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: "robust beamforming for security in mimo wiretap channels with imperfect csi"
  Abstract: In this paper, we investigate methods for reducing the likelihood that a message transmitted between two multi-antenna nodes is intercepted by an undetected eavesdropper. In particular, we focus on the judicious transmission of artificial interference to mask the desired signal at the time it is broadcast. Unlike previous work that assumes some prior knowledge of the eavesdropper's channel and focuses on maximizing secrecy capacity, we consider the case where no information regarding the eavesdropper is available, and we use signal-to-interference-plus-noise-ratio (SINR) as our performance metric. Specifically, we focus on the problem of maximizing the amount of power available to broadcast a jamming signal intended to hide the desired signal from a potential eavesdropper, while maintaining a prespecified SINR at the desired receiver. The jamming signal is designed to be orthogonal to the information signal when it reaches the desired receiver, assuming both the receiver and the eavesdropper employ optimal beamformers and possess exact channel state information (CSI). In practice, the assumption of perfect CSI at the transmitter is often difficult to justify. Therefore, we also study the resulting performance degradation due to the presence of imperfect CSI, and we present robust beamforming schemes that recover a large fraction of the performance in the perfect CSI case. Numerical simulations verify our analytical performance predictions, and illustrate the benefit of the robust beamforming schemes.

Connected through hyperedge HE-1 (induced by source paper "non orthogonal multiple access for 5g and beyond"):
  with members:
    - "downlink non orthogonal multiple access with limited feedback"
    - "optimal user scheduling and power allocation for millimeter wave noma systems"
    - "coordinated multi point comp transmission in downlink multi cell noma systems models and spectral efficiency performance"
    - "low complexity receiver for multi level polar coded modulation in non orthogonal multiple access"
    - "massive non orthogonal multiple access for cellular iot potentials and limitations"
    - "power domain non orthogonal multiple access noma in 5g systems potentials and challenges"
    - "modulation and multiple access for 5g networks"
    - "robust beamforming techniques for non orthogonal multiple access systems with bounded channel uncertainties"

Connected through hyperedge HE-2 (induced by source paper "secure swipt for directional modulation aided af relaying networks"):
  with members:
    - "spectral and energy efficient wireless powered iot networks noma or tdma"
    - "an overview of sustainable green 5g networks"
    - "a survey on wireless security technical challenges recent advances and future trends"
    - "secrecy wireless information and power transfer challenges and opportunities"
    - "relaying strategies for wireless powered mimo relay networks"
    - "to harvest and jam a paradigm of self sustaining friendly jammers for secure af relaying"
    - "relay selection improves the security reliability trade off in cognitive radio systems"
    - "noncoherent relaying in energy harvesting communication systems"

Connected through hyperedge HE-3 (induced by source paper "adaptive full duplex jamming receiver for secure d2d links in random networks"):
  with members:
    - "exploiting full duplex receivers for achieving secret communications in multiuser miso networks"
    - "secrecy outage analysis for downlink transmissions in the presence of randomly located eavesdroppers"
    - "modeling and analysis of cellular networks using stochastic geometry a tutorial"
    - "safeguarding decentralized wireless networks using full duplex jamming receivers"
    - "physical layer security in heterogeneous networks with jammer selection and full duplex users"
    - "physical layer security in heterogeneous cellular networks"
    - "a survey on device to device communication in cellular networks"
    - "passive self interference suppression for full duplex infrastructure nodes"

Connected through hyperedge HE-4 (induced by source paper "beamforming optimization for physical layer security in miso wireless networks"):
  with members:
    - "mimo beamforming for secure and energy efficient wireless communication"
    - "robust chance constrained optimization for power efficient and secure swipt systems"
    - "secrecy energy efficiency optimization for miso and siso communication networks"
    - "secrecy wireless information and power transfer with miso beamforming"
    - "toward energy efficient 5g wireless communications technologies"
    - "principles of physical layer security in multiuser wireless networks a survey"
    - "coordinated beamforming for multiuser miso interference channel under rate outage constraints"
    - "spatially selective artificial noise aided transmit optimization for miso multi eves secrecy rate maximization"

Connected through hyperedge HE-5 (induced by source paper "secure transmit antenna selection protocol for mimo noma networks over nakagami m channels"):
  with members:
    - "secrecy outage analysis for downlink transmissions in the presence of randomly located eavesdroppers"
    - "nonorthogonal multiple access in large scale underlay cognitive radio networks"
    - "on secrecy performance of antenna selection aided mimo systems against eavesdropping"
    - "secrecy sum rate maximization in non orthogonal multiple access"
    - "enhancing the physical layer security of non orthogonal multiple access in large scale networks"
    - "harvest then cooperate wireless powered cooperative communications"
    - "on the performance of non orthogonal multiple access in 5g systems with randomly deployed users"

Connected through hyperedge HE-6 (induced by source paper "robust secure transmission of using main lobe integration based leakage beamforming in directional modulation mu mimo systems"):
  with members:
    - "secrecy wireless information and power transfer challenges and opportunities"
    - "relay selection improves the security reliability trade off in cognitive radio systems"
    - "the secrecy capacity of the mimo wiretap channel"

Connected through hyperedge HE-7 (induced by source paper "secure communication over 1 2 1 networks"):
  with members:
    - "gaussian 1 2 1 networks capacity results for mmwave communications"
    - "on secure network coding with nonuniform or restricted wiretap sets"

Connected through hyperedge HE-8 (induced by source paper "a survey on mimo transmission with discrete input signals technical challenges advances and future trends"):
  with members:
    - "asymptotic performance analysis of a k hop amplify and forward relay mimo channel"
    - "iterative distributed minimum total mse approach for secure communications in mimo interference channels"
    - "asymptotic analysis of su mimo channels with transmitter noise and mismatched joint decoding"
    - "secure massive mimo transmission with an active eavesdropper"
    - "interference aligned space time transmission with diversity for the 2 times 2 x network"
    - "space time encoded miso broadcast channel with outdated csit an error rate and diversity performance analysis"
    - "high snr asymptotics of mutual information for discrete constellations with applications to bicm"
    - "differential distributed space time coding with imperfect synchronization in frequency selective 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)