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: "secure beamforming for mimo broadcasting with wireless information and power transfer"
  Abstract: This paper considers a basic MIMO information-energy (I-E) broadcast system, where a multi-antenna transmitter transmits information and energy simultaneously to a multi-antenna information receiver and a dual-functional multi-antenna energy receiver which is also capable of decoding information. Due to the open nature of wireless medium and the dual purpose of information and energy transmission, secure information transmission while ensuring efficient energy harvesting is a critical issue for such a broadcast system. Assuming that physical layer security techniques are applied to the system to ensure secure transmission from the transmitter to the information receiver, we study beamforming design to maximize the achievable secrecy rate subject to a total power constraint and an energy harvesting constraint. First, based on semidefinite relaxation, we propose global optimal solutions to the secrecy rate maximization (SRM) problem in the single-stream case and a specific full-stream case where the difference of Gram matrices of the channel matrices is positive semidefinite. Then, we propose a simple iterative algorithm named inexact block coordinate descent (IBCD) algorithm to tackle the SRM problem of general case with arbitrary number of streams. We proves that the IBCD algorithm can monotonically converge to a Karush-Kuhn-Tucker (KKT) solution to the SRM problem. Furthermore, we extend the IBCD algorithm to the joint beamforming and artificial noise design problem. Finally, simulations are performed to validate the performance of the proposed beamforming algorithms.

Connected through hyperedge HE-1 (induced by source paper "robust beamforming and jamming for enhancing the physical layer security of full duplex radios"):
  with members:
    - "a new design paradigm for secure full duplex multiuser systems"
    - "iterative distributed minimum total mse approach for secure communications in mimo interference channels"
    - "detecting byzantine attacks without clean reference"
    - "secrecy transmit beamforming for heterogeneous networks"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "security versus reliability analysis of opportunistic relaying"
    - "in band full duplex wireless challenges and opportunities"
    - "robust secure transmission in miso channels based on worst case optimization"

Connected through hyperedge HE-2 (induced by source paper "robust energy efficient beamforming in misome swipt systems with proportional secrecy rate"):
  with members:
    - "robust secrecy energy efficient beamforming in misome swipt systems with proportional fairness"
    - "rf based energy harvesting in decode and forward relaying systems ergodic and outage capacities"
    - "secure beamforming in full duplex swipt systems with loopback self interference cancellation"
    - "large scale multiantenna multisine wireless power transfer"
    - "dynamic cross layer beamforming in hybrid powered communication systems with harvest use trade strategy"
    - "joint optimization of power and data transfer in multiuser mimo systems"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "network densification in 5g from the short range communications perspective"

Connected through hyperedge HE-3 (induced by source paper "robust secrecy energy efficient beamforming in misome swipt systems with proportional fairness"):
  with members:
    - "secure beamforming in full duplex swipt systems with loopback self interference cancellation"
    - "robust energy efficient beamforming in misome swipt systems with proportional secrecy rate"
    - "large scale multiantenna multisine wireless power transfer"
    - "robust resource allocation for mimo wireless powered communication networks based on a non linear eh model"
    - "network densification in 5g from the short range communications perspective"
    - "wireless information and power transfer nonlinearity waveform design and rate energy tradeoff"
    - "an overview of sustainable green 5g networks"
    - "communications and signals design for wireless power transmission"

Connected through hyperedge HE-4 (induced by source paper "spectral efficiency optimization for millimeter wave multiuser mimo systems"):
  with members:
    - "hybrid beamforming via the kronecker decomposition for the millimeter wave massive mimo systems"
    - "penalty dual decomposition method for nonsmooth nonconvex optimization"
    - "joint source relay design for full duplex mimo af relay systems"
    - "an overview of signal processing techniques for millimeter wave mimo systems"
    - "hybrid digital and analog beamforming design for large scale antenna arrays"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"
    - "near optimal hybrid processing for massive mimo systems via matrix decomposition"
    - "hybrid block diagonalization for massive multiuser mimo systems"

Connected through hyperedge HE-5 (induced by source paper "secure beamforming in full duplex swipt systems with loopback self interference cancellation"):
  with members:
    - "probabilistically robust swipt for secrecy misome systems"
    - "secure beamforming in full duplex swipt systems"
    - "transceiver design to maximize the weighted sum secrecy rate in full duplex swipt systems"
    - "multi objective optimization for robust power efficient and secure full duplex wireless communication systems"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "secure and green swipt in distributed antenna networks with limited backhaul capacity"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "design and characterization of a full duplex multiantenna system for wifi networks"

Connected through hyperedge HE-6 (induced by source paper "experiment modeling and analysis of wireless powered sensor network for energy neutral power management"):
  with members:
    - "wireless charging technologies fundamentals standards and network applications"
    - "resource allocation in wireless networks with rf energy harvesting and transfer"
    - "wireless powered communication opportunities and challenges"
    - "harvest then cooperate wireless powered cooperative communications"
    - "full duplex wireless powered communication network with energy causality"

Connected through hyperedge HE-7 (induced by source paper "energy harvesting fairness in an aided secure mu mimo swipt systems with cooperative jammer"):
  with members:
    - "beamforming and power splitting designs for an aided secure multi user mimo swipt systems"
    - "robust beamforming for secure communication in systems with wireless information and power transfer"
    - "secure communication with a wireless powered friendly jammer"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

Connected through hyperedge HE-8 (induced by source paper "an aided secure transmission in multi user mimo swipt systems"):
  with members:
    - "beamforming and power splitting designs for an aided secure multi user mimo swipt systems"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"
    - "mimo broadcasting for simultaneous wireless information and power transfer"

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)