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: "please lower small cell antenna heights in 5g"
  Abstract: In this paper, we present a new and significant theoretical discovery. If the absolute height difference between base station (BS) antenna and user equipment (UE) antenna is larger than zero, then the network capacity performance in terms of the area spectral efficiency (ASE) will continuously decrease as the BS density increases for ultra-dense (UD) small cell networks (SCNs). This performance behavior has a tremendous impact on the deployment of UD SCNs in the 5th- generation (5G) era. Network operators may invest large amounts of money in deploying more network infrastructure to only obtain an even worse network performance. Our study results reveal that it is a must to lower the SCN BS antenna height to the UE antenna height to fully achieve the capacity gains of UD SCNs in 5G. However, this requires a revolutionized approach of BS architecture and deployment, which is explored in this paper too.

Connected through hyperedge HE-1 (induced by source paper "survey on uav cellular communications practical aspects standardization advancements regulation and security challenges"):
  with members:
    - "understanding uav cellular communications from existing networks to massive mimo"
    - "supporting uav cellular communications through massive mimo"
    - "uav aided offloading for cellular hotspot"
    - "the essential guide to realizing 5g connected uavs with massive mimo"
    - "performance analysis for practical unmanned aerial vehicle networks with los nlos transmissions"
    - "promises and caveats of uplink iot ultra dense networks"
    - "the sky is not the limit lte for unmanned aerial vehicles"
    - "cellular enabled uav communication a connectivity constrained trajectory optimization perspective"

Connected through hyperedge HE-2 (induced by source paper "optimal base station antenna downtilt in downlink cellular networks"):
  with members:
    - "performance analysis of ultra dense networks with elevated base stations"
    - "ultra dense networks is there a limit to spatial spectrum reuse"
    - "performance impact of base station antenna heights in dense cellular networks"
    - "joint tilt angle adaptation and beamforming in multicell multiuser cellular networks"
    - "energy efficiency optimization of 5g radio frequency chain systems"
    - "performance impact of los and nlos transmissions in dense cellular networks"
    - "spatial spectrum and energy efficiency of random cellular networks"
    - "towards 1 gbps ue in cellular systems understanding ultra dense small cell deployments"

Connected through hyperedge HE-3 (induced by source paper "optimal coverage and rate in downlink cellular networks a sir meta distribution based approach"):
  with members:
    - "sir meta distribution of k tier downlink heterogeneous cellular networks with cell range expansion"
    - "the spatial outage capacity of wireless networks"
    - "downlink cellular network analysis with los nlos propagation and elevated base stations"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "the meta distribution of the sir for cellular networks with power control"
    - "propagation path loss models for 5g urban micro and macro cellular scenarios"
    - "performance impact of los and nlos transmissions in dense cellular networks"
    - "the meta distribution of the sir in poisson bipolar and cellular networks"

Connected through hyperedge HE-4 (induced by source paper "integrating uavs into existing wireless networks a stochastic geometry approach"):
  with members:
    - "a tutorial on uavs for wireless networks applications challenges and open problems"
    - "handover rate characterization in 3d ultra dense heterogeneous networks"
    - "a stochastic geometry model of backhaul and user coverage in urban uav networks"
    - "survey of important issues in uav communication networks"
    - "designing and implementing future aerial communication networks"
    - "handover management in 5g and beyond a topology aware skipping approach"
    - "mobility aware modeling and analysis of dense cellular networks with c plane u plane split architecture"
    - "wireless communications with unmanned aerial vehicles opportunities and challenges"

Connected through hyperedge HE-5 (induced by source paper "performance analysis for practical unmanned aerial vehicle networks with los nlos transmissions"):
  with members:
    - "ultra dense networks is there a limit to spatial spectrum reuse"
    - "dynamic base station repositioning to improve spectral efficiency of drone small cells"
    - "unmanned aerial vehicle with underlaid device to device communications performance and tradeoffs"
    - "performance impact of los and nlos transmissions in dense cellular networks"
    - "drone small cells in the clouds design deployment and performance analysis"

Connected through hyperedge HE-6 (induced by source paper "handover rate characterization in 3d ultra dense heterogeneous networks"):
  with members:
    - "downlink cellular network analysis with los nlos propagation and elevated base stations"
    - "5g ultra dense cellular networks"
    - "towards understanding the fundamentals of mobility in cellular networks"
    - "heterogeneous cellular networks with flexible cell association a comprehensive downlink sinr analysis"
    - "a tractable approach to coverage and rate in cellular networks"

Connected through hyperedge HE-7 (induced by source paper "downlink cellular network analysis with los nlos propagation and elevated base stations"):
  with members:
    - "sinr and throughput of dense cellular networks with stretched exponential path loss"
    - "modeling and analyzing millimeter wave cellular systems"
    - "performance analysis of ultra dense networks with elevated base stations"
    - "performance limits of network densification"
    - "power beacon assisted millimeter wave ad hoc networks"
    - "a 3 d spatial model for in building wireless networks with correlated shadowing"
    - "coverage and capacity scaling laws in downlink ultra dense cellular networks"
    - "study on the idle mode capability with los and nlos transmissions"

Connected through hyperedge HE-8 (induced by source paper "the major and minor factors in the performance analysis of ultra dense networks"):
  with members:
    - "study on the idle mode capability with los and nlos transmissions"
    - "microscopic analysis of the uplink interference in fdma small cell networks"
    - "nearest neighbour distance distribution in hard core point processes"
    - "throughput and coverage for a mixed full and half duplex small cell network"
    - "the intensity matching approach a tractable stochastic geometry approximation to system level analysis of cellular networks"
    - "what is the true value of dynamic tdd a mac layer perspective"
    - "performance impact of los and nlos transmissions in dense cellular networks"
    - "uplink performance analysis of dense cellular networks with los and nlos transmissions"

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)