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: "performance improvement of iterative multiuser detection for large sparsely spread cdma systems by spatial coupling"
  Abstract: Kudekar  et al.  proved that the belief-propagation (BP) performance for low-density parity check codes can be boosted up to the maximum  a posteriori  (MAP) performance by spatial coupling. In this paper, spatial coupling is applied to sparsely spread code-division multiple-access systems to improve the performance of iterative multiuser detection based on BP. Two iterative receivers based on BP are considered: 1) one receiver is based on exact BP and 2) the other on an approximate BP with Gaussian approximation. The performance of the two BP receivers is evaluated via density evolution (DE) in the dense limit after taking the large-system limit, in which the number of users and the spreading factor tend to infinity while their ratio is kept constant. The two BP receivers are shown to achieve the same performance as each other in these limits. Furthermore, taking a continuum limit for the obtained DE equations implies that the performance of the two BP receivers can be improved up to the performance achieved by the symbol-wise MAP detection, called individually optimal detection, via spatial coupling. Numerical simulations show that spatial coupling can provide a significant improvement in bit-error rate for finite-sized systems especially in the region of high system loads.

Connected through hyperedge HE-1 (induced by source paper "rigorous dynamics of expectation propagation based signal recovery from unitarily invariant measurements"):
  with members:
    - "the mutual information in random linear estimation beyond i i d matrices"
    - "the replica symmetric prediction for compressed sensing with gaussian matrices is exact"
    - "expectation consistent approximate inference generalizations and convergence"
    - "the mutual information in random linear estimation"
    - "generalized turbo signal recovery for nonlinear measurements and orthogonal sensing matrices"
    - "turbo compressed sensing with partial dft sensing matrix"
    - "s amp approximate message passing for general matrix ensembles"
    - "signal recovery using expectation consistent approximation for linear observations"

Connected through hyperedge HE-2 (induced by source paper "a generalization of threshold saturation application to spatially coupled bicm id"):
  with members:
    - "iterative multiuser detection and decoding with spatially coupled interleaving"
    - "thresholds of spatially coupled systems via lyapunov s method"
    - "a simple proof of threshold saturation for coupled scalar recursions"
    - "chains of mean field models"
    - "a phenomenological study on threshold improvement via spatial coupling"
    - "wave like solutions of general one dimensional spatially coupled systems"
    - "information theoretically optimal compressed sensing via spatial coupling and approximate message passing"
    - "threshold saturation via spatial coupling why convolutional ldpc ensembles perform so well over the bec"

Connected through hyperedge HE-3 (induced by source paper "accelerating iterative detection for spatially coupled systems by collaborative training"):
  with members:
    - "chains of mean field models"
    - "a phenomenological study on threshold improvement via spatial coupling"
    - "information theoretically optimal compressed sensing via spatial coupling and approximate message passing"
    - "threshold saturation via spatial coupling why convolutional ldpc ensembles perform so well over the bec"
    - "multiple access demodulation in the lifted signal graph with spatial coupling"
    - "connecting spatially coupled ldpc code chains"
    - "improvement of bp based cdma multiuser detection by spatial coupling"
    - "the effect of spatial coupling on compressive sensing"

Connected through hyperedge HE-4 (induced by source paper "a potential theory of general spatially coupled systems via a continuum approximation"):
  with members:
    - "a simple proof of threshold saturation for coupled scalar recursions"
    - "chains of mean field models"
    - "a phenomenological study on threshold improvement via spatial coupling"
    - "wave like solutions of general one dimensional spatially coupled systems"
    - "information theoretically optimal compressed sensing via spatial coupling and approximate message passing"
    - "spatially coupled mackay neal codes and hsu anastasopoulos codes"
    - "threshold saturation via spatial coupling why convolutional ldpc ensembles perform so well over the bec"
    - "multiple access demodulation in the lifted signal graph with spatial coupling"

Connected through hyperedge HE-5 (induced by source paper "iterative multiuser detection and decoding with spatially coupled interleaving"):
  with members:
    - "threshold saturation via spatial coupling why convolutional ldpc ensembles perform so well over the bec"
    - "multiple access demodulation in the lifted signal graph with spatial coupling"
    - "improvement of bp based cdma multiuser detection by spatial coupling"
    - "randomly spread cdma asymptotics via statistical physics"

Connected through hyperedge HE-6 (induced by source paper "coupling data transmission for multiple access communications"):
  with members:
    - "proof of threshold saturation for spatially coupled sparse superposition codes"
    - "a simple proof of maxwell saturation for coupled scalar recursions"
    - "a simple proof of threshold saturation for coupled scalar recursions"
    - "spatially coupled ensembles universally achieve capacity under belief propagation"
    - "a phenomenological study on threshold improvement via spatial coupling"
    - "information theoretically optimal compressed sensing via spatial coupling and approximate message passing"
    - "spatially coupled quasi cyclic quantum ldpc codes"
    - "threshold saturation via spatial coupling why convolutional ldpc ensembles perform so well over the bec"

Connected through hyperedge HE-7 (induced by source paper "coupling data transmission for capacity achieving multiple access communications"):
  with members:
    - "a simple proof of threshold saturation for coupled scalar recursions"
    - "spatially coupled ensembles universally achieve capacity under belief propagation"
    - "a phenomenological study on threshold improvement via spatial coupling"
    - "wave like solutions of general one dimensional spatially coupled systems"
    - "information theoretically optimal compressed sensing via spatial coupling and approximate message passing"
    - "spatially coupled quasi cyclic quantum ldpc codes"
    - "threshold saturation via spatial coupling why convolutional ldpc ensembles perform so well over the bec"
    - "multiple access demodulation in the lifted signal graph with spatial coupling"

Connected through hyperedge HE-8 (induced by source paper "a phenomenological study on threshold improvement via spatial coupling"):
  with members:
    - "spatially coupled mackay neal codes and hsu anastasopoulos codes"
    - "threshold saturation via spatial coupling why convolutional ldpc ensembles perform so well over the bec"
    - "coupled graphical models and their thresholds"
    - "improvement of bp based cdma multiuser detection by spatial coupling"

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)