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: "optimal structure of robust linear transceiver for amplify and forward multi hop mimo relaying systems"
  Abstract: AbstractIn this paper, optimal linear transceiver designs for multi-hop amplify-and-forward (AF) Multiple-input Multiple-out (MIMO) relaying systems with Gaussian distributed channel estimation errors areinvestigated. Some commonly used transceiver design criteria such as weighted mean-square-error(MSE)minimization, mutual information maximization, worst MSE/MAX-MSE minimization and weightedsum-rate maximization, are taken into a single matrix-variate optimization problem. Exploiting ma-jorization theory and properties of matrix-variate functions, the optimal structures of robust transceiversare derived. Based on the optimal structures, the original transceiver design problems are reduced tomuch simpler problems with only scalar variables whose solutions are readily obtained by iterative water-ﬁlling algorithms. A number of existing transceiver design algorithms are found to be special cases ofthe proposed solution. The performance advantages of the proposed robust designs are demonstrated bythe simulation results.Index TermsAmplify-and-forward(AF), MIMO relaying, matrix-variateoptimization problems, robust transceiverdesign

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)