantages of FBMC over OFDM (orthogonal frequency division multiplexing) in the application of massive MIMO. The absence of cyclic prefix in FBMC increases the bandwidth efficiency. In addition, FBMC allows carrier aggregation straightforwardly. Self-equalization, a property of FBMC in massive MIMO that is introduced in this paper, has the impact of reducing (i) complexity; (ii) sensitivity to carrier frequency offset (CFO); (iii) peak-to-average power ratio (PAPR); (iv) system latency; and (v) increasing bandwidth efficiency. The numerical results that corroborate these claims are presented.

Connected through hyperedge HE-1 (induced by source paper "filter bank multicarrier in massive mimo analysis and channel equalization"):
  with members:
    - "prototype filter design for fbmc in massive mimo channels"
    - "cell free massive mimo versus small cells"
    - "ofdm without cp in massive mimo"
    - "frequency spreading equalization in multicarrier massive mimo"
    - "impact of timing and frequency offsets on multicarrier waveform candidates for 5g"
    - "pilot decontamination in cmt based massive mimo networks"
    - "five disruptive technology directions for 5g"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-2 (induced by source paper "fundamental green tradeoffs progresses challenges and impacts on 5g networks"):
  with members:
    - "spectrum power trading for energy efficient small cell"
    - "power efficient resource allocation for full duplex radio distributed antenna networks"
    - "energy recycling full duplex radios for next generation networks"
    - "energy efficient resource allocation for wireless powered communication networks"
    - "multi objective optimization for robust power efficient and secure full duplex wireless communication systems"
    - "hybrid millimeter wave systems a novel paradigm for hetnets"
    - "coexistence of wi fi and heterogeneous small cell networks sharing unlicensed spectrum"
    - "on the spectral efficiency of full duplex small cell wireless systems"

Connected through hyperedge HE-3 (induced by source paper "ofdm without cp in massive mimo"):
  with members:
    - "time reversal with post equalization for ofdm without cp in massive mimo"
    - "massive mimo in real propagation environments do all antennas contribute equally"
    - "uplink performance of time reversal mrc in massive mimo systems subject to phase noise"
    - "massive mimo with non ideal arbitrary arrays hardware scaling laws and circuit aware design"
    - "equalized time reversal beamforming for indoor wireless communications"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-4 (induced by source paper "prototype filter design for fbmc in massive mimo channels"):
  with members:
    - "massive mimo and waveform design for 5th generation wireless communication systems"
    - "frequency spreading equalization in multicarrier massive mimo"
    - "impact of timing and frequency offsets on multicarrier waveform candidates for 5g"
    - "pilot decontamination in cmt based massive mimo networks"
    - "five disruptive technology directions for 5g"
    - "energy and spectral efficiency of very large multiuser mimo systems"

Connected through hyperedge HE-5 (induced by source paper "time reversal with post equalization for ofdm without cp in massive mimo"):
  with members:
    - "massive mimo in real propagation environments do all antennas contribute equally"
    - "uplink performance of time reversal mrc in massive mimo systems subject to phase noise"
    - "massive mimo with non ideal arbitrary arrays hardware scaling laws and circuit aware design"
    - "massive mimo for next generation wireless systems"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-6 (induced by source paper "low complexity modem design for gfdm"):
  with members:
    - "interference localization for uplink ofdma systems in presence of cfos"

Connected through hyperedge HE-7 (induced by source paper "massive mimo with non ideal arbitrary arrays hardware scaling laws and circuit aware design"):
  with members:
    - "capacity of simo and miso phase noise channels with common separate oscillators"
    - "uplink performance of time reversal mrc in massive mimo systems subject to phase noise"
    - "massive mimo performance evaluation based on measured propagation data"
    - "optimal multiuser transmit beamforming a difficult problem with a simple solution structure"
    - "on the impact of oscillator phase noise on the uplink performance in a massive mimo ofdm system"
    - "massive mimo systems with non ideal hardware energy efficiency estimation and capacity limits"
    - "massive mimo for next generation wireless systems"
    - "capacity bounds for mimo microwave backhaul links affected by phase noise"

Connected through hyperedge HE-8 (induced by source paper "massive mimo and waveform design for 5th generation wireless communication systems"):
  with members:
    - "achievable rates of fdd massive mimo systems with spatial channel correlation"
    - "pilot decontamination in cmt based massive mimo networks"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"
    - "blind pilot decontamination"
    - "modulation formats and waveforms for the physical layer of 5g wireless networks who will be the heir of ofdm"
    - "generalized design of low complexity block diagonalization type precoding algorithms for multiuser mimo systems"
    - "scalable synchronization and reciprocity calibration for distributed multiuser mimo"

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)