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: "massive mimo meets hetnet interference coordination through spatial blanking"
  Abstract: In this paper, we study the downlink performance of a heterogeneous cellular network (HetNet) where both macro and small cells share the same spectrum and hence interfere with each other. We assume that the users are concentrated at certain areas in the cell, i.e., they form hotspots. While some of the hotspots are assumed to have a small cell in their vicinity, the others are directly served by the macrocell. Due to a relatively small area of each hotspot, the users lying in a particular hotspot appear to be almost co-located to the macrocells, which are typically deployed at some elevation. Assuming large number of antennas at the macrocell, we exploit this directionality in the channel vectors to obtain spatial blanking, i.e., concentrating transmission energy only in certain directions while creating transmission opportunities for the small cells lying in the other directions. In addition to this inherent interference suppression, we also develop three low-complexity interference coordination strategies: (i) turn off small cells based on the amount of cross-tier interference they receive or cause to the scheduled macrocell hotspots, (ii) schedule hotspots such that treating interference as noise is approximately optimal for the resulting Gaussian interference channel, and (iii) offload some of the macrocell hotspots to nearby small cells in order to improve throughput fairness across all hotspots. For all these schemes, we study the relative merits and demerits of uniform deployment of small cells vs. deploying more small cells towards the cell center or the cell edge.

Connected through hyperedge HE-1 (induced by source paper "non coherent detection and bit error rate for an ambient backscatter link in time selective fading"):
  with members:
    - "ambient backscatter systems exact average bit error rate under fading channels"
    - "modulation in the air backscatter communication over ambient ofdm carrier"
    - "semi coherent detection and performance analysis for ambient backscatter system"
    - "wide area wireless communication challenges for the internet of things"
    - "wireless backhaul networks capacity bound scalability analysis and design guidelines"
    - "joint spatial division and multiplexing for mm wave channels"

Connected through hyperedge HE-2 (induced by source paper "non orthogonal multiple access for 5g and beyond"):
  with members:
    - "downlink non orthogonal multiple access with limited feedback"
    - "optimal user scheduling and power allocation for millimeter wave noma systems"
    - "coordinated multi point comp transmission in downlink multi cell noma systems models and spectral efficiency performance"
    - "low complexity receiver for multi level polar coded modulation in non orthogonal multiple access"
    - "massive non orthogonal multiple access for cellular iot potentials and limitations"
    - "power domain non orthogonal multiple access noma in 5g systems potentials and challenges"
    - "modulation and multiple access for 5g networks"
    - "robust beamforming techniques for non orthogonal multiple access systems with bounded channel uncertainties"

Connected through hyperedge HE-3 (induced by source paper "a data aided channel estimation scheme for decoupled systems in heterogeneous networks"):
  with members:
    - "performance impact of los and nlos transmissions in dense cellular networks"
    - "why to decouple the uplink and downlink in cellular networks and how to do it"
    - "analysis of the decoupled access for downlink and uplink in wireless heterogeneous networks"
    - "joint rate and sinr coverage analysis for decoupled uplink downlink biased cell associations in hetnets"
    - "what will 5g be"
    - "downlink and uplink decoupling a disruptive architectural design for 5g networks"
    - "load backhaul aware decoupled downlink uplink access in 5g systems"
    - "massive mimo and small cells improving energy efficiency by optimal soft cell coordination"

Connected through hyperedge HE-4 (induced by source paper "energy efficient massive mimo through distributed precoder design"):
  with members:
    - "joint user scheduling and beam selection optimization for beam based massive mimo downlinks"
    - "harvest the potential of massive mimo with multi layer techniques"
    - "green 5g heterogeneous networks through dynamic small cell operation"
    - "the concrete distribution a continuous relaxation of discrete random variables"
    - "massive mimo ten myths and one critical question"
    - "large scale convex optimization for dense wireless cooperative networks"
    - "distributed constrained optimization by consensus based primal dual perturbation method"
    - "distributed robust multicell coordinated beamforming with imperfect csi an admm approach"

Connected through hyperedge HE-5 (induced by source paper "non orthogonal multiple access in large scale heterogeneous networks"):
  with members:
    - "massive non orthogonal multiple access for cellular iot potentials and limitations"
    - "modulation and multiple access for 5g networks"
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "enhancing the physical layer security of non orthogonal multiple access in large scale networks"
    - "cooperative non orthogonal multiple access with simultaneous wireless information and power transfer"
    - "the application of mimo to non orthogonal multiple access"
    - "user association and interference management in massive mimo hetnets"
    - "fairness for non orthogonal multiple access in 5g systems"

Connected through hyperedge HE-6 (induced by source paper "multi cell massive mimo beamforming in assuring qos for large numbers of users"):
  with members:
    - "performance analysis of massive mimo for cell boundary users"
    - "aspects of favorable propagation in massive mimo"
    - "massive mimo for next generation wireless systems"
    - "what will 5g be"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "large system analysis of linear precoding in correlated miso broadcast channels under limited feedback"
    - "energy and spectral efficiency of very large multiuser mimo systems"

Connected through hyperedge HE-7 (induced by source paper "on the role of transmit correlation diversity in multiuser mimo systems"):
  with members:
    - "a codebook based limited feedback system for large scale mimo"
    - "hierarchical interference mitigation for massive mimo cellular networks"
    - "joint spatial division and multiplexing for mm wave channels"
    - "a coordinated approach to channel estimation in large scale multiple antenna systems"
    - "network mimo with linear zero forcing beamforming large system analysis impact of channel estimation and reduced complexity scheduling"
    - "multiuser mimo achievable rates with downlink training and channel state feedback"

Connected through hyperedge HE-8 (induced by source paper "energy efficient power control for the two tier networks with small cells and massive mimo"):
  with members:
    - "interference management in 5g reverse tdd hetnets with wireless backhaul a large system analysis"
    - "what will 5g be"

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)