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 "channel estimation for orthogonal time frequency space otfs massive mimo"):
  Abstract: Orthogonal time frequency space (OTFS) modulation outperforms orthogonal frequency division multiplexing (OFDM) in high-mobility scenarios. One challenge for OTFS massive MIMO is downlink channel estimation due to the large number of base station antennas. In this paper, we propose a 3D structured orthogonal matching pursuit algorithm based channel estimation technique to solve this problem. First, we show that the OTFS MIMO channel exhibits 3D structured sparsity: normal sparsity along the delay dimension, block sparsity along the Doppler dimension, and burst sparsity along the angle dimension. Based on the 3D structured channel sparsity, we then formulate the downlink channel estimation problem as a sparse signal recovery problem. Simulation results show that the proposed algorithm can achieve accurate channel state information with low pilot overhead.

Includes members:
  Member "mimo otfs in high doppler fading channels signal detection and channel estimation":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "otfs based receiver scheme with multi antennas in high mobility v2x systems")
  Member "orthogonal time frequency space modulation":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "multiple access in the delay doppler domain using otfs modulation")
  Member "otfs a new generation of modulation addressing the challenges of 5g":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "otfs interleaved ofdm with block cp")
  Member "embedded pilot aided channel estimation for otfs in delay doppler channels":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "otfs interleaved ofdm with block cp")
  Member "on otfs modulation for high doppler fading channels":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "otfs noma an efficient approach for exploiting heterogenous user mobility profiles")
  Member "interference cancellation and iterative detection for orthogonal time frequency space modulation":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "otfs based receiver scheme with multi antennas in high mobility v2x systems")
  Member "a simple two stage equalizer with simplified orthogonal time frequency space modulation over rapidly time varying channels":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "multiple access in the delay doppler domain using otfs modulation")
  Member "low complexity modem structure for ofdm based orthogonal time frequency space modulation":
    also connected through other hyperedges:
      - Hyperedge HE-8 (induced by source paper "multiple access in the delay doppler domain using otfs modulation")

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)