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: "information theoretic performance of tr mrc receiver in frequency selective massive mu mimo systems impaired by cfo"
  Abstract: In this paper we study the impact of carrier frequency offset (CFO) impairment on massive multi-user (MU) multiple-input multiple-output (MIMO) system in frequency-selective fading channel. Our study reveals that with CFO estimation and compensation at the base station (BS), a time-reversed maximum ratio combining (TR-MRC) receiver can achieve an $\mathcal{O}(\sqrt{M})$ array gain, where $M$ is the number of BS antennas. Further study of the information rate expression reveals that the increase in the required per-user transmit power (to achieve a desired per-user information rate) with increasing number of channel taps ($L$) is insignificant when $L$ is sufficiently small (i.e. $L\ll$ CFO estimation pilot sequence length divided by the number of user terminals).

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)