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: "single user beamforming in large scale miso systems with per antenna constant envelope constraints the doughnut channel"
  Abstract: Large antenna arrays at the base station (BS) has recently been shown to achieve remarkable intra-cell interference suppression at low complexity. However, building large arrays in practice, would require the use of power-efficient RF amplifiers, which generally have poor linearity characteristics and hence would require the use of input signals with a very small peak-to-average power ratio (PAPR). In this paper, we consider the single-user Multiple-Input Single-Output (MISO) downlink channel for the case where the BS antennas are constrained to transmit signals having constant envelope (CE). We show that, with per-antenna CE transmission the effective channel seen by the receiver is a SISO AWGN channel with its input constrained to lie in a doughnut-shaped region. For single-path direct-line-of-sight (DLOS) and general i.i.d. fading channels, analysis of the effective doughnut channel shows that under a per-antenna CE input constraint, i) compared to an average-only total transmit power constrained MISO channel, the extra total transmit power required to achieve a desired information rate is small and bounded, ii) with N base station antennas an O(N) array power gain is achievable, and iii) for a desired information rate, using power-efficient amplifiers with CE inputs would require significantly less total transmit power when compared to using highly linear (power-inefficient) amplifiers with high PAPR inputs.

Connected through hyperedge HE-1 (induced by source paper "quantized constant envelope precoding with psk and qam signaling"):
  with members:
    - "1 bit massive mu mimo precoding in vlsi"
    - "branch and bound precoding for multiuser mimo systems with 1 bit quantization"
    - "quantized precoding for multi antenna downlink channels with magiq"
    - "nonlinear precoding for phase quantized constant envelope massive mu mimo ofdm"
    - "linear precoding with low resolution dacs for massive mu mimo ofdm downlink"
    - "psk precoding in multi user miso systems"
    - "massive mimo downlink 1 bit precoding with linear programming for psk signaling"
    - "an efficient manifold algorithm for constructive interference based constant envelope precoding"

Connected through hyperedge HE-2 (induced by source paper "intelligent reflecting surface enhanced wireless network via joint active and passive beamforming"):
  with members:
    - "beamforming optimization for wireless network aided by intelligent reflecting surface with discrete phase shifts"
    - "weighted sum power maximization for intelligent reflecting surface aided swipt"
    - "intelligent reflecting surface assisted secrecy communication via joint beamforming and jamming"
    - "towards smart and reconfigurable environment intelligent reflecting surface aided wireless network"
    - "achievable rate maximization by passive intelligent mirrors"
    - "beyond massive mimo the potential of data transmission with large intelligent surfaces"
    - "beamforming optimization for intelligent reflecting surface with discrete phase shifts"
    - "intelligent reflecting surface enhanced wireless network joint active and passive beamforming design"

Connected through hyperedge HE-3 (induced by source paper "a framework for one bit and constant envelope precoding over multiuser massive miso channels"):
  with members:
    - "one bit massive mimo precoding via a minimum symbol error probability design"
    - "minimum symbol error rate based constant envelope precoding for multiuser massive miso downlink"
    - "quantized constant envelope precoding with psk and qam signaling"
    - "multiuser one bit massive mimo precoding under mpsk signaling"
    - "mse optimal 1 bit precoding for multiuser mimo via branch and bound"
    - "one bit precoding and constellation range design for massive mimo with qam signaling"
    - "accelerated gradient descent escapes saddle points faster than gradient descent"
    - "nonlinear precoding for phase quantized constant envelope massive mu mimo ofdm"

Connected through hyperedge HE-4 (induced by source paper "symbol level and multicast precoding for multiuser multiantenna downlink a survey classification and challenges"):
  with members:
    - "channel estimation and performance analysis of one bit massive mimo systems"
    - "an overview on resource allocation techniques for multi user mimo systems"
    - "spatio temporal waveform design for multiuser massive mimo downlink with 1 bit receivers"
    - "joint beamforming and broadcasting in massive mimo"
    - "coordinate update algorithms for robust power loading for the mu miso downlink with outage constraints"
    - "energy efficient symbol level precoding in multiuser miso based on relaxed detection region"
    - "robust transmission in downlink multiuser miso systems a rate splitting approach"
    - "adaptive pilot clustering in heterogeneous massive mimo networks"

Connected through hyperedge HE-5 (induced by source paper "finite alphabet precoding for massive mu mimo with low resolution dacs"):
  with members:
    - "energy efficiency of mmwave massive mimo precoding with low resolution dacs"
    - "multipair massive mimo relaying systems with one bit adc s and dac s"
    - "1 bit massive mu mimo precoding in vlsi"
    - "throughput analysis of massive mimo uplink with low resolution adcs"
    - "channel estimation and performance analysis of one bit massive mimo systems"
    - "full duplex massive mimo relaying systems with low resolution adcs"
    - "massive mu mimo ofdm downlink with one bit dacs and linear precoding"
    - "bayes optimal joint channel and data estimation for massive mimo with low precision adcs"

Connected through hyperedge HE-6 (induced by source paper "energy efficient transceiver design for hybrid sub array architecture mimo systems"):
  with members:
    - "secure massive mimo systems with limited rf chains"
    - "wireless powered communication opportunities and challenges"
    - "limited feedback hybrid precoding for multi user millimeter wave systems"
    - "iterative eigenvalue decomposition and multipath grouping tx rx joint beamformings for millimeter wave communications"
    - "channel estimation and hybrid precoding for millimeter wave cellular systems"
    - "what will 5g be"
    - "millimeter wave cellular wireless networks potentials and challenges"
    - "spatially sparse precoding in millimeter wave mimo systems"

Connected through hyperedge HE-7 (induced by source paper "m qam precoder design for mimo directional modulation transceivers"):
  with members:
    - "energy efficient symbol level precoding in multiuser miso based on relaxed detection region"
    - "directional modulation via symbol level precoding a way to enhance security"
    - "constructive interference through symbol level precoding for multi level modulation"
    - "constructive multiuser interference in symbol level precoding for the miso downlink channel"
    - "exploiting known interference as green signal power for downlink beamforming optimization"

Connected through hyperedge HE-8 (induced by source paper "an efficient manifold algorithm for constructive interference based constant envelope precoding"):
  with members:
    - "interference exploitation in full duplex communications trading interference power for both uplink and downlink power savings"
    - "exploiting known interference as green signal power for downlink beamforming optimization"
    - "massive mimo for next generation wireless systems"
    - "manopt a matlab toolbox for optimization on manifolds"
    - "per antenna constant envelope precoding for large multi user mimo 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)