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: "error bounds for uplink and downlink 3d localization in 5g mmwave systems"
  Abstract: Location-aware communication systems are expected to play a pivotal part in the next generation of mobile communication networks. Therefore, there is a need to understand the localization limits in these networks, particularly, using millimeter-wave technology (mmWave). Towards that, we address the uplink and downlink localization limits in terms of 3D position and orientation error bounds for mmWave multipath channels. We also carry out a detailed analysis of the dependence of the bounds of different systems parameters. Our key findings indicate that the uplink and downlink behave differently in two distinct ways. First of all, the error bounds have different scaling factors with respect to the number of antennas in the uplink and downlink. Secondly, uplink localization is sensitive to the orientation angle of the user equipment (UE), whereas downlink is not. Moreover, in the considered outdoor scenarios, the non-line-of-sight paths generally improve localization when a line-of-sight path exists. Finally, our numerical results show that mmWave systems are capable of localizing a UE with sub-meter position error, and sub-degree orientation error.

Connected through hyperedge HE-1 (induced by source paper "5g downlink multi beam signal design for los positioning"):
  with members:
    - "optimal precoders for tracking the aod and aoa of a mmwave path"
    - "performance limits of single anchor mm wave positioning"
    - "transmitter beam selection in millimeter wave mimo with in band position aiding"
    - "performance limits and geometric properties of array localization"

Connected through hyperedge HE-2 (induced by source paper "tracking position and orientation through millimeter wave lens mimo in 5g systems"):
  with members:
    - "optimal precoders for tracking the aod and aoa of a mmwave path"
    - "direct localization for massive mimo"
    - "multi user millimeter wave mimo with full dimensional lens antenna array"
    - "compressive channel estimation and tracking for large arrays in mm wave picocells"
    - "joint device positioning and clock synchronization in 5g ultra dense networks"
    - "frequency selective hybrid precoding for limited feedback millimeter wave systems"
    - "tracking angles of departure and arrival in a mobile millimeter wave channel"
    - "fingerprinting based positioning in distributed massive mimo systems"

Connected through hyperedge HE-3 (induced by source paper "optimal precoders for tracking the aod and aoa of a mmwave path"):
  with members:
    - "fast channel estimation for millimetre wave wireless systems using overlapped beam patterns"
    - "robust location aided beam alignment in millimeter wave massive mimo"
    - "modeling and analyzing millimeter wave cellular systems"
    - "transmitter beam selection in millimeter wave mimo with in band position aiding"
    - "hierarchical codebook design for beamforming training in millimeter wave communication"
    - "millimeter wave vehicular communication to support massive automotive sensing"
    - "channel estimation for hybrid architecture based wideband millimeter wave systems"
    - "hybrid rf and digital beamformer for cellular networks algorithms microwave architectures and measurements"

Connected through hyperedge HE-4 (induced by source paper "massive mimo based localization and mapping exploiting phase information of multipath components"):
  with members:
    - "a belief propagation algorithm for multipath based slam"
    - "a scalable belief propagation algorithm for radio signal based slam"
    - "direct localization for massive mimo"
    - "position and orientation estimation through millimeter wave mimo in 5g systems"
    - "measurement based wideband analysis of dynamic multipath propagation in vehicular communication scenarios"
    - "fingerprinting based positioning in distributed massive mimo systems"
    - "evaluation of position related information in multipath components for indoor positioning"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-5 (induced by source paper "single anchor two way localization bounds for 5g mmwave systems two protocols"):
  with members:
    - "position and orientation estimation through millimeter wave mimo in 5g systems"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "mitigating pilot contamination through location aware pilot assignment in massive mimo networks"
    - "spatial wireless channel prediction under location uncertainty"
    - "low power analog to digital conversion in millimeter wave systems impact of resolution and bandwidth on performance"
    - "what will 5g be"
    - "fundamental limits of wideband localization part ii cooperative networks"
    - "fundamental limits of wideband localization part i a general framework"

Connected through hyperedge HE-6 (induced by source paper "position and orientation estimation through millimeter wave mimo in 5g systems"):
  with members:
    - "direct localization for massive mimo"
    - "compressive channel estimation and tracking for large arrays in mm wave picocells"
    - "joint device positioning and clock synchronization in 5g ultra dense networks"
    - "cognitive indoor positioning and tracking using multipath channel information"
    - "frequency selective hybrid precoding for limited feedback millimeter wave systems"
    - "fingerprinting based positioning in distributed massive mimo systems"
    - "compressed sensing based multi user millimeter wave systems how many measurements are needed"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"

Connected through hyperedge HE-7 (induced by source paper "single anchor localization and orientation performance limits using massive arrays mimo vs beamforming"):
  with members:
    - "direct localization for massive mimo"
    - "performance limits and geometric properties of array localization"
    - "map aware models for indoor wireless localization systems an experimental study"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "massive mimo for next generation wireless systems"
    - "emerging technologies and research challenges for 5g wireless networks"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "fundamental limits of wideband localization part i a general framework"

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)