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: "performance characterization of a real time massive mimo system with los mobile channels"
  Abstract: The first measured results for massive multiple input, multiple-output (MIMO) performance in a line-of-sight (LOS) scenario with moderate mobility are presented, with 8 users served in real-time using a 100 antenna base Station (BS) at 3.7 GHz. When such a large number of channels dynamically change, the inherent propagation and processing delay has a critical relationship with the rate of change, as the use of outdated channel information can result in severe detection and precoding inaccuracies. For the downlink (DL) in particular, a time division duplex (TDD) configuration synonymous with massive MIMO deployments could mean only the uplink (UL) is usable in extreme cases. Therefore, it is of great interest to investigate the impact of mobility on massive MIMO performance and consider ways to combat the potential limitations. In a mobile scenario with moving cars and pedestrians, the massive MIMO channel is sampled across many points in space to build a picture of the overall user orthogonality, and the impact of both azimuth and elevation array configurations are considered. Temporal analysis is also conducted for vehicles moving up to 29km�h and real-time bit error rates (BERs) for both the UL and DL without power control are presented. For a 100 antenna system, it is found that the channel state information (CSI) update rate requirement may increase by 7 times when compared to an 8 antenna system, whilst the power control update rate could be decreased by at least 5 times relative to a single antenna system.

Connected through hyperedge HE-1 (induced by source paper "hardware distortion correlation has negligible impact on ul massive mimo spectral efficiency"):
  with members:
    - "massive mimo has unlimited capacity"
    - "can hardware distortion correlation be neglected when analyzing uplink se in massive mimo"
    - "out of band radiation from antenna arrays clarified"
    - "spatial characteristics of distortion radiated from antenna arrays with transceiver nonlinearities"
    - "throughput analysis of massive mimo uplink with low resolution adcs"
    - "achievable uplink rates for massive mimo with coarse quantization"
    - "impact of spatial filtering on distortion from low noise amplifiers in massive mimo base stations"
    - "quantized precoding for massive mu mimo"

Connected through hyperedge HE-2 (induced by source paper "efficient dsp and circuit architectures for massive mimo state of the art and future directions"):
  with members:
    - "beyond massive mimo the potential of data transmission with large intelligent surfaces"
    - "out of band radiation from antenna arrays clarified"
    - "spatial characteristics of distortion radiated from antenna arrays with transceiver nonlinearities"
    - "decentralized baseband processing for massive mu mimo systems"
    - "channel estimation and performance analysis of one bit massive mimo systems"
    - "on out of band emissions of quantized precoding in massive mu mimo ofdm"
    - "achievable uplink rates for massive mimo with coarse quantization"
    - "impact of spatial filtering on distortion from low noise amplifiers in massive mimo base stations"

Connected through hyperedge HE-3 (induced by source paper "edge and central cloud computing a perfect pairing for high energy efficiency and low latency"):
  with members:
    - "spectral and energy efficiency of uplink d2d underlaid massive mimo cellular networks"
    - "a survey on mobile edge computing the communication perspective"
    - "mobile edge computing a survey on architecture and computation offloading"
    - "joint offloading and computing optimization in wireless powered mobile edge computing systems"
    - "user association in 5g networks a survey and an outlook"
    - "energy efficient resource allocation for mobile edge computing based augmented reality applications"
    - "energy efficient resource allocation for mobile edge computation offloading"
    - "computation offloading decisions for reducing completion time"

Connected through hyperedge HE-4 (induced by source paper "measured channel hardening in an indoor multiband scenario"):
  with members:
    - "the world s first real time testbed for massive mimo design implementation and validation"
    - "no downlink pilots are needed in tdd massive mimo"
    - "massive mimo ten myths and one critical question"
    - "massive mimo performance evaluation based on measured propagation data"
    - "aspects of favorable propagation in massive mimo"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-5 (induced by source paper "massive mimo in sub 6 ghz and mmwave physical practical and use case differences"):
  with members:
    - "energy efficiency and asymptotic performance evaluation of beamforming structures in doubly massive mimo mmwave systems"
    - "out of band radiation from antenna arrays clarified"
    - "massive mimo performance evaluation based on measured propagation data"

Connected through hyperedge HE-6 (induced by source paper "achievable rates and training overheads for a measured los massive mimo channel"):
  with members:
    - "the world s first real time testbed for massive mimo design implementation and validation"
    - "effects of channel aging in massive mimo systems"

Connected through hyperedge HE-7 (induced by source paper "massive mimo performance tdd versus fdd what do measurements say"):
  with members:
    - "overview of full dimension mimo in lte advanced pro"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "on the number of rf chains and phase shifters and scheduling design with hybrid analog digital beamforming"
    - "hybrid digital and analog beamforming design for large scale antenna arrays"
    - "no downlink pilots are needed in tdd massive mimo"
    - "massive mimo ten myths and one critical question"
    - "reciprocity calibration for massive mimo proposal modeling and validation"
    - "hybrid beamforming for massive mimo a survey"

Connected through hyperedge HE-8 (induced by source paper "massive mimo for drone communications case studies and future directions"):
  with members:
    - "convolutionally coded snr adaptive transmission for low latency communications"
    - "understanding uav cellular communications from existing networks to massive mimo"
    - "mobile networks connected drones field trials simulations and design insights"
    - "the sky is not the limit lte for unmanned aerial vehicles"
    - "a telecom perspective on the internet of drones from lte advanced to 5g"
    - "a tutorial on uavs for wireless networks applications challenges and open problems"
    - "efficient dsp and circuit architectures for massive mimo state of the art and future directions"
    - "security privacy and safety evaluation of dynamic and static fleets of drones"

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)