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: "impact of user mobility on optimal linear receivers in cellular networks"
  Abstract: We consider the uplink of non-cooperative multi-cellular systems deploying multiple antenna elements at the base stations (BS), covering both the cases of conventional and very large number of antennas. Given the inevitable pilot contamination and an arbitrary path-loss for each link, we address the impact of time variation of the channel due to the relative movement between users and BS antennas, which limits system's performance even if the number antennas is increased, as shown. In particular, we propose an optimal linear receiver (OLR) maximizing the received signal-to-interference-plus-noise (SINR). Closed-form lower and upper bounds are derived as well as the deterministic equivalent of the OLR is obtained. Numerical results reveal the outperformance of the proposed OLR against known linear receivers, mostly in environments with high interference and certain user mobility, as well as that massive MIMO is preferable even in time-varying channel conditions.

Connected through hyperedge HE-1 (induced by source paper "modeling and performance of uplink cache enabled massive mimo heterogeneous networks"):
  with members:
    - "toward a realistic assessment of multiple antenna hcns residual additive transceiver hardware impairments and channel aging"
    - "impact of general channel aging conditions on the downlink performance of massive mimo"
    - "downlink mimo hcns with residual transceiver hardware impairments"
    - "cluster content caching an energy efficient approach to improve quality of service in cloud radio access networks"
    - "deploying dense networks for maximal energy efficiency small cells meet massive mimo"
    - "an uplink interference analysis for massive mimo systems with mrc and zf receivers"
    - "massive mimo with non ideal arbitrary arrays hardware scaling laws and circuit aware design"
    - "analyzing uplink sinr and rate in massive mimo systems using stochastic geometry"

Connected through hyperedge HE-2 (induced by source paper "impact of general channel aging conditions on the downlink performance of massive mimo"):
  with members:
    - "massive mimo ten myths and one critical question"
    - "massive mimo 10 myths and one grand question"
    - "sum rate and power scaling of massive mimo systems with channel aging"
    - "downlink performance of massive mimo under general channel aging conditions"
    - "uplink performance of time reversal mrc in massive mimo systems subject to phase noise"
    - "uplink performance of conventional and massive mimo cellular systems with delayed csit"
    - "massive mimo with non ideal arbitrary arrays hardware scaling laws and circuit aware design"
    - "on the impact of oscillator phase noise on the uplink performance in a massive mimo ofdm system"

Connected through hyperedge HE-3 (induced by source paper "downlink performance of massive mimo under general channel aging conditions"):
  with members:
    - "uplink performance of time reversal mrc in massive mimo systems subject to phase noise"
    - "massive mimo with non ideal arbitrary arrays hardware scaling laws and circuit aware design"
    - "massive mimo for next generation wireless systems"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "effects of channel aging in massive mimo systems"
    - "energy and spectral efficiency of very large multiuser mimo systems"

Connected through hyperedge HE-4 (induced by source paper "impact of transceiver impairments on the capacity of dual hop relay massive mimo systems"):
  with members:
    - "on the mimo capacity with residual transceiver hardware impairments"
    - "capacity limits and multiplexing gains of mimo channels with transceiver impairments"
    - "a new look at dual hop relaying performance limits with hardware impairments"
    - "mimo transmission with residual transmit rf impairments"
    - "ergodic capacity analysis of amplify and forward mimo dual hop systems"

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)