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: "exploiting multiple antenna techniques for non orthogonal multiple access"
  Abstract: This paper aims to provide a comprehensive solution for the design, analysis, and optimization of a multiple-antenna non-orthogonal multiple access (NOMA) system for multiuser downlink communication with both time duplex division (TDD) and frequency duplex division (FDD) modes. First, we design a new framework for multiple-antenna NOMA, including user clustering, channel state information (CSI) acquisition, superposition coding, transmit beamforming, and successive interference cancellation (SIC). Then, we analyze the performance of the considered system, and derive exact closed-form expressions for average transmission rates in terms of transmit power, CSI accuracy, transmission mode, and channel conditions. For further enhancing the system performance, we optimize three key parameters, i.e., transmit power, feedback bits, and transmission mode. Especially, we propose a low-complexity joint optimization scheme, so as to fully exploit the potential of multiple-antenna techniques in NOMA. Moreover, through asymptotic analysis, we reveal the impact of system parameters on average transmission rates, and hence present some guidelines on the design of multiple-antenna NOMA. Finally, simulation results validate our theoretical analysis, and show that a substantial performance gain can be obtained over traditional orthogonal multiple access (OMA) technology under practical conditions.

Connected through hyperedge HE-1 (induced by source paper "what role can noma play in massive mimo"):
  with members:
    - "performance analysis of noma in training based multiuser mimo systems"
    - "joint power allocation and beamforming for non orthogonal multiple access noma in 5g millimeter wave communications"
    - "a survey on non orthogonal multiple access for 5g networks research challenges and future trends"
    - "on the ergodic rate lower bounds with applications to massive mimo"
    - "design of massive mimo noma with limited feedback"
    - "no downlink pilots are needed in tdd massive mimo"
    - "aspects of favorable propagation in massive mimo"
    - "massive mimo for next generation wireless systems"

Connected through hyperedge HE-2 (induced by source paper "reconsidering design of multi antenna noma systems with limited feedback"):
  with members:
    - "design of massive mimo noma with limited feedback"
    - "energy efficient transmission design in non orthogonal multiple access"
    - "fairness for non orthogonal multiple access in 5g systems"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"
    - "mimo broadcast channels with finite rate feedback"

Connected through hyperedge HE-3 (induced by source paper "hybrid beamforming noma for mmwave communications"):
  with members:
    - "a new reconfigurable antenna mimo architecture for mmwave communication"
    - "multi beam noma for hybrid mmwave systems"
    - "reconfigurable antenna multiple access for 5g mmwave systems"
    - "non orthogonal multiple access based on hybrid beamforming for mmwave systems"
    - "non orthogonal multiple access common myths and critical questions"
    - "modeling and analyzing millimeter wave cellular systems"
    - "energy efficient power allocation in millimeter wave massive mimo with non orthogonal multiple access"
    - "joint power allocation and beamforming for non orthogonal multiple access noma in 5g millimeter wave communications"

Connected through hyperedge HE-4 (induced by source paper "impact of beam misalignment on hybrid beamforming noma for mmwave communications"):
  with members:
    - "a new reconfigurable antenna mimo architecture for mmwave communication"
    - "reconfigurable antenna multiple access for 5g mmwave systems"
    - "a multi beam noma framework for hybrid mmwave systems"
    - "non orthogonal multiple access based on hybrid beamforming for mmwave systems"
    - "modeling and analyzing millimeter wave cellular systems"
    - "energy efficient power allocation in millimeter wave massive mimo with non orthogonal multiple access"
    - "joint power allocation and beamforming for non orthogonal multiple access noma in 5g millimeter wave communications"
    - "noma meets finite resolution analog beamforming in massive mimo and millimeter wave networks"

Connected through hyperedge HE-5 (induced by source paper "beamforming techniques for non orthogonal multiple access in 5g cellular networks"):
  with members:
    - "secure communications with cooperative jamming optimal power allocation and secrecy outage analysis"
    - "physical layer security jamming theoretical limits and practical designs in wireless networks"
    - "robust beamforming techniques for non orthogonal multiple access systems with bounded channel uncertainties"
    - "limited feedback scheme for device to device communications in 5g cellular networks with reliability and cellular secrecy outage constraints"
    - "design of massive mimo noma with limited feedback"
    - "a minorization maximization method for optimizing sum rate in the downlink of non orthogonal multiple access systems"
    - "the application of mimo to non orthogonal multiple access"
    - "fairness for non orthogonal multiple access in 5g systems"

Connected through hyperedge HE-6 (induced by source paper "exploiting inter user interference for secure massive non orthogonal multiple access"):
  with members:
    - "analysis and design of secure massive mimo systems in the presence of hardware impairments"
    - "design of massive mimo noma with limited feedback"
    - "secrecy sum rate maximization in non orthogonal multiple access"
    - "on the spectral efficiency and security enhancements of noma assisted multicast unicast streaming"
    - "on the design of secure non orthogonal multiple access systems"
    - "a minorization maximization method for optimizing sum rate in the downlink of non orthogonal multiple access systems"
    - "enhancing the physical layer security of non orthogonal multiple access in large scale networks"
    - "secure massive mimo transmission with an active eavesdropper"

Connected through hyperedge HE-7 (induced by source paper "non orthogonal multiple access based on hybrid beamforming for mmwave systems"):
  with members:
    - "a new reconfigurable antenna mimo architecture for mmwave communication"
    - "reconfigurable antenna multiple access for 5g mmwave systems"
    - "energy efficient power allocation in millimeter wave massive mimo with non orthogonal multiple access"
    - "noma meets finite resolution analog beamforming in massive mimo and millimeter wave networks"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"
    - "spatially sparse precoding in millimeter wave mimo systems"

Connected through hyperedge HE-8 (induced by source paper "a survey on non orthogonal multiple access for 5g networks research challenges and future trends"):
  with members:
    - "achievable rate region of non orthogonal multiple access systems with wireless powered decoder"
    - "a new view of multi user hybrid massive mimo non orthogonal angle division multiple access"
    - "on non orthogonal multiple access with finite alphabet inputs in z channels"
    - "spectrum and energy efficient beamspace mimo noma for millimeter wave communications using lens antenna array"
    - "practical power balanced non orthogonal multiple access"
    - "noma based random access with multichannel aloha"
    - "optimal power allocation scheme for non orthogonal multiple access with alpha fairness"
    - "on optimal power allocation for downlink non orthogonal multiple access systems"

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)