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 exact ber of bit wise demodulators for one dimensional constellations"
  Abstract: The optimal bit-wise demodulator for M-ary pulse amplitude modulation (PAM) over the additive white Gaussian noise channel is analyzed in terms of uncoded bit-error rate (BER). The BER analysis is based on studying the bit patterns that form a labeling. New closed-form BER expressions for 4-PAM with any labeling are developed. Moreover, closed-form BER expressions for 11 out of 23 possible bit patterns for 8-PAM are presented, which enable us to obtain the BER for 8-PAM with some of the most popular labelings, including the binary reflected Gray code and the natural binary code. Numerical results show that, regardless of the labeling, there is no difference between the optimal demodulator and the symbol-wise demodulator for any BER of practical interest (below 0.1).

Connected through hyperedge HE-1 (induced by source paper "asymptotic comparison of ml and map detectors for multidimensional constellations"):
  with members:
    - "high snr asymptotics of mutual information for discrete constellations with applications to bicm"
    - "constellation shaping for bit interleaved ldpc coded apsk"

Connected through hyperedge HE-2 (induced by source paper "replacing the soft fec limit paradigm in the design of optical communication systems"):
  with members:
    - "four dimensional coded modulation with bit wise decoders for future optical communications"
    - "high snr asymptotics of mutual information for discrete constellations with applications to bicm"
    - "improving soft fec performance for higher order modulations via optimized bit channel mappings"
    - "on the information loss of the max log approximation in bicm systems"
    - "probabilistic signal shaping for bit metric decoding"
    - "achievable rates for four dimensional coded modulation with a bit wise receiver"
    - "spatially coupled ensembles universally achieve capacity under belief propagation"
    - "optimal alphabets and binary labelings for bicm at low snr"

Connected through hyperedge HE-3 (induced by source paper "high snr asymptotics of mutual information for discrete constellations with applications to bicm"):
  with members:
    - "signal shaping for bicm at low snr"
    - "general ber expression for one dimensional constellations"
    - "multiple antenna fading coherent channels with arbitrary inputs characterization and optimization of the reliable information transmission rate"
    - "precoding for outage probability minimization on block fading channels"
    - "optimal alphabets and binary labelings for bicm at low snr"
    - "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)