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: "on the optimal number of cooperative base stations in network mimo systems"
  Abstract: We consider a multi-cell, frequency-selective fading, uplink channel (network MIMO) where K user terminals (UTs) communicate simultaneously with B cooperative base stations (BSs). Although the potential benefit of multi-cell cooperation grows with B, the overhead related to the acquisition of channel state information (CSI) will rapidly dominate the uplink resource. Thus, there exists a non-trivial tradeoff between the performance gains of network MIMO and the related overhead in channel estimation for a finite coherence time. Using a close approximation of the net ergodic achievable rate based on recent results from random matrix theory, we study this tradeoff by taking some realistic aspects into account such as unreliable backhaul links and different path losses between the UTs and BSs. We determine the optimal training length, the optimal number of cooperative BSs and the optimal number of sub-carriers to be used for an extended version of the circular Wyner model where each UT can communicate with B BSs. Our results provide some insight into practical limitations as well as realistic dimensions of network MIMO systems.

Connected through hyperedge HE-1 (induced by source paper "network mimo with linear zero forcing beamforming large system analysis impact of channel estimation and reduced complexity scheduling"):
  with members:
    - "multi cell mimo downlink with cell cooperation and fair scheduling a large system limit analysis"
    - "multiuser miso transmitter optimization for intercell interference mitigation"
    - "base station cooperation on the downlink large system analysis"
    - "channel state feedback over the mimo mac"
    - "cooperative multi cell block diagonalization with per base station power constraints"
    - "mimo downlink scheduling with non perfect channel state knowledge"
    - "training and feedback optimization for multiuser mimo downlink"
    - "mimo broadcast channel optimization under general linear constraints"

Connected through hyperedge HE-2 (induced by source paper "achieving massive mimo spectral efficiency with a not so large number of antennas"):
  with members:
    - "network mimo with linear zero forcing beamforming large system analysis impact of channel estimation and reduced complexity scheduling"
    - "multi cell mimo downlink with cell cooperation and fair scheduling a large system limit analysis"
    - "massive mimo how many antennas do we need"
    - "multiuser miso transmitter optimization for intercell interference mitigation"
    - "base station cooperation on the downlink large system analysis"
    - "asymptotic performance of linear receivers in mimo fading channels"
    - "mimo downlink scheduling with non perfect channel state knowledge"
    - "pilot contamination and precoding in multi cell tdd systems"

Connected through hyperedge HE-3 (induced by source paper "base station cooperation on the downlink large system analysis"):
  with members:
    - "large system analysis of linear precoding in correlated miso broadcast channels under limited feedback"
    - "a deterministic equivalent for the analysis of correlated mimo multiple access channels"
    - "optimal channel training in uplink network mimo systems"
    - "multi cell mimo downlink with fairness criteria the large system limit"
    - "on the optimal number of cooperative base stations in network mimo"
    - "a central limit theorem for the sinr at the lmmse estimator output for large dimensional signals"

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)