human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "ofdm without cp in massive mimo"):
  Abstract: We study the possibility of eliminating the redundant cyclic prefix (CP) of orthogonal frequency division multiplexing (OFDM) in massive multiple-input multiple-output (MIMO) systems. The absence of CP increases the bandwidth efficiency in expense of intersymbol interference (ISI) and intercarrier interference (ICI). It is known that in massive MIMO, different types of interferences vanish as the number of base station (BS) antennas tends to infinity. To investigate if the channel distortions in the absence of CP fade away, we first study the performance of the standard frequency-domain maximum ratio combining (MRC) receiver. Our analysis reveals that in this receiver there always remains some residual interference leading to saturation of signal-to-interference-plus-noise ratio (SINR). In order to resolve this saturation problem, we propose a receiver structure based on time-reversal equalization combined with a zero-forcing multiuser detector. A detailed mathematical analysis of this receiver, including a lower bound for its asymptotic achievable information rate, is presented. We evaluate our theoretical results through conducting numerical analysis where we compare the tightness of our closed-form expressions against the simulation results. Finally, our simulation results reveal that, in massive MIMO systems, the absence of CP in OFDM does not incur any noticeable performance loss.

Includes members:
  Member "time reversal with post equalization for ofdm without cp in massive mimo":
    also connected through other hyperedges:
      (none)
  Member "massive mimo in real propagation environments do all antennas contribute equally":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "localization efficiency in massive mimo systems")
  Member "uplink performance of time reversal mrc in massive mimo systems subject to phase noise":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "achieving phase coherency and gain stability in active antenna arrays for sub 6 ghz fdd and tdd fd mimo challenges and solutions")
  Member "massive mimo with non ideal arbitrary arrays hardware scaling laws and circuit aware design":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "joint power control and lsfd for wireless powered cell free massive mimo")
  Member "equalized time reversal beamforming for indoor wireless communications":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "interference nulling time reversal beamforming for mm wave massive mimo in multi user frequency selective indoor channels")
  Member "filter bank multicarrier for massive mimo":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "filter bank multicarrier in massive mimo analysis and channel equalization")
  Member "massive mimo for next generation wireless systems":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "joint power control and lsfd for wireless powered cell free massive mimo")
  Member "what will 5g be":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "5g network slicing using sdn and nfv a survey of taxonomy architectures and future challenges")

Question: Please tell me which class the source paper 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)