human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "the practical challenges of interference alignment"):
  Abstract: Interference alignment (IA) is a revolutionary wireless transmission strategy that reduces the impact of interference. The idea of interference alignment is to coordinate multiple transmitters so that their mutual interference aligns at the receivers, facilitating simple interference cancellation techniques. Since IA's inception, researchers have investigated its performance and proposed improvements, verifying IA's ability to achieve the maximum degrees of freedom (an approximation of sum capacity) in a variety of settings, developing algorithms for determining alignment solutions, and generalizing transmission strategies that relax the need for perfect alignment but yield better performance. This article provides an overview of the concept of interference alignment as well as an assessment of practical issues including performance in realistic propagation environments, the role of channel state information at the transmitter, and the practicality of interference alignment in large networks.

Includes members:
  Member "on the degrees of freedom achievable through interference alignment in a mimo interference channel":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "centralized and decentralized cache aided interference management in heterogeneous parallel channels")
  Member "adaptive beamforming in interference networks via bi directional training":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "optimizing the mimo cellular downlink multiplexing diversity or interference nulling")
  Member "user partitioning for less overhead in mimo interference channels":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "distributed long term base station clustering in cellular networks using coalition formation")
  Member "cooperative algorithms for mimo interference channels":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "the capacity and optimal signaling for gaussian mimo channels under interference constraints full version")
  Member "interference alignment with analog channel state feedback":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "on the feasibility of interference alignment in compounded mimo broadcast channels with antenna correlation and mixed user classes")
  Member "interference alignment with limited feedback":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "opportunistic downlink interference alignment for multi cell mimo networks")

Question: Please tell me which class the source paper 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)