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: "mimo precoding with x and y codes"
  Abstract: We consider a time division duplex (TDD) $n_t \times n_r$ multiple-input multiple-output (MIMO) system with channel state information (CSI) at both the transmitter and receiver. We propose X- and Y-Codes to achieve high multiplexing and diversity gains at low complexity. The proposed precoding schemes are based upon the singular value decomposition (SVD) of the channel matrix which transforms the MIMO channel into parallel subchannels. Then X- and Y-Codes are used to improve the diversity gain by pairing the subchannels, prior to SVD precoding. In particular, the subchannels with good diversity are paired with those having low diversity gains. Hence, a pair of channels is jointly encoded using a $2 \times 2$ real matrix, which is fixed {\em a priori} and does not change with each channel realization. For X-Codes these matrices are 2-dimensional rotation matrices parameterized by a single angle, while for Y-Codes, these matrices are 2-dimensional upper left triangular matrices. The complexity of the maximum likelihood decoding (MLD) for both X- and Y-Codes is low. Specifically, the decoding complexity of Y-Codes is the same as that of a scalar channel. Moreover, we propose X-, Y-Precoders with the same structure as X-, Y-Codes, but the encoding matrices adapt to each channel realization. The optimal encoding matrices for X-, Y-Codes/Precoders are derived analytically. Finally, it is observed that X-Codes/Precoders perform better for well-conditioned channels, while Y-Codes/Precoders perform better for ill-conditioned channels, when compared to other precoding schemes in the literature.

Connected through hyperedge HE-1 (induced by source paper "steepest gradient based orthogonal precoder for integer forcing mimo"):
  with members:
    - "boosted kz and lll algorithms"
    - "efficient integer coefficient search for compute and forward"
    - "encoding and indexing of lattice codes"
    - "an efficient optimal algorithm for the successive minima problem"
    - "full diversity unitary precoded integer forcing"
    - "precoded integer forcing universally achieves the mimo capacity to within a constant gap"
    - "integer forcing mimo linear receivers based on lattice reduction"
    - "integer forcing linear receivers"

Connected through hyperedge HE-2 (induced by source paper "antenna arrays for line of sight massive mimo half wavelength is not enough"):
  with members:
    - "massive mimo ten myths and one critical question"
    - "space constrained massive mimo hitting the wall of favorable propagation"
    - "massive mimo performance evaluation based on measured propagation data"
    - "aspects of favorable propagation in massive mimo"
    - "massive mimo for next generation wireless systems"
    - "optimal design of energy efficient multi user mimo systems is massive mimo the answer"
    - "five disruptive technology directions for 5g"
    - "scaling up mimo opportunities and challenges with very large arrays"

Connected through hyperedge HE-3 (induced by source paper "full diversity unitary precoded integer forcing"):
  with members:
    - "phase precoded compute and forward with partial feedback"
    - "phase precoding for the compute and forward protocol"
    - "precoded integer forcing universally achieves the mimo capacity to within a constant gap"
    - "an algebraic approach to physical layer network coding"
    - "on complex lll algorithm for integer forcing linear receivers"
    - "integer forcing mimo linear receivers based on lattice reduction"
    - "diversity of mimo linear precoding"
    - "integer forcing linear receivers"

Connected through hyperedge HE-4 (induced by source paper "oblivious transfer over wireless channels"):
  with members:
    - "the oblivious transfer capacity of the wiretapped binary erasure channel"
    - "information spectrum approach to strong converse theorems for degraded wiretap channels"
    - "semantically secure lattice codes for the gaussian wiretap channel"
    - "achieving the secrecy capacity of wiretap channels using polar codes"
    - "precoding by pairing subchannels to increase mimo capacity with discrete input alphabets"
    - "the secrecy capacity of the mimo wiretap channel"
    - "commitment capacity of discrete memoryless channels"

Connected through hyperedge HE-5 (induced by source paper "massive mimo performance evaluation based on measured propagation data"):
  with members:
    - "aspects of favorable propagation in massive mimo"
    - "massive mimo for next generation wireless systems"
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "diversity limits of compact broadband multi antenna systems"
    - "energy and spectral efficiency of very large multiuser mimo systems"

Connected through hyperedge HE-6 (induced by source paper "on precoding for constant k user mimo gaussian interference channel with finite constellation inputs"):
  with members:
    - "real interference alignment exploiting the potential of single antenna systems"
    - "linear precoder design for mimo interference channels with finite alphabet signaling"
    - "interference alignment for the mimo interference channel with delayed local csit"
    - "two user gaussian interference channel with finite constellation input and fdma"
    - "achievable rates in two user interference channels with finite inputs and very strong interference"
    - "interference alignment for the k user mimo interference channel"
    - "capacity regions and sum rate capacities of vector gaussian interference channels"
    - "linear transceiver design for interference alignment complexity and computation"

Connected through hyperedge HE-7 (induced by source paper "bit interleaved coded multiple beamforming with perfect coding"):
  with members:
    - "precoding by pairing subchannels to increase mimo capacity with discrete input alphabets"
    - "reduced complexity decoding for bit interleaved coded multiple beamforming with constellation precoding"
    - "golden coded multiple beamforming"
    - "constellation precoded beamforming"
    - "constellation precoded multiple beamforming"
    - "reduced complexity sphere decoding"
    - "bit interleaved coded multiple beamforming with constellation precoding"
    - "diversity analysis of bit interleaved coded multiple beamforming"

Connected through hyperedge HE-8 (induced by source paper "precoding for outage probability minimization on block fading channels"):
  with members:
    - "high snr asymptotics of mutual information for discrete constellations with applications to bicm"
    - "low density graph codes for coded cooperation on slow fading relay channels"
    - "precoding by pairing subchannels to increase mimo capacity with discrete input alphabets"
    - "space time coding techniques with bit interleaved coded modulations for mimo block fading channels"
    - "mutual information and minimum mean square error in gaussian 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)