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: "sum rate maximizing multigroup multicast beamforming under per antenna power constraints"
  Abstract: A multi-antenna transmitter that conveys independent sets of common data to distinct groups of users is herein considered, a model known as physical layer multicasting to multiple co-channel groups. In the recently proposed context of per-antenna power constrained multigroup multicasting, the present work focuses on a novel system design that aims at maximizing the total achievable throughput. Towards increasing the system sum rate, the available power resources need to be allocated to well conditioned groups of users. A detailed solution to tackle the elaborate sum rate maximizing, multigroup multicast problem, under per-antenna power constraints is therefore derived. Numerical results are presented to quantify the gains of the proposed algorithm over heuristic solutions. The solution is applied to rayleigh as well as Vandermonde channels. The latter case is typically realised in uniform linear array transmitters operating in the far field, where line-of-sight conditions are realized. In this setting, a sensitivity analysis with respect to the angular separation of co-group users is included. Finally, a simple scenario providing important intuitions for the sum rate maximizing multigroup multicast solutions is elaborated.

Connected through hyperedge HE-1 (induced by source paper "precoding in multibeam satellite communications present and future challenges"):
  with members:
    - "multicast multigroup precoding and user scheduling for frame based satellite communications"
    - "frame based precoding in satellite communications a multicast approach"
    - "full frequency reuse multibeam satcoms frame based precoding and user scheduling"
    - "weighted fair multicast multigroup beamforming under per antenna power constraints"
    - "gateway switching in q v band satellite feeder links"
    - "multi gateway cooperation in multibeam satellite systems"

Connected through hyperedge HE-2 (induced by source paper "distributed coordinated beamforming for multi cell multigroup multicast systems"):
  with members:
    - "multicast multigroup beamforming under per antenna power constraints"
    - "weighted fair multicast multigroup beamforming under per antenna power constraints"
    - "coordinated multicast beamforming in multicell networks"
    - "distributed multicell beamforming design approaching pareto boundary with max min fairness"

Connected through hyperedge HE-3 (induced by source paper "a rate splitting strategy for max min fair multigroup multicasting"):
  with members:
    - "sum rate maximization for linearly precoded downlink multiuser miso systems with partial csit a rate splitting approach"
    - "robust transmission in downlink multiuser miso systems a rate splitting approach"
    - "multicast multigroup beamforming for per antenna power constrained large scale arrays"
    - "weighted fair multicast multigroup beamforming under per antenna power constraints"

Connected through hyperedge HE-4 (induced by source paper "multicast multigroup precoding and user scheduling for frame based satellite communications"):
  with members:
    - "optimal multiuser transmit beamforming a difficult problem with a simple solution structure"
    - "frame based precoding in satellite communications a multicast approach"
    - "multicast multigroup beamforming under per antenna power constraints"
    - "weighted fair multicast multigroup beamforming under per antenna power constraints"
    - "user scheduling for coordinated dual satellite systems with linear precoding"
    - "multi gateway cooperation in multibeam satellite systems"
    - "generic optimization of linear precoding in multibeam satellite systems"

Connected through hyperedge HE-5 (induced by source paper "coordinated multicasting with opportunistic user selection in multicell wireless systems"):
  with members:
    - "weighted fair multicast multigroup beamforming under per antenna power constraints"
    - "coordinated beamforming for multiuser miso interference channel under rate outage constraints"
    - "coordinated multicast beamforming in multicell networks"
    - "precoder design for physical layer multicasting"

Connected through hyperedge HE-6 (induced by source paper "power allocation for precoding in large scale mu mimo systems with per antenna constraint"):
  with members:
    - "normalized volume of hyperball in complex grassmann manifold and its application in large scale mu mimo communication systems"
    - "massive mimo for next generation wireless systems"
    - "designing multi user mimo for energy efficiency when is massive mimo the answer"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-7 (induced by source paper "frame based precoding in satellite communications a multicast approach"):
  with members:
    - "multicast multigroup beamforming under per antenna power constraints"
    - "weighted fair multicast multigroup beamforming under per antenna power constraints"
    - "mmse performance analysis of generalized multibeam satellite channels"
    - "generic optimization of linear precoding in multibeam satellite systems"

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)