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: "on the capacity and energy efficiency of training based transmissions over fading channels"
  Abstract: In this paper, the capacity and energy efficiency of training-based communication schemes employed for transmission over a-priori unknown Rayleigh block fading channels are studied. In these schemes, periodically transmitted training symbols are used at the receiver to obtain the minimum mean-square-error (MMSE) estimate of the channel fading coefficients. Initially, the case in which the product of the estimate error and transmitted signal is assumed to be Gaussian noise is considered. In this case, it is shown that bit energy requirements grow without bound as the signal-to-noise ratio (SNR) goes to zero, and the minimum bit energy is achieved at a nonzero SNR value below which one should not operate. The effect of the block length on both the minimum bit energy and the SNR value at which the minimum is achieved is investigated. Flash training and transmission schemes are analyzed and shown to improve the energy efficiency in the low-SNR regime. #R##N#In the second part of the paper, the capacity and energy efficiency of training-based schemes are investigated when the channel input is subject to peak power constraints. The capacity-achieving input structure is characterized and the magnitude distribution of the optimal input is shown to be discrete with a finite number of mass points. The capacity, bit energy requirements, and optimal resource allocation strategies are obtained through numerical analysis. The bit energy is again shown to grow without bound as SNR decreases to zero due to the presence of peakedness constraints. The improvements in energy efficiency when on-off keying with fixed peak power and vanishing duty cycle is employed are studied. Comparisons of the performances of training-based and noncoherent transmission schemes are provided.

Connected through hyperedge HE-1 (induced by source paper "pilot based channel estimation design in covert wireless communication"):
  with members:
    - "multi antenna covert communications in random wireless networks"
    - "low probability of detection communication opportunities and challenges"
    - "covert transmission with a self sustained relay"
    - "gaussian signalling for covert communications"
    - "achieving covert wireless communications using a full duplex receiver"
    - "multi hop routing in covert wireless networks"
    - "joint optimization of a uav s trajectory and transmit power for covert communications"
    - "covert wireless communications with channel inversion power control in rayleigh fading"

Connected through hyperedge HE-2 (induced by source paper "ultra reliable cooperative short packet communications with wireless energy transfer"):
  with members:
    - "ultra reliable short message cooperative relaying protocols under nakagami m fading"
    - "wireless powered communications with finite battery and finite blocklength"
    - "wireless powered relaying with finite block length codes"
    - "analysis of wireless communications with finite blocklength and imperfect channel knowledge"
    - "on wirelessly powered communications with short packets"
    - "wireless powered relays in cooperative communications time switching relaying protocols and throughput analysis"
    - "harvest then cooperate wireless powered cooperative communications"
    - "wireless networks with rf energy harvesting a contemporary survey"

Connected through hyperedge HE-3 (induced by source paper "performance analysis of ultra reliable short message decode and forward relaying protocols"):
  with members:
    - "network slicing for ultra reliable low latency communication in industry 4 0 scenarios"
    - "ultra reliable short message cooperative relaying protocols under nakagami m fading"
    - "on the performance of ultra reliable decode and forward relaying under the finite blocklength"
    - "wireless access for ultra reliable low latency communication urllc principles and building blocks"
    - "ultra reliable communication via optimum power allocation for type i arq in finite block length"
    - "energy efficient design for tactile internet"
    - "massive machine type communications in 5g physical and mac layer solutions"
    - "blocklength limited performance of relaying under quasi static rayleigh channels"

Connected through hyperedge HE-4 (induced by source paper "on an achievable rate of large rayleigh block fading mimo channels with no csi"):
  with members:
    - "large system analysis of joint channel and data estimation for mimo ds cdma systems"
    - "on the capacity of large mimo block fading channels"
    - "optimization of sequences in cdma systems a statistical mechanics approach"
    - "microscopic analysis for decoupling principle of linear vector channel"
    - "asymptotic analysis of general multiuser detectors in mimo ds cdma channels"
    - "analysis of cdma systems that are characterized by eigenvalue spectrum"
    - "randomly spread cdma asymptotics via statistical physics"

Connected through hyperedge HE-5 (induced by source paper "training optimization for energy harvesting communication systems"):
  with members:
    - "transmission with energy harvesting nodes in fading wireless channels optimal policies"
    - "optimal packet scheduling in an energy harvesting communication system"
    - "adaptive spatial intercell interference cancellation in multicell wireless networks"

Connected through hyperedge HE-6 (induced by source paper "performance analysis of cognitive radio systems under qos constraints and channel uncertainty"):
  with members:
    - "cognitive radio transmission under qos constraints and interference limitations"
    - "ergodic capacity analysis in cognitive radio systems under channel uncertainty"
    - "effective capacity analysis of cognitive radio channels for quality of service provisioning"

Connected through hyperedge HE-7 (induced by source paper "mutual information of iid complex gaussian signals on block rayleigh faded channels"):
  with members:
    - "optimum pilot overhead in wireless communication a unified treatment of continuous and block fading channels"
    - "what is the value of joint processing of pilots and data in block fading channels"
    - "gallager s exponent for mimo channels a reliability rate tradeoff"

Connected through hyperedge HE-8 (induced by source paper "energy efficiency in the low snr regime under queueing constraints and channel uncertainty"):
  with members:
    - "the impact of qos constraints on the energy efficiency of fixed rate wireless transmissions"
    - "analysis of energy efficiency in fading channels under qos constraints"
    - "capacity of sparse multipath channels in the ultra wideband regime"
    - "channel uncertainty in ultra wideband communication 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)