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: "throughput and energy efficiency analysis of small cell networks with multi antenna base stations"
  Abstract: Small cell networks have recently been proposed as an important evolution path for the next-generation cellular networks. However, with more and more irregularly deployed base stations (BSs), it is becoming increasingly difficult to quantify the achievable network throughput or energy efficiency. In this paper, we develop an analytical framework for downlink performance evaluation of small cell networks, based on a random spatial network model, where BSs and users are modeled as two independent spatial Poisson point processes. A new simple expression of the outage probability is derived, which is analytically tractable and is especially useful with multi-antenna transmissions. This new result is then applied to evaluate the network throughput and energy efficiency. It is analytically shown that deploying more BSs or more BS antennas can always increase the network throughput, but the performance gain critically depends on the BS-user density ratio and the number of BS antennas. On the other hand, increasing the BS density or the number of transmit antennas will first increase and then decrease the energy efficiency if different components of BS power consumption satisfy certain conditions, and the optimal BS density and the optimal number of BS antennas can be found. Otherwise, the energy efficiency will always decrease. Simulation results shall demonstrate that our conclusions based on the random network model are general and also hold in a regular grid-based model.

Connected through hyperedge HE-1 (induced by source paper "enhancing physical layer security of random caching in large scale multi antenna heterogeneous wireless networks"):
  with members:
    - "secure and energy efficient transmissions in cache enabled heterogeneous cellular networks performance analysis and optimization"
    - "enhancing performance of random caching in large scale wireless networks with multiple receive antennas"
    - "physical layer security in cache enabled cooperative small cell networks against randomly distributed eavesdroppers"
    - "a unified framework for the tractable analysis of multi antenna wireless networks"
    - "enhancing performance of random caching in large scale heterogeneous wireless networks with random discontinuous transmission"
    - "delivery secrecy tradeoff for cache enabled stochastic networks content placement optimization"
    - "random caching based cooperative transmission in heterogeneous wireless networks"
    - "caching at the wireless edge design aspects challenges and future directions"

Connected through hyperedge HE-2 (induced by source paper "a mobility aware vehicular caching scheme in content centric networks model and optimization"):
  with members:
    - "building transmission backbone for highway vehicular networks framework and analysis"
    - "throughput of infrastructure based cooperative vehicular networks"
    - "high reliability and low latency for vehicular networks challenges and solutions"
    - "order optimal rate of caching and coded multicasting with random demands"
    - "femtocaching and device to device collaboration a new architecture for wireless video distribution"

Connected through hyperedge HE-3 (induced by source paper "a unified framework for the tractable analysis of multi antenna wireless networks"):
  with members:
    - "3gpp inspired hetnet model using poisson cluster process sum product functionals and downlink coverage"
    - "coverage analysis for millimeter wave networks the impact of directional antenna arrays"
    - "a tractable framework for performance analysis of dense multi antenna networks"
    - "ergodic spectral efficiency in mimo cellular networks"
    - "asymptotics and approximation of the sir distribution in general cellular networks"
    - "success probability and area spectral efficiency in multiuser mimo hetnets"
    - "downlink cellular network analysis with multi slope path loss models"
    - "user centric intercell interference nulling for downlink small cell networks"

Connected through hyperedge HE-4 (induced by source paper "5g massive mimo architectures self backhauled small cells versus direct access"):
  with members:
    - "performance analysis for practical unmanned aerial vehicle networks with los nlos transmissions"
    - "performance of massive mimo self backhauling for ultra dense small cell deployments"
    - "performance of dynamic and static tdd in self backhauled millimeter wave cellular networks"
    - "uplink sounding reference signal coordination to combat pilot contamination in 5g massive mimo"
    - "joint backhaul access analysis of full duplex self backhauling heterogeneous networks"
    - "analysis of massive mimo enabled downlink wireless backhauling for full duplex small cells"
    - "the new frontier in ran heterogeneity multi tier drone cells"
    - "performance impact of los and nlos transmissions in dense cellular networks"

Connected through hyperedge HE-5 (induced by source paper "system level modeling and optimization of the energy efficiency in cellular networks a stochastic geometry framework"):
  with members:
    - "effect of densification on cellular network performance with bounded pathloss model"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "enhanced cellular coverage and throughput using rateless codes"
    - "area spectral efficiency analysis and energy consumption minimization in multiantenna poisson distributed networks"
    - "stochastic geometric analysis of energy efficient dense cellular networks"
    - "the intensity matching approach a tractable stochastic geometry approximation to system level analysis of cellular networks"
    - "a survey of energy efficient techniques for 5g networks and challenges ahead"
    - "spatial spectrum and energy efficiency of random cellular networks"

Connected through hyperedge HE-6 (induced by source paper "effective capacity analysis in ultra dense wireless networks with random interference"):
  with members:
    - "effective capacity of licensed assisted access in unlicensed spectrum for 5g from theory to application"
    - "sinr and throughput scaling in ultradense urban cellular networks"
    - "downlink capacity and base station density in cellular networks"

Connected through hyperedge HE-7 (induced by source paper "load based on off scheduling for energy efficient delay tolerant 5g networks"):
  with members:
    - "ultra dense small cell networks turning density into energy efficiency"
    - "analysis of cell load coupling for lte network planning and optimization"

Connected through hyperedge HE-8 (induced by source paper "the stochastic geometry analyses of cellular networks with alpha stable self similarity"):
  with members:
    - "system level modeling and optimization of the energy efficiency in cellular networks a stochastic geometry framework"
    - "delivery secrecy tradeoff for cache enabled stochastic networks content placement optimization"
    - "self interference in full duplex multi user mimo channels"
    - "secrecy outage analysis for downlink transmissions in the presence of randomly located eavesdroppers"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "analytical modeling of interference aware power control for the uplink of heterogeneous cellular networks"
    - "analysis of massive mimo enabled downlink wireless backhauling for full duplex small cells"
    - "the learning and prediction of application level traffic data in cellular networks"

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)