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: "a novel power allocation scheme for two user gmac with finite input constellations"
  Abstract: Constellation Constrained (CC) capacity regions of two-user Gaussian Multiple Access Channels (GMAC) have been recently reported, wherein an appropriate angle of rotation between the constellations of the two users is shown to enlarge the CC capacity region. We refer to such a scheme as the Constellation Rotation (CR) scheme. In this paper, we propose a novel scheme called the Constellation Power Allocation (CPA) scheme, wherein the instantaneous transmit power of the two users are varied by maintaining their average power constraints. We show that the CPA scheme offers CC sum capacities equal (at low SNR values) or close (at high SNR values) to those offered by the CR scheme with reduced decoding complexity for QAM constellations. We study the robustness of the CPA scheme for random phase offsets in the channel and unequal average power constraints for the two users. With random phase offsets in the channel, we show that the CC sum capacity offered by the CPA scheme is more than the CR scheme at high SNR values. With unequal average power constraints, we show that the CPA scheme provides maximum gain when the power levels are close, and the advantage diminishes with the increase in the power difference.

Connected through hyperedge HE-1 (induced by source paper "uplink non orthogonal multiple access with finite alphabet inputs"):
  with members:
    - "on non orthogonal multiple access with finite alphabet inputs in z channels"
    - "a survey on non orthogonal multiple access for 5g networks research challenges and future trends"
    - "capacity comparison between mimo noma and mimo oma with multiple users in a cluster"
    - "joint rate control and power allocation for non orthogonal multiple access systems"
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "relay selection for cooperative noma"
    - "quadrature amplitude modulation division for multiuser miso broadcast channels"
    - "non orthogonal multiple access in multi cell networks theory performance and practical challenges"

Connected through hyperedge HE-2 (induced by source paper "on non orthogonal multiple access with finite alphabet inputs in z channels"):
  with members:
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "relay selection for cooperative noma"
    - "a survey of downlink non orthogonal multiple access for 5g wireless communication networks"
    - "non orthogonal multiple access in multi cell networks theory performance and practical challenges"
    - "on the gaussian many to one x channel"
    - "cooperative non orthogonal multiple access with simultaneous wireless information and power transfer"
    - "linear precoding for the mimo multiple access channel with finite alphabet inputs and statistical csi"
    - "what will 5g be"

Connected through hyperedge HE-3 (induced by source paper "linear precoding for the mimo multiple access channel with finite alphabet inputs and statistical csi"):
  with members:
    - "performance limits of massive mimo systems based on bayes optimal inference"
    - "massive mimo for next generation wireless systems"
    - "transmit designs for the mimo broadcast channel with statistical csi"
    - "large system analysis of correlated mimo multiple access channels with arbitrary signaling in the presence of interference"
    - "linear precoder design for mimo interference channels with finite alphabet signaling"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "a deterministic equivalent for the analysis of correlated mimo multiple access channels"
    - "the dynamics of message passing on dense graphs with applications to compressed sensing"

Connected through hyperedge HE-4 (induced by source paper "linear mimo precoding in jointly correlated fading multiple access channels with finite alphabet signaling"):
  with members:
    - "linear precoder design for mimo interference channels with finite alphabet signaling"
    - "hessian and concavity of mutual information differential entropy and entropy power in linear vector gaussian channels"
    - "vector precoding for wireless mimo systems and its replica analysis"
    - "randomly spread cdma asymptotics via statistical physics"
    - "mutual information and minimum mean square error in gaussian channels"

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)