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: "achieving large multiplexing gain in distributed antenna systems via cooperation with pcell technology"
  Abstract: In this paper we present pCellTM technology, the first commercial-grade wireless system that employs cooperation between distributed transceiver stations to create concurrent data links to multiple users in the same spectrum. First we analyze the per-user signal-to-interference-plus-noise ratio (SINR) employing a geometrical spatial channel model to define volumes in space of coherent signal around user antennas (or personal cells, i.e., pCells). Then we describe the system architecture consisting of a general-purpose-processor (GPP) based software-defined radio (SDR) wireless platform implementing a real-time LTE protocol stack to communicate with off-the-shelf LTE devices. Finally we present experimental results demonstrating up to 16 concurrent spatial channels for an aggregate average spectral efficiency of 59.3 bps/Hz in the downlink and 27.5 bps/Hz in the uplink, providing data rates of 200 Mbps downlink and 25 Mbps uplink in 5 MHz of TDD spectrum.1

Connected through hyperedge HE-1 (induced by source paper "ubiquitous cell free massive mimo communications"):
  with members:
    - "downlink training in cell free massive mimo a blessing in disguise"
    - "scalability aspects of cell free massive mimo"
    - "making cell free massive mimo competitive with mmse processing and centralized implementation"
    - "fog massive mimo a user centric seamless hot spot architecture"
    - "enhancing favorable propagation in cell free massive mimo through spatial user grouping"
    - "on the total energy efficiency of cell free massive mimo"
    - "channel hardening and favorable propagation in cell free massive mimo with stochastic geometry"
    - "cell free massive mimo versus small cells"

Connected through hyperedge HE-2 (induced by source paper "analysis of massive mimo and base station cooperation in an indoor scenario"):
  with members:
    - "massive mimo ten myths and one critical question"
    - "large scale mimo versus network mimo for multicell interference mitigation"
    - "massive mimo for next generation wireless systems"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "a quantitative measure of fairness and discrimination for resource allocation in shared computer systems"

Connected through hyperedge HE-3 (induced by source paper "distributed fd mimo cellular evolution for 5g and beyond"):
  with members:
    - "cell free massive mimo versus small cells"

Connected through hyperedge HE-4 (induced by source paper "on the ergodic rate lower bounds with applications to massive mimo"):
  with members:
    - "channel hardening and favorable propagation in cell free massive mimo with stochastic geometry"
    - "on the role of transmit correlation diversity in multiuser mimo systems"
    - "low rank covariance assisted downlink training and channel estimation for fdd massive mimo systems"
    - "no downlink pilots are needed in tdd massive mimo"
    - "cell free massive mimo uniformly great service for everyone"
    - "massive mimo for next generation wireless systems"
    - "massive mu mimo downlink tdd systems with linear precoding and downlink pilots"
    - "joint spatial division and multiplexing for mm wave channels"

Connected through hyperedge HE-5 (induced by source paper "wiflix adaptive video streaming in massive mu mimo wireless networks"):
  with members:
    - "performance analysis of massive mimo for cell boundary users"
    - "a control theoretic approach to adaptive video streaming in dense wireless networks"
    - "adaptive video streaming for wireless networks with multiple users and helpers"
    - "optimal user cell association for massive mimo wireless networks"
    - "what will 5g be"
    - "nova qoe driven optimization of dash based video delivery in networks"
    - "loss visibility optimized real time video transmission over mimo systems"
    - "joint spatial division and multiplexing for mm wave channels"

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)