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: "approximate mimo iterative processing with adjustable complexity requirements"
  Abstract: Targeting only the best achievable bit error rate (BER) performance in iterative receivers operating over multiple-input-multiple-output (MIMO) channels may result in a significant waste of resources, particularly when the achievable BER is considerably better than the target performance [e.g., under good channel conditions and at high signal-to-noise ratio (SNR)]. In contrast to the typical iterative schemes, a practical iterative decoding framework that approximates the soft information exchange is proposed, allowing reduced complexity sphere and channel decoding that is adjustable to the transmission conditions and the required BER. With the proposed approximate soft information exchange, the performance of the exact soft information can still be reached with significant complexity reduction.

Connected through hyperedge HE-1 (induced by source paper "sumis near optimal soft in soft out mimo detection with low and fixed complexity"):
  with members:
    - "scaling up mimo opportunities and challenges with very large arrays"
    - "low complexity detection in large dimension mimo isi channels using graphical models"
    - "efficient soft input soft output tree detection via an improved path metric"
    - "soft input soft output single tree search sphere decoding"

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)