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: "mimo interference alignment over correlated channels with imperfect csi"
  Abstract: Interference alignment (IA), given uncorrelated channel components and perfect channel state information, obtains the maximum degrees of freedom in an interference channel. Little is known, however, about how the sum rate of IA behaves at finite transmit power, with imperfect channel state information, or antenna correlation. This paper provides an approximate closed-form signal-to-interference-plus-noise-ratio (SINR) expression for IA over multiple-input-multiple-output (MIMO) channels with imperfect channel state information and transmit antenna correlation. Assuming linear processing at the transmitters and zero-forcing receivers, random matrix theory tools are utilized to derive an approximation for the postprocessing SINR distribution of each stream for each user. Perfect channel knowledge and i.i.d. channel coefficients constitute special cases. This SINR distribution not only allows easy calculation of useful performance metrics like sum rate and symbol error rate, but also permits a realistic comparison of IA with other transmission techniques. More specifically, IA is compared with spatial multiplexing and beamforming and it is shown that IA may not be optimal for some performance criteria.

Connected through hyperedge HE-1 (induced by source paper "on the feasibility of interference alignment in compounded mimo broadcast channels with antenna correlation and mixed user classes"):
  with members:
    - "error performance of wireless powered cognitive relay networks with interference alignment"
    - "on the capacity of wireless powered cognitive relay network with interference alignment"
    - "feasibility of interference alignment for the mimo interference channel"
    - "bounds on eigenvalues of a spatial correlation matrix"
    - "why does the kronecker model result in misleading capacity estimates"
    - "on feasibility of interference alignment in mimo interference networks"
    - "interference alignment with analog channel state feedback"
    - "on feasibility of interference alignment in mimo interference networks"

Connected through hyperedge HE-2 (induced by source paper "on the sinr distribution of swipt mu mimo with antenna selection"):
  with members:
    - "multiuser mimo achievable rates with downlink training and channel state feedback"

Connected through hyperedge HE-3 (induced by source paper "cell edge aware precoding for downlink massive mimo cellular networks"):
  with members:
    - "distributed optimization of hierarchical small cell networks a gnep framework"
    - "massive mimo ten myths and one critical question"
    - "operating massive mimo in unlicensed bands for enhanced coexistence and spatial reuse"
    - "energy efficient design of mimo heterogeneous networks with wireless backhaul"
    - "a stochastic geometry framework for analyzing pairwise cooperative cellular networks"
    - "three practical aspects of massive mimo intermittent user activity pilot synchronism and asymmetric deployment"
    - "fractional pilot reuse in massive mimo systems"
    - "a tractable model for noncoherent joint transmission base station cooperation"

Connected through hyperedge HE-4 (induced by source paper "throughput region of spatially correlated interference packet networks"):
  with members:
    - "linear degrees of freedom of mimo broadcast channels with reconfigurable antennas in the absence of csit"
    - "optimal sum dof of the k user miso bc with current and delayed feedback"
    - "optimal dof of the k user broadcast channel with delayed and imperfect current csit"
    - "when does spatial correlation add value to delayed channel state information"
    - "two user erasure interference channels with local delayed csit"
    - "transmit beamforming for miso broadcast channels with statistical and delayed csit"
    - "informational bottlenecks in two unicast wireless networks with delayed csit"
    - "secure degrees of freedom region of the two user miso broadcast channel with alternating csit"

Connected through hyperedge HE-5 (induced by source paper "max min sinr in large scale single cell mu mimo asymptotic analysis and low complexity transceivers"):
  with members:
    - "large system analysis of the energy consumption distribution in multi user mimo systems with mobility"
    - "large system analysis of base station cooperation for power minimization"
    - "optimal multiuser transmit beamforming a difficult problem with a simple solution structure"
    - "linear precoding based on polynomial expansion large scale multi cell mimo systems"
    - "massive mimo for next generation wireless systems"
    - "joint beamforming and power control in coordinated multicell max min duality effective network and large system transition"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "large system analysis of linear precoding in correlated miso broadcast channels under limited feedback"

Connected through hyperedge HE-6 (induced by source paper "on channel reciprocity to activate uplink channel training for downlink data transmission"):
  with members:
    - "massive mimo performance with imperfect channel reciprocity and channel estimation error"
    - "short packet communications over multiple antenna rayleigh fading channels"
    - "what will 5g be"
    - "ultra reliable communication in 5g wireless systems"
    - "pilot contamination and precoding in multi cell tdd systems"

Connected through hyperedge HE-7 (induced by source paper "on channel reciprocity to activate uplink channel training for downlink wireless transmission in tactile internet applications"):
  with members:
    - "massive mimo performance with imperfect channel reciprocity and channel estimation error"
    - "short packet communications over multiple antenna rayleigh fading channels"
    - "ultra reliable communication in 5g wireless systems"
    - "pilot contamination and precoding in multi cell tdd systems"

Connected through hyperedge HE-8 (induced by source paper "breaking the interference barrier in dense wireless networks with interference alignment"):
  with members:
    - "ieee 802 11ax high efficiency wlans"
    - "mimo interference alignment in random access networks"

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)